Intranasal Administration of a Polymeric Biodegradable Film to C57BL/6 Mice

Nasal drug delivery in rodents is a challenging procedure, especially for brain targeting, as the position of the material in the nasal cavity determines the success of the administration method. The objective of this study was to assess a novel intranasal administration technique for nose-to-brain delivery of biodegradable nasal films. The method was performed in C57BL/6 (n = 10; age, 8 wk) under inhaled sevoflurane. Twenty-four gauge catheters were used for the procedure. Hydroxypropyl methyl-cellulosebased film was formed in the lumen of the catheter and then delivered into the mouse nostril by pushing it out of the lumen using a trimmed and polished needle. Methylene blue was incorporated in the film-forming gel to indicate the delivery area in which the films were deposited. After administration, all mice recovered from anesthesia without incident. None of the mice showed any signs of injury, discomfort, or nose bleeding, thus allowing us to characterize the administration method as noninvasive. Furthermore, postmortem evaluation revealed olfactory-centered placement of the polymeric films, confirming the accuracy and repeatability of the method. In conclusion, this study documented the use of, a novel, noninvasive, intranasal administration technique for nose-to-brain drug delivery in biodegradable films for use in mice.

Supplementation with uric and ascorbic acid protects stored red blood cells through enhancement of non-enzymatic antioxidant activity and metabolic rewiring

Redox imbalance and oxidative stress have emerged as generative causes of the structural and functional degradation of red blood cells (RBC) that happens during their hypothermic storage at blood banks. The aim of the present study was to examine whether the antioxidant enhancement of stored RBC units following uric (UA) and/or ascorbic acid (AA) supplementation can improve their storability as well as post-transfusion phenotypes and recovery by using in vitro and animal models, respectively. For this purpose, 34 leukoreduced CPD/SAGM RBC units were aseptically split in 4 satellite units each. UA, AA or their mixture were added in the three of them, while the fourth was used as control. Hemolysis as well as redox and metabolic parameters were studied in RBC units throughout storage. The addition of antioxidants maintained the quality parameters of stored RBCs, (e.g., hemolysis, calcium homeostasis) and furthermore, shielded them against oxidative defects by boosting extracellular and intracellular (e.g., reduced glutathione; GSH) antioxidant powers. Higher levels of GSH seemed to be obtained through distinct metabolic rewiring in the modified units: methionine-cysteine metabolism in UA samples and glutamine production in the other two groups. Oxidatively-induced hemolysis, reactive oxygen species accumulation and membrane lipid peroxidation were lower in all modifications compared to controls. Moreover, denatured/oxidized Hb binding to the membrane was minor, especially in the AA and mix treatments during middle storage. The treated RBC were able to cope against pro-oxidant triggers when found in a recipient mimicking environment in vitro, and retain control levels of 24h recovery in mice circulation. The currently presented study provides (a) a detailed picture of the effect of UA/AA administration upon stored RBCs and (b) insight into the differential metabolic rewiring when distinct antioxidant "enhancers" are used.

A Comprehensive Review of the Cardiovascular Protective Properties of Silibinin/Silymarin: A New Kid on the Block

Silibinin/silymarin has been used in herbal medicine for thousands of years and it is well-known for its hepato-protective properties. The present comprehensive literature review aimed to critically summarize the pharmacological properties of silymarin extract and its main ingredient silibinin in relation to classical cardiovascular risk factors (e.g., diabetes mellitus, etc.). We also assessed their potential protective and/or therapeutic application in cardiovascular diseases (CVDs), based on experimental and clinical studies. Pre-clinical studies including in vitro tests or animal models have predominantly implicated the following effects of silymarin and its constituents: (1) antioxidant, (2) hypolipidemic, (3) hypoglycemic, (4) anti-hypertensive and (5) cardioprotective. On the other hand, a direct amelioration of atherosclerosis and endothelial dysfunction after silymarin administration seems weak based on scarce data. In clinical trials, the most important findings are improved (1) glycemic and (2) lipid profiles in patients with type 2 diabetes mellitus and/or hyperlipidemia, while (3) the anti-hypertensive effects of silibinin/silymarin seem very modest. Finally, the changes in clinical endpoints are not robust enough to draw a firm conclusion. There are significant limitations in clinical trial design, including the great variety in doses and cohorts, the underlying conditions, the small sample sizes, the short duration and the absence of pharmacokinetic/pharmacodynamic tests prior to study commitment. More data from well-designed and high-quality pre-clinical and clinical studies are required to firmly establish the clinical efficacy of silibinin/silymarin and its possible therapeutic application in cardiovascular diseases.

Corpuscular Fragility and Metabolic Aspects of Freshly Drawn Beta-Thalassemia Minor RBCs Impact Their Physiology and Performance Post Transfusion: A Triangular Correlation Analysis In Vitro and In Vivo

The clarification of donor variation effects upon red blood cell (RBC) storage lesion and transfusion efficacy may open new ways for donor–recipient matching optimization. We hereby propose a “triangular” strategy for studying the links comprising the transfusion chain—donor, blood product, recipient—as exemplified in two cohorts of control and beta-thalassemia minor (βThal+) donors (n = 18 each). It was unraveled that RBC osmotic fragility and caspase-like proteasomal activity can link both donor cohorts to post-storage states. In the case of heterozygotes, the geometry, size and intrinsic low RBC fragility might be lying behind their higher post-storage resistance to lysis and recovery in mice. Moreover, energy-related molecules (e.g., phosphocreatine) and purine metabolism factors (IMP, hypoxanthine) were specifically linked to lower post-storage hemolysis and phosphatidylserine exposure. The latter was also ameliorated by antioxidants, such as urate. Finally, higher proteasomal conservation across the transfusion chain was observed in heterozygotes compared to control donors. The proposed “triangularity model” can be (a) expanded to additional donor/recipient backgrounds, (b) enriched by big data, especially in the post-transfusion state and (c) fuel targeted experiments in order to discover new quality biomarkers and design more personalized transfusion medicine schemes.

The Post-Storage Performance of RBCs from Beta-Thalassemia Trait Donors Is Related to Their Storability Profile

Blood donors with beta-thalassemia traits (βThal+) have proven to be good "storers", since their stored RBCs are resistant to lysis and resilient against oxidative/proteotoxic stress. To examine the performance of these RBCs post-storage, stored βThal+ and control RBCs were reconstituted in plasma donated from transfusion-dependent beta-thalassemic patients and healthy controls, and incubated for 24 h at body temperature. Several physiological parameters, including hemolysis, were evaluated. Moreover, labeled fresh/stored RBCs from the two groups were transfused in mice to assess 24 h recovery. All hemolysis metrics were better in the group of heterozygotes and distinguished them against controls in the plasma environment. The reconstituted βThal+ samples also presented higher proteasome activity and fewer procoagulant extracellular vesicles. Transfusion to mice demonstrated that βThal+ RBCs present a marginal trend for higher recovery, regardless of the recipient's immune background and the RBC storage age. According to correlation analysis, several of these advantageous post-storage characteristics are related to storage phenotypes, like the cytoskeleton composition, low cellular fragility, and enhanced membrane proteostasis that characterize stored βThal+ RBCs. Overall, it seems that the intrinsic physiology of βThal+ RBCs benefits them in conditions mimicking a recipient environment, and in the circulation of animal models; findings that warrant validation in clinical trials.

Nonalcoholic fatty liver disease: The role of quercetin and its therapeutic implications

Nonalcoholic fatty liver disease (NAFLD) is the most common form of chronic liver disease, affecting almost one-third of the general population and 75% of obese patients with type 2 diabetes. The aim of this article is to review the current evidence concerning the role of quercetin, a natural compound and flavonoid, and its possible therapeutic effects on this modern-day disease. Despite the fact that the exact pathophysiological mechanisms through which quercetin has a hepatoprotective effect on NAFLD are still not fully elucidated, this review clearly demonstrates that this flavonoid has potent antioxidative stress action and inhibitory effects on hepatocyte apoptosis, inflammation, and generation of reactive oxygen species, factors which are linked to the development of the disease. NAFLD is closely associated with increased dietary fat consumption, especially in Western countries. The hepatoprotective effect of quercetin against NAFLD merits serious consideration and further validation by future studies.

Tbx5 navigates through the labyrinth of adult cardiac regeneration

Background

Heart failure is the major cause of death and morbidity in industrialized countries with an estimated 23 million people affected per year, representing 30% of all global deaths. Injury to the adult mammalian cardiac muscle, often leads to a heart attack due to irreversible loss of a large number of cardiomyocytes (CM) and other cardiac interstitial cells, creating an unmet need for identifying a cardiac progenitor cell (CPC) population for cardiac replenishment. In contrast, amphibians and neonatal rodents possess the ability to regenerate their heart upon injury. It has been suggested recently that idle cardiac regenerative mechanisms may be present in adult mammals, inhibited by exogenous cues, or lack of.

Murine and human CPCs can be isolated through the expression of Pdgfra, Kdr, and our novel surface marker, Gfra2. In addition, the expression of the embryonic transcription factor TBX5, is paramount for differentiation towards a cardiomyocyte fate. Therefore, Tbx5-expressing CPCs could be an effective target for proof-of-concept studies in the heart repair field, inclined to pharmacological modulation in patients with ischemic heart disease.

Purpose

To characterise an adult Tbx5-expressing CPC population in the injured heart. Using a developmental approach to two adult heart injury murine models, we show that Tbx5-expressing CPC exist in the injured adult mammalian heart, with a molecular signature that strongly correlates with that of embryonic and neonatal CPCs.

Methods

A well-defined tamoxifen-induced Tbx5-Cre; Rosa26R-eYFP/eYFP transgenic mouse model was employed, where myocardial infarction (MI) was induced through reperfusion/ischemia or chemical injury.

Cardiac cells expressing YFP+ cells were collected from the adult injured hearts five to seven days post-injury. Flow-cytometric and single-cell mRNA-seq analysis was performed in order to collect and compare those YFP+ cells to control adult uninjured cardiac interstitial cells, and early neonatal-derived CPCs.

Results

Immunohistochemical analysis indicated that YFP+ interstitial cells were mostly present in the injury site, but also in distal cardiac areas.

Flow cytometric analysis of live cells pinpoint these YFP+ cells are part of a CPC-like population.

Single-cell mRNA transcriptomic analysis revealed that YFP+ cells resemble early postnatal CPC.

Yet, YFP+ cells never expressed CM markers in vivo, but they did differentiate into CM-like cells, in vitro.

Conclusions

Upon MI, the adult heart possess an interstitial cell population that transiently re-activates the pioneer cardiac embryonic transcription factor Tbx5.

The Tbx5-expressing cell population transcriptomically resembles that of CPC, which could promote CM regeneration upon neonatal injury.

We show that Tbx5 lies in the centre of a novel adult CPC population. The adult heart microenvironment may hinder mammalian CM regeneration through regulation of the Tbx5-induced cardiac gene program.

Funding Acknowledgement

Type of funding sources: Public grant(s) – National budget only. Main funding source(s): Hellenic Foundation for Research & Innovation

Cilostazol Mediates Immune Responses and Affects Angiogenesis During the Acute Phase of Hind Limb Ischemia in a Mouse Model

BACKGROUND

Cilostazol is a drug of choice for the treatment of intermittent claudication that also affects innate and adaptive immune cells. The purpose of our study was the evaluation of cilostazol's impact on the immune and angiogenic response in murine models of hind limb ischemia.

METHODS

We used 108 immunodeficient NOD.CB17-Prkdcscid/J mice and 108 wild-type CB17 mice. At day 0 (D0), all animals underwent hind limb ischemia. Half of them in both groups received daily cilostazol starting at D0 and for the next 7 postoperative days, while the rest of them served as controls, receiving vehicle. Interleukin (IL) 2, IL-4, IL-6, IL-10, IL-17A, tumor necrosis factor α (TNF-α), and interferon γ (IFN-γ) serum concentrations were measured by flow cytometry on postsurgery days D1, D3, D5, and D7. On D7, both groups underwent positron emission tomography scan with ⁶⁸Ga-RGD. Mice were euthanatized and gastrocnemius muscles were obtained for histological evaluation.

RESULTS

There was a statistically significant augmentation (P < .05) in IL-4, IL-10, IL-6, and IFN-γ concentrations in treated CB17 animals, while IL-2 was significantly suppressed. Significant difference was detected between the CiBisch and Bisch groups on D1 and D7 (P < .05) in CD31 staining. In treated NOD.CB17 animals, TNF-α, IL-6, and IFN-γ presented significant augmentation, while ⁶⁸Ga-NODAGA-RGDfK uptake and CD31 expression were found significantly lower for both legs in comparison to the control.

CONCLUSION

Cilostazol seems to significantly increase angiogenesis in wild-type animals during the first postoperational week. It also influences immune cells, altering the type of immune response by promoting anti-inflammatory cytokine production in wild-type animals, while it helps toward inflammation regression in immunodeficient animals.

The neuroprotective agent Rasagiline mesylate attenuates cardiac remodeling after experimental myocardial infarction

AIM

Rasagiline mesylate (N-propargyl-1 (R)-aminoindan) (RG) is a selective, potent irreversible inhibitor of monoamine oxidase-B with cardioprotective and anti-apoptotic properties. We investigated whether it could be cardioprotective in a rat model undergoing experimental myocardial infarction (MI) by permanent ligation of the left anterior descending coronary artery.

METHODS AND RESULTS

RG was administered, intraperitoneally, for 28 days (2 mg/kg) starting 24 h after MI induction. Echocardiography analysis revealed a significant reduction in left ventricular end-systolic and diastolic dimensions and preserved fractional shortening in RG-treated compared with normal saline group at 28 days post-MI (31.6 ± 2.3 vs. 19.6 ± 1.8, P < 0.0001), respectively. Treatment with RG prevented tissue fibrosis as indicated by interstitial collagen estimation by immunofluorescence staining and hydroxyproline content and attenuated the number of apoptotic myocytes in the border zone (65%) as indicated by terminal deoxynucleotidyl transferase dUTP nick end labeling (TUNEL) assay. Caspase 3 relative protein levels were significantly decreased in the non-infarcted myocardium. Markedly decreased malondialdehyde levels in the border zone indicate a reduction in tissue oxidative stress.

CONCLUSIONS

Our study demonstrates a positive effect of RG in the post-MI period with a significant attenuation in cardiac remodelling.

Effect of ovariectomy and Sideritis euboea extract administration on large artery mechanics, morphology, and structure in middle-aged rats

BACKGROUND

Arterial function is regulated by estrogen, but no consistent pattern of arterial mechanical remodeling in response to depleted estrogen levels is available.

OBJECTIVE

To examine long-term effects of ovariectomy (OVX) on the mechanical properties, morphology, and histological structure of the carotid artery in middle-aged rats and a potentially protective effect of Sideritis euboea extract (SID), commonly consumed as "mountain tea".

METHODS

10-month-old female Wistar rats were allocated into control (sham-operated), OVX, OVX+SID, and OVX+MALT (maltodextrin; excipient used for dilution of SID) groups. They were sacrificed after 6 months and their carotid arteries were submitted to inflation/extension tests and to dimensional and histological evaluation.

RESULTS

Remodeling in OVX rats was characterized by a decreased in situ axial extension ratio, along with increased opening angle, thickness, and area of the vessel wall and of its medial layer, but unchanged lumen diameter. Compositional changes involved increased elastin/collagen densities. Characterization by the "four-fiber" microstructure-motivated model revealed similar in situ biaxial response of carotid arteries in OVX and control rats.

CONCLUSIONS

Carotid artery remodeling in OVX rats was largely consistent with hypertensive remodeling, despite the minor arterial pressure changes found, and was not altered by administration of SID, despite previous evidence of its osteo-protective effect.

18-Fluoro-2-deoxy-D-glucose positron emission tomography/computed tomography scan for monitoring the therapeutic response in experimental Staphylococcus aureus foreign-body osteomyelitis

Background

18-Fluoro-2-deoxy-d-glucose positron emission tomography combined with computed tomography (¹⁸F-FDG PET/CT) scan is useful for diagnosis of osteoarticular infections. Whether ¹⁸F-FDG PET/CT scanning may be used for therapeutic monitoring is not clear. The objective of this study was to develop ¹⁸F-FDG PET/CT scanning for monitoring therapeutic response to antimicrobials in experimental Staphylococcus aureus osteomyelitis.

Methods

A total of 22 rabbits were studied. In 20 animals, the right tibia was inoculated intraoperatively with S. aureus. Two control animals were inoculated with normal saline. A needle was placed in the tibia as a foreign body. Infection was allowed to develop for 21 days when ¹⁸F-FDG PET/CT was performed, the needle was removed, and bone specimens were cultured to confirm infection. Antimicrobial therapy with daptomycin was initiated in all successfully infected animals for 1, 3, or 6 weeks. Following completion of treatment, a second ¹⁸F-FDG PET/CT was performed, animals were euthanized, and infected tibias were harvested for quantitative cultures and histology. A positive scan was defined as ¹⁸F-FDG signal activity greater in the infected tibia than that of the contralateral non-infected control tibia. Therapeutic response was measured by the change of ¹⁸F-FDG signal activity in the infected tibia.

Results

All successfully infected animals (n = 14), with microbiologically and/or histologically confirmed osteomyelitis, had positive ¹⁸F-FDG PET/CT scans, while the two control animals had negative scans despite the presence of the foreign body [mean maximum standardized uptake value (SUVmax) (±SD) values 2.96 (±0.80) vs. 1 (±1.10), respectively, P = 0.04]. In the 14 successfully infected animals, the mean SUVmax was significantly higher in the infected compared to the uninfected tibia (P < 0.0001). A SUVmax of 1.4, when used as a cutoff for infection, yielded a diagnostic accuracy of 93 %. At the end of treatment, successfully treated animals and saline controls had a negative ¹⁸F-FDG PET/CT scan (n = 4), while animals with persistent infection despite treatment (n = 12) had a positive ¹⁸F-FDG PET/CT scan (SUVmax 1.0–3.0) (p < 0.001). SUVmax values were significantly reduced after 42 days of treatment from 3.15 ± 0.5 (day 7) to 1.71 ± 0.37 (day 42) (p = 0.05).

Conclusions

¹⁸F-FDG PET/CT scan is a sensitive and specific tool in therapeutic monitoring of experimental foreign-body osteomyelitis.

Maternal weight as an alternative determinant of the gestational day of Wistar rats housed in individually-ventilated cages

