A high throughput live transparent animal bioassay to identify non-toxic small molecules or genes that regulate vertebrate fat metabolism for obesity drug development

<p>Abstract</p> <p>Background</p> <p>The alarming rise in the obesity epidemic and growing concern for the pathologic consequences of the metabolic syndrome warrant great need for development of obesity-related pharmacotherapeutics. The search for such therapeutics is severely limited by the slow throughput of animal models of obesity. Amenable to placement into a 96 well plate, zebrafish larvae have emerged as one of the highest throughput vertebrate model organisms for performing small molecule screens. A method for visually identifying non-toxic molecular effectors of fat metabolism using a live transparent vertebrate was developed. Given that increased levels of nicotinamide adenine dinucleotide (NAD) via deletion of CD38 have been shown to prevent high fat diet induced obesity in mice in a SIRT-1 dependent fashion we explored the possibility of directly applying NAD to zebrafish.</p> <p>Methods</p> <p>Zebrafish larvae were incubated with daily refreshing of nile red containing media starting from a developmental stage of equivalent fat content among siblings (3 days post-fertilization, dpf) and continuing with daily refreshing until 7 dpf.</p> <p>Results</p> <p>PPAR activators, beta-adrenergic agonists, SIRT-1 activators, and nicotinic acid treatment all caused predicted changes in fat, cholesterol, and gene expression consistent with a high degree of evolutionary conservation of fat metabolism signal transduction extending from man to zebrafish larvae. All changes in fat content were visually quantifiable in a relative fashion using live zebrafish larvae nile red fluorescence microscopy. Resveratrol treatment caused the greatest and most consistent loss of fat content. The resveratrol tetramer Vaticanol B caused loss of fat equivalent in potency to resveratrol alone. Significantly, the direct administration of NAD decreased fat content in zebrafish. Results from knockdown of a zebrafish G-PCR ortholog previously determined to decrease fat content in <it>C. elegans </it>support that future GPR142 antagonists may be effective non-toxic anti-obesity therapeutics.</p> <p>Conclusion</p> <p>Owing to the apparently high level of evolutionary conservation of signal transduction pathways regulating lipid metabolism, the zebrafish can be useful for identifying non-toxic small molecules or pharmacological target gene products for developing molecular therapeutics for treating clinical obesity. Our results support the promising potential in applying NAD or resveratrol where the underlying target protein likely involves Sirtuin family member proteins. Furthermore data supports future studies focused on determining whether there is a high concentration window for resveratrol that is effective and non-toxic in high fat obesity murine models.</p

Current status of healthcare-associated enteroviral (non-polio) infections

Here we present the data on foreign research publications describing healthcare-associated enteroviral (nonpolio) infections (HAI) sought in the Worldwide Database for Nosocomial Outbreaks (Institut für Hygiene und Umweltmedizin, Universitȁtmedizincomplex “Charite”, Germany) as well as PubMed search engine (The United States National Library), covering 1936–2017 timeframe. The publications retrieved contained the data on 28 nosocomial outbreaks caused by Enterovirus A (EV-A71), В (Echoviruses 11, 17, 18, 30, 31, 33, Coxsackie viruses А9, В2, В5) and D (EV-D68). It was discovered that the majority of the nosocomial enteroviral (non-polio) outbreaks occurred in obstetric hospitals and neonatal units so that children were mainly maternally infected. In addition, a case associated with intrauterine infection was described. It was shown that outbreaks might be started by an infected child at the incubation period. Single publications reported nosocomial outbreaks in geriatric hospitals. Generally, nosocomial enteroviral (non-polio) outbreaks were characterized by polymorphic clinical picture caused by any certain pathogen serotype and within a single site of the infection. Few lethal outcomes were recorded. Enterovirus B species dominated among identified etiological agents. Violated hospital hygiene and infection control contributing to spread of infection were among those found in neonatal units: putting used diapers out on baby bed prior disposal, sharing bathtub, toys and household objects as well as poor hand hygiene in medical workers. One of the measures recommended to improve diagnostics of enteroviral (non-polio) infections was virology screening of children with suspected sepsis in case of unidentified etiology. It was established that etiological decoding of nosocomial outbreaks was impossible without applying pathogen-specific diagnostic tools, mainly nested RT-PCR and direct sequencing of followed by subsequent phylogenetic analysis

Risk-oriented approach in analyzing epidemiologic situation with incidence with tick-borne encephalitis on endemic territories

Sverdlovsk region is a zone with a strenuous natural-anthropogenic focus of virus tick-borne encephalitis (TBE). Incidence with the disease has decreased by 5 times over the last 20 years due to mass vaccination among population. Since 2015 incidence with TBE has remained steady at fewer than 3 cases per 100,000 people. However, over the last 10 years incidence with TBE has been decreasing at a significantly slower rate due to a considerable growth in number of immune people (from 68 % in 2007 to 84.99 % in 2018). Analysis revealed that probability of the disease after a person had been bitten by a tick was quite different on different territories in the region. Our research goal was to develop a procedure for ranking administrative territories as per risks of clinical TBE occurrence among people bitten by ticks. We took a number of people bitten by ticks per one TBE case as our risk parameter. Our analysis revealed that average regional risk reached its maximum values (1:40–1:50) in years prior to implementation of mass vaccination against TBE. As a number of immune people grew, risk fell by 6 times (just 1 TBE case per 319 bitten people in 2018). Average regional risk was taken as to be equal to 1. We ranked administrative territories as per their risk index values (a ratio of a territorial risk to average regional one). We showed that ranking of TBE-endemic territories as per their risk index allowed implementing a differentiated approach to planning and organizing efficient preventio