Associations of Vitamin D Receptor Polymorphism rs1544410 with Adiposity Phenotypes

Background: Vitamin D receptor (VDR) is present on adipocytes, and many studies were performed to investigate the association between polymorphisms in VDR gene with obesity. However, in the Arab Gulf populations, whereas obesity prevalence is increasing dramatically, only a few studies were addressed this relation with obesity based only on body mass index. This study aimed to find the association between three different VDR polymorphisms BsmI (rs1544410), ApaI (rs7975232) and TaqI (rs731236) BsmI, with the adiposity phenotypes (BMI, body fat BF% and waist circumference (WC) as a marker of visceral obesity. Method: In this study, 142 young female subjects from Qatar University were recruited. The study subjects were classified into 88 control subjects (BMI <24.9 kg/m2) with a mean age of 21.65 years and 54 overweight/obese subjects (BMI ≥25 kg/m2) with a mean age of 22.79 years. Blood samples and anthropometric measurements were evaluated. TaqMan assay was used to examine the genotyping of the three SNPs BsmI, ApaI, and TaqI using RT-PCR. In addition, vitamin D and insulin levels were measured using ELISA kits. The adiposity phenotypes were evaluated by anthropometric measurements of body weight, height, waist circumference and BF% were assessed by Body composition analyzer. Results: The results showed that 80.3% of the study subjects were vitamin D insufficient/deficient. The main finding of the current study revealed that the carrier for the minor allele (A) in the BsmI of VDR have significantly higher BMI, WC and BF% values with p-values of 0.009, 0.015 and 0.04, respectively. In addition, it was found that increased WC is associated with lower (suboptimal) vitamin D level with an odds ratio of 3.12 and 95% CI of (1.01-9.63) with a p-value of 0.048. Conclusion: The adiposity phenotype indicators including BMI, WC, and BF% were significantly associated with the minor allele (A) for BsmI (rs1544410); suggesting the possible relation of VDR polymorphism with obesity in Qatar. Vitamin D deficiency could affect the BF% in overweight and obese subjects.Qatar university grant #supported this study QUST-CAS-FALL-15/16-23

Experimental and Biological Investigation of Hemodynamics-induced Injuries for Cardiovascular Disorders

Introduction:Abdominal aortic aneurysm (AAA) is a degenerative disease process of the abdominal aorta that leads to a focal dilation and irreversible remodeling of the arterial wall. In this condition, the aortic vessel diameter is dilated beyond 50% its its size.AAA might gradually expand until rupture If left untreated. Current surgical treatment options also are associated with high mortality rates. Therefore, for AAA, it is critically important to determine when the risk of rupture justifies repair. Current clinical practice is to surgically repair large AAAs with diameter > 5.5 cm. However, the incidence of rupture is independent of the diameter size. Currently there is no accepted technique to quantify the risk of rupture for individual AAAs. It is believed that, rupture locations are where peak wall stresses act. Hemodynamic forces by the flowing blood such as shear stress are also thought to contribute to the formation of aneurysm leading to rupture. Endothelial cells respond to disturbed flows in the aneurysm and initiate inflammation that are thought to be important in disease progression. However, little is known about the flow dynamics in AAA, and how it affects endothelial cell biology leading to AAA rupture. Methods: In this project, we will use different flow systems to induce shear stress over cell's monolayer. After inducing shear stress, gene expression for shear responsive genes and inflammatory markers will be assessed. Basically, we used the peristaltic pump to induce pulsatile flow over cell's monolayer, and laminar flow using our modified set up. We will compare gene expression data obtained from those two systems with data obtained from our Fluigent pressurized driven pump. Then, we will use another state-of-the-art system, namely a biological pulsed duplicator. Using the system, endothelial cells that are cultured within AAA shaped chambers will be exposed to physiological flows in order to reveal differential endothelial cell signals at potential rupture locations Results: In this project, pulsatile and steady flow were successfully induced and validated. Endothelial cells are mostly affected by mechanical signals, mostly shear stress. The cell's cytoskeleton is responsible for cell shape and integrity. Those proteins are affected by fluid flow. We expect to have a differences in the gene expression of different flow conditions. After we obtain the gene expression data, those will be compared to more precise flow set up ( Fluigent pressurized driven pump

Nitric Oxide Releasing Hydrogel Nanoparticles Decreases Epithelial Cell Injuries Associated With Airway Reopening

Introduction: Acute respiratory distress syndrome (ARDS) is an acute inflammatory lung condition. It is characterized by disruption of gas exchange inside the alveoli, accumulation of protein edema, and an increase in lung stiffness. One major cause of ARDS is a lung infection, such as SARS-COV-2 infection. Lungs of ARDS patients need to be mechanically ventilated for airway reopening. Consequently, ventilation might damage delicate lung tissue leading to excess edema, known as ventilator-induced lung injury (VILI). Mortality of COVID-19 patients under VILI seems to be higher than non-COVID patients, necessitating effective preventative therapies. VILI occurs when small air bubbles form in the alveoli, injuring epithelial cells (EPC) due to shear stress. Nitric oxide (NO) inhalation was suggested as a therapy for ARDS, however, it was shown that it is not effective because of the extremely short half-life of NO. Methods:In this study, NO-releasing nanoparticles were produced and tested in an in vitro model, representing airways in the deep lung. Cellular injuries were quantified via fluorescent live/dead assay. Atomic force microscopy (AFM) was used to assess cell morphology. qRT-PCR was performed to assess the expression of inflammatory markers, specifically IL6 and CCL2. ELISA was performed to assess IL6 and confirm qRT-PCR results at the protein level. Finally, ROS levels were assessed in all groups. Results: Here, we show that NO delivery via nanoparticles enhanced EPC survival and recovery, AFM measurements revealed that NO exposure affect cell morphology, while qRT-PCR demonstrated a significant downregulation in IL6 and CCL2 expression when treating the cells to NO both before and after shear exposure. ELISA results for IL6 confirmed qRT-PCR data. ROS experiment results support our findings from previous experiments. Conclusion : These findings demonstrate that NO-releasing nanoparticles can be used as an effective delivery approach of NO to deep lung to prevent/reduce ARDS associated inflammation and cell injuries. This information is particularly useful to treat severe ARDS due to COVID-19 infection. These nanoparticles will be useful when clinically administrated to COVID-19 patients to reduce the symptoms originating from lung distress

Effect of flow-induced shear stress in nanomaterial uptake by cells: Focus on targeted anti-cancer therapy

© 2020 by the authors. Licensee MDPI, Basel, Switzerland. Recently, nanomedicines have gained a great deal of attention in diverse biomedical applications, including anti-cancer therapy. Being different from normal tissue, the biophysical microenvironment of tumor cells and cancer cell mechanics should be considered for the development of nanostructures as anti-cancer agents. Throughout the last decades, many efforts devoted to investigating the distinct cancer environment and understanding the interactions between tumor cells and have been applied bio-nanomaterials. This review highlights the microenvironment of cancer cells and how it is different from that of healthy tissue. We gave special emphasis to the physiological shear stresses existing in the cancerous surroundings, since these stresses have a profound effect on cancer cell/nanoparticle interaction. Finally, this study reviews relevant examples of investigations aimed at clarifying the cellular nanoparticle uptake behavior under both static and dynamic conditions

Do changes in ace-2 expression affect sars-cov-2 virulence and related complications: A closer look into membrane-bound and soluble forms

The SARS-CoV-2 virus utilizes angiotensin converting enzyme (ACE-2) for cell entry and infection. This enzyme has important functions in the renin-angiotensin aldosterone system to preserve cardiovascular function. In addition to the heart, it is expressed in many tissues including the lung, intestines, brain, and kidney, however, its functions in these organs are mostly unknown. ACE-2 has membrane-bound and soluble forms. Its expression levels are altered in disease states and by a variety of medications. Currently, it is not clear how altered ACE-2 levels influence ACE-2 virulence and relevant complications. In addition, membrane-bound and soluble forms are thought to have different effects. Most work on this topic in the literature is on the SARS-CoV virus that has a high genetic resemblance to SARS-Co-V-2 and also uses ACE-2 enzyme to enter the cell, but with much lower affinity. More recent studies on SARS-CoV-2 are mainly clinical studies aiming at relating the effect of medications that are thought to influence ACE-2 levels, with COVID-19 outcomes for patients under these medications. This review paper aims to summarize what is known about the relationship between ACE-2 levels and SARS-CoV/SARS-CoV-2 virulence under altered ACE-2 expression states.The publication of this article was covered with a generous support from BARZAN HOLDING

Using Zebrafish for Investigating the Molecular Mechanisms of Drug-Induced Cardiotoxicity

Over the last decade, the zebrafish (Danio rerio) has emerged as amodel organismfor cardiovascular research.Zebrafish have several advantages over mammalian models. For instance, the experimental cost of using zebrafish is comparatively low; the embryos are transparent, develop externally, and have high fecundity making them suitable for large-scale genetic screening. More recently, zebrafish embryos have been used for the screening of a variety of toxic agents, particularly for cardiotoxicity testing. Zebrafish has been shown to exhibit physiological responses that are similar to mammals after exposure to medicinal drugs including xenobiotics, hormones, cancer drugs, and also environmental pollutants, including pesticides and heavy metals. In this review, we provided a summary for recent studies that have used zebrafish to investigate themolecularmechanisms of drug-induced cardiotoxicity. More specifically, we focused on the techniques that were exploited by us and others for cardiovascular toxicity assessment and described several microscopic imaging and analysis protocols that are being used for the estimation of a variety of cardiac hemodynamic parameters.Huseyin C. Yalcin is supported by Qatar National Research Fund (QNRF), National Priority Research Program NPRP 10-0123-170222,and Qatar University internal funds,QUUGBRC-2017-3 and QUST-BRC-SPR\2017-1. The publication of this article was partially funded by the Qatar National Library

Application of a flow-induced stress wave and investigation of associated injuries on cell monolayers using a parallel plate flow chamber

© 2020 by the authors. Licensee MDPI, Basel, Switzerland. Parallel plate flow chambers are widely used to expose cultured cells to physiological flows for the investigation of a variety of diseases. These applications usually involve the generation of continuous and steady fluid flow over cell monolayers for extended durations, usually a few days. Another technique is to generate a fast high-stress wave over the cells to see the immediate effect of flow-induced stresses. This can be achieved by propagating an air/liquid interface, in other words, a bubble, over cell monolayers. The approach is relevant to the reopening event of fluid-filled lung bronchioles and alveoli during mechanical ventilation therapy of Acute Respiratory Distress Syndrome. This article explains how we generate a stress wave using a parallel plate flow chamber and presents representative results of this wave on cultured lung epithelial cells

Application of a Flow-Induced Stress Wave and Investigation of Associated Injuries on Cell Monolayers Using a Parallel Plate Flow Chamber

Parallel plate flow chambers are widely used to expose cultured cells to physiological flows for the investigation of a variety of diseases. These applications usually involve the generation of continuous and steady fluid flow over cell monolayers for extended durations, usually a few days. Another technique is to generate a fast high-stress wave over the cells to see the immediate effect of flow-induced stresses. This can be achieved by propagating an air/liquid interface, in other words, a bubble, over cell monolayers. The approach is relevant to the reopening event of fluid-filled lung bronchioles and alveoli during mechanical ventilation therapy of Acute Respiratory Distress Syndrome. This article explains how we generate a stress wave using a parallel plate flow chamber and presents representative results of this wave on cultured lung epithelial cells

THE INFLUENCE OF SHEAR STRESS ON NANOMATERIAL'S UPTAKE BY CANCER

Recently, nanotechnology products have been used for a variety of applications including the medical field. Two dimensional (2D) nanomaterials have attracted a growing interest due to its unique properties and ultrathin structure. One common example is MXene, which can be used for cancer photothermal therapy. In this study, two 2D nanomaterials, MXene and MXene/Au nanocomposite were fabricated as photothermal agents. To mimic physiological tumor microenvironment, nanocomposites were tested on MDA-231 breast cancer cells under fluid shear stress (~ 0.1 Dyn/cm2) using a perfusion setup. The uptake of these nanomaterials was tested under fluid flow compared to static culture. The uptake was assessed using confocal microscopy, scanning electron microscopy (EDS) and transmission electron microscopy. Furthermore, viability assessment was performed after exposing the treated cells to laser at different power densities and durations by live/dead assay. This study revealed that there is no difference in cellular uptake under fluid flow compared to static culture. Although MXene alone could increase the temperature up to 100 ° C, its cellular uptake is very low (~ 3 ug/ml) which can only increase the temperature up to 44 ° C which is not sufficient to induce protein denaturation and cellular damage

The influence of shear stress on nanomaterial's uptake by MDA-231 breast cancer cells

Introduction: Recently, nanotechnology products have been used for a variety of applications including the medical field. Two dimensional (2D) nanomaterials have attracted a growing interest due to its unique properties and ultrathin structure. One common example is MXene, which can be used for cancer photothermal therapy. Methodology: In this study, two 2D nanomaterials, MXene and MXene/Au nanocomposite were fabricated as photothermal agents. To mimic physiological tumor microenvironment, nanocomposites were tested on MDA-231 breast cancer cells under fluid shear stress (~ 0.1 Dyn/cm2) using a perfusion setup. The uptake of these nanomaterials was tested under fluid flow compared to static culture, to assess influence of shear stress in material uptake. The uptake was assessed using confocal microscopy, scanning electron microscopy (EDS) and transmission electron microscopy. Furthermore, viability assessment was performed after exposing the treated cells to laser at different power densities and durations by live/dead assay. Results: This study revealed that there is insignificant difference in cellular uptake under fluid flow compared to static culture. Although when exposed to PTT laser irradiation, MXene alone could increase the temperature up to 100 i C, its cellular uptake is very low (~ 3 ug/ml) which could only increase the temperature up to 44 i C which was not sufficient to induce protein denaturation and cellular damage. Conclusion: MXene can be a good candidate for PTT for cancer treatment, but its cellular internalization should be enhanced. This can be achieved by coating the MXene surface and labeling the material with certain ligands that is cancer cell specific