One of the commonly used animal models in fertility, developmental and neurobiological studies is the laboratory rat. The early recognition of rat pregnancy and confirmation of the exact embryonic day are vital. The aim of this study was to investigate the correlation of maternal weight at the time of conception to its increase throughout gestation, aiming to develop a mathematical model, which can be used for the determination of the exact day of pregnancy, set the threshold, and monitor pregnancy from the onset. We studied a total of 173 Wistar rats with a mean body weight of 238.22 ± 34.9 g. After 72 h at the male’s cages, we considered as Day 0 (D0) the day in which a copulatory plug or sperm was found during the vaginal smear examination. After that period the female animals were transferred into their cages, and weight monitoring started 14 days (D14) after D0, until parturition. Based on the statistical analysis, there is a correlation between maternal body weight at D0 and maternal body weight from D14 to D19. Moreover, the average weight gain from D14 to D19 is positively correlated to initial female body weight, while there is no correlation between each pregnant animal’s weight from D14 to D19 and litter size. A mathematical model was developed as a tool for the verification of the day of pregnancy. In conclusion, continuous monitoring of maternal weight after D14 can be a reliable method for the recognition of pregnancy and determination of the exact gestational day.

A comparative anatomic and physiologic overview of the porcine heart

Despite advances during the last 2 decades in every aspect of cardiovascular research (interventional cardiology, cardiopulmonary resuscitation, and so forth), Western societies still are plagued by the consequences of cardiovascular disease. Consequently the discovery of new regimens and therapeutic interventions is of utmost importance. Research using human subjects is associated with substantial methodologic and ethical considerations, and the quest for an appropriate animal model for the human cardiovascular system has led to swine. The porcine heart bears a close resemblance to the human heart in terms of its coronary circulation and hemodynamic similarities and offers ease of implementation of methods and devices from human healthcare facilities. A thorough comprehension of the anatomy and physiology of the porcine cardiovascular system should focus on differences between swine and humans as well as similarities. Understanding these differences and similarities is essential to extrapolating data appropriately and to addressing the social demand for the ethical use of animals in biomedical research.

Transarterial embolization with sorafenib in animal livers: a pharmacokinetics study

PURPOSE

To assess the safety and feasibility of the targeted delivery of the antiangiogenic drug sorafenib to the liver using transarterial chemoembolization methodology as a novel approach to hepatocellular carcinoma (HCC) therapy.

MATERIALS AND METHODS

Seven healthy New Zealand white rabbits were used in the study. After placement of a catheter in the common hepatic artery, six rabbits were treated with chemoembolization of sorafenib in iodized oil (Lipiodol) (sorafenib dose 0.1 mg/kg), and one rabbit received Lipiodol only. Liquid chromatography tandem mass spectrometry was used to measure the concentration of sorafenib in the peripheral blood and liver tissue 24 hours and 72 hours after treatment. Histochemical staining of the liver sections and biochemical measurements were performed.

RESULTS

The administration of sorafenib in Lipiodol emulsions by transarterial chemoembolization resulted in sorafenib concentrations of 794 ng/g ± 240 and 64 ng/g ± 15 in the liver tissue 24 hours and 72 hours after treatment. The average liver-to-serum ratios 24 hours and 72 hours after treatment were approximately 14 and 22. The histochemical staining of the liver tissue sections and aspartate aminotransferase, alanine aminotransferase, γ-glutamyltransferase and total bilirubin concentrations indicated no significant liver damage.

CONCLUSIONS

Transarterial chemoembolization with sorafenib in Lipiodol is an effective methodology for the localized delivery of this drug to the liver and has possible practical implications in therapeutic interventions for the treatment of hepatocellular carcinoma.

The influence of the location of a nest box in an individually ventilated cage on the preference of mice to use it

The improvement of housing conditions for mice by using environmental enrichment materials is of high concern for the scientific community. Plastic, autoclavable nest boxes are commercially available and ready to use for specific cases such as in individually ventilated cages, metabolic cages, or during toxicological studies. The aim of this study was to see if the location of the nest box within the cage could influence the mice to prefer and use it. Located on the cage floor or hung from the cage lid, a nest box (MPLEX, Otto Environmental, Milwaukee, Wisconsin), enriched the cages. The study concluded that the location of the nest boxes in the individually ventilated cage plays a significant role in the mice preferring to use it or to avoid it. It is also important to use environmental enrichment items that provide animals with the possibility of expressing their preferences and manipulating them in a way to cope better with their environmental conditions.