👤 Moshe Levi

Ketamine holds promise for the treatment of post-traumatic stress disorder (PTSD), but challenges remain in delivery and sustained effects. This controlled study evaluates a novel intranasal formulation, employing AmyloLipid nanovesicles (ALN) to enhance ketamine's therapeutic efficacy in a predator-scent stress (PSS) rat model of PTSD. A total of 130 rats underwent PSS or sham-PSS exposure, followed by intranasal administration of ketamine-ALN (4.8, 2.4, 1.2 and 0.6 mg/kg), unloaded-ALN, saline, or standard ketamine three times weekly for two weeks, starting seven days post-trauma. Behavioral assessments, including the elevated plus maze, acoustic startle response, and contextual freezing tests, were complemented by immunohistochemical and Golgi-Cox analyses of hippocampal and paraventricular nucleus (PVN) tissues. Low-dose ketamine-ALN (0.6 mg/kg) significantly reduced anxiety-like behaviors, hyperarousal, and the prevalence of PTSD-like responses (extreme behavior responses) by 45% compared to unloaded-ALN controls. