Publications by authors named "Avtar Meena"

Optically active ultrabright imaging agents are shown to delineate tumor location with deep tissue visualization in pre noclinical tumor models. NanoGhosts (NGs) particles are reconstructed from the cell membrane and integrated with organic fluorophores to attain ultra-brightness for solid tumor imaging. Moreover, the integration of amphiphilic and lipophilic molecules reveals structural characteristics of NGs (≈70 nm), which also alter their brightness.

View Article and Find Full Text PDF

Recent discoveries have established the pivotal role of IL-9-secreting immune cells in a wide spectrum of inflammatory and autoimmune diseases. However, little is known about how IL-9 contributes to the etiology of inflammatory bone loss in PMO. We observed that IL-9 has a pathological impact on inflammatory bone loss in ovariectomized (Ovx) mice.

View Article and Find Full Text PDF

Lipid nanoparticles have been recognized as a powerful weapon for delivering various imaging and therapeutic agents to the localized solid tumors, especially brain tumors individually or in combination. Promisingly, lipid-based nanosystems have been considered as safe delivery systems which are even approved by the Food and Drug Administration (FDA) and the European Medicines Agency (EMA). One recent spotlight of lipid nanoparticles as COVID-19 mRNA vaccines where lipid nanoparticles play an important role in effectively protecting and delivering mRNA to the desired cells.

View Article and Find Full Text PDF

Cancer diagnoses have been increasing worldwide, and solid tumors are among the leading contributors to patient mortality, creating an enormous burden on the global healthcare system. Cancer is responsible for around 10.3 million deaths worldwide.

View Article and Find Full Text PDF

Introduction: The mechanism underlying radiation-induced gut microbiota dysbiosis is undefined. This study examined the effect of radiation on the intestinal Paneth cell α-defensin expression and its impact on microbiota composition and mucosal tissue injury and evaluated the radio-mitigative effect of human α-defensin 5 (HD5).

Methods: Adult mice were subjected to total body irradiation, and Paneth cell α-defensin expression was evaluated by measuring α-defensin mRNA by RT-PCR and α-defensin peptide levels by mass spectrometry.

View Article and Find Full Text PDF

Introduction: Chronic stress is co-morbid with alcohol use disorder that feedback on one another, thus impeding recovery from both disorders. Stress and the stress hormone corticosterone aggravate alcohol-induced intestinal permeability and liver damage. However, the mechanisms involved in compounding tissue injury by stress/corticosterone and alcohol are poorly defined.

View Article and Find Full Text PDF

Significance: Light is a good probe for studying the nanoscale-level structural or molecular-specific structural properties of brain cells/tissue due to stress, alcohol, or any other abnormalities. Chronic alcoholism during pregnancy, i.e.

View Article and Find Full Text PDF

Intestinal epithelial tight junction disruption is a primary contributing factor in alcohol-associated endotoxemia, systemic inflammation, and multiple organ damage. Ethanol and acetaldehyde disrupt tight junctions by elevating intracellular Ca. Here we identify TRPV6, a Ca-permeable channel, as responsible for alcohol-induced elevation of intracellular Ca, intestinal barrier dysfunction, and systemic inflammation.

View Article and Find Full Text PDF

Iron is a crucial element required for the proper functioning of the body. For instance, hemoglobin is the vital component in the blood that delivers oxygen to various parts of the body. The heme protein present in hemoglobin comprises iron in the form of a ferrous state which regulates oxygen delivery.

View Article and Find Full Text PDF

Corticosterone, the stress hormone, exacerbates alcohol-associated tissue injury, but the mechanism involved is unknown. We examined the role of the glucocorticoid receptor (GR) in corticosterone-mediated potentiation of alcohol-induced gut barrier dysfunction and systemic response. Hepatocyte-specific GR-deficient (GR ) and intestinal epithelial-specific GR-deficient (GR ) mice were fed ethanol, combined with corticosterone treatment.

View Article and Find Full Text PDF

The spectrum of health complications instigated by coronavirus disease 2019 (COVID-19, caused by the novel severe acute respiratory syndrome coronavirus 2 or SARS-CoV-2) pandemic has been diverse and complex. Besides the evident pulmonary and cardiovascular threats, accumulating clinical data points to several neurological complications, which are more common in elderly COVID-19 patients. Recent pieces of evidence have marked events of neuro infection and neuroinvasion, producing several neurological complications in COVID-19 patients; however, a systematic understanding of neuro-pathophysiology and manifested neurological complications, more specifically in elderly COVID-19 patients is largely elusive.

View Article and Find Full Text PDF

Alcohol use disorders are associated with altered stress responses, but the impact of stress or stress hormones on alcohol-associated tissue injury remain unknown. We evaluated the effects of chronic restraint stress on alcohol-induced gut barrier dysfunction and liver damage in mice. To determine whether corticosterone is the stress hormone associated with the stress-induced effects, we evaluated the effect of chronic corticosterone treatment on alcoholic tissue injury at the Gut-Liver-Brain (GLB) axis.

View Article and Find Full Text PDF

Neuroinflammation is implicated in the pathogenesis of alcohol use disorders. We investigated the role of Gut-Brain interactions in alcohol-induced neuroinflammation by probiotic-mediated manipulation of intestinal dysbiosis in mice. Chronic ethanol feeding induced dysbiosis, as evidenced by an increase in Firmicutes/Bacteroidetes ratio and depletion of species in the colon.

View Article and Find Full Text PDF

The tight junction (TJ) and barrier function of colonic epithelium is highly sensitive to ionizing radiation. We evaluated the effect of lysophosphatidic acid (LPA) and its analog, Radioprotein-1, on γ-radiation-induced colonic epithelial barrier dysfunction using Caco-2 and m-IC cell monolayers in vitro and mice in vivo. Mice were subjected to either total body irradiation (TBI) or partial body irradiation (PBI-BM5).

View Article and Find Full Text PDF

The rapidly evolving coronavirus disease 2019 (COVID-19, caused by severe acute respiratory syndrome coronavirus 2- SARS-CoV-2), has greatly burdened the global healthcare system and led it into crisis in several countries. Lack of targeted therapeutics led to the idea of repurposing broad-spectrum drugs for viral intervention. In vitro analyses of hydroxychloroquine (HCQ)'s anecdotal benefits prompted its widespread clinical repurposing globally.

View Article and Find Full Text PDF

On January 26, 2018, the 23rd annual Alcohol and Immunology Research Interest Group (AIRIG) meeting was held at the University of Colorado Denver, Anschutz Medical Campus, Aurora, Colorado. The meeting consisted of plenary sessions with oral presentations and a poster presentation session. There were four plenary sessions that covered a wide range of topics relating to alcohol use: Alcohol and Liver Disease; Alcohol, Inflammation and Immune Response; Alcohol and Organ Injury; Heath Consequences and Alcohol Drinking.

View Article and Find Full Text PDF

Recent study indicated that glutamine prevents alcoholic tissue injury in mouse gut and liver. Here we investigated the potential role of Epidermal Growth Factor Receptor (EGFR) in glutamine-mediated prevention of ethanol-induced colonic barrier dysfunction, endotoxemia and liver damage. Wild-type and EGFR*Tg transgenic (expressing dominant negative EGFR) mice were fed 1-6% ethanol in Lieber-DeCarli diet.

View Article and Find Full Text PDF

Alcohol consumption has been shown to cause dysbiosis, but the mechanism involved in it is unknown. Recurrent colitis is known to induce expression of α-defensins in the colon, but the effect of alcohol consumption on it is not known. We investigated the effect of ethanol on α-defensin expression in the small intestine and colitis-induced expression in colon in mice.

View Article and Find Full Text PDF

Fetal alcohol spectrum disorders (FASD) are associated with social interaction behavior and gastrointestinal (GI) abnormalities. These abnormal behaviors and GI abnormalities overlap with autism spectrum disorder (ASD). We investigated the effect of fetal alcohol exposure (FAE) on social interaction deficits (hallmark of autism) in mice.

View Article and Find Full Text PDF

A critical barrier in treating diarrheal disease is easy-to-use effective treatments. Rx100 is a first in class, novel small molecule that has shown efficacy after both subcutaneous and oral administration in a mouse cholera-toxin- and Citrobacter rodentium infection-induced diarrhea models. Our findings indicate that Rx100 a metabolically stable analog of the lipid mediator lysophosphatidic acid blocks activation of CFTR-mediated secretion responsible for fluid discharge in secretory diarrhea.

View Article and Find Full Text PDF

Pathogenesis of alcohol-related diseases such as alcoholic hepatitis involves gut barrier dysfunction, endotoxemia, and toxin-mediated cellular injury. Here we show that Lactobacillus plantarum not only blocks but also mitigates ethanol (EtOH)-induced gut and liver damage in mice. L.

View Article and Find Full Text PDF

The apical junctional complex (AJC), which includes tight junctions (TJs) and adherens junctions (AJs), determines the epithelial polarity, cell-cell adhesion and permeability barrier. An intriguing characteristic of a TJ is the dynamic nature of its multiprotein complex. Occludin is the most mobile TJ protein, but its significance in TJ dynamics is poorly understood.

View Article and Find Full Text PDF

The role of reactive oxygen species (ROS) in osmotic stress, dextran sulfate sodium (DSS) and cyclic stretch-induced tight junction (TJ) disruption was investigated in Caco-2 cell monolayers and restraint stress-induced barrier dysfunction in mouse colon Live cell imaging showed that osmotic stress, cyclic stretch and DSS triggered rapid production of ROS in Caco-2 cell monolayers, which was blocked by depletion of intracellular Ca by 1,2-bis-(-aminophenoxy)ethane-,,','-tetraacetic acid. Knockdown of Ca1.3 or TRPV6 channels blocked osmotic stress and DSS-induced ROS production and attenuated TJ disruption and barrier dysfunction.

View Article and Find Full Text PDF

Ethanol is metabolized into acetaldehyde in most tissues. In this study, we investigated the synergistic effect of ethanol and acetaldehyde on the tight junction integrity in Caco-2 cell monolayers. Expression of alcohol dehydrogenase sensitized Caco-2 cells to ethanol-induced tight junction disruption and barrier dysfunction, whereas aldehyde dehydrogenase attenuated acetaldehyde-induced tight junction disruption.

View Article and Find Full Text PDF

Background: Alcohol consumption is one of the major risk factors for colorectal cancer. However, the mechanism involved in this effect of alcohol is unknown.

Methods: We evaluated the effect of chronic ethanol feeding on azoxymethane and dextran sulfate sodium (AOM/DSS)-induced carcinogenesis in mouse colon.

View Article and Find Full Text PDF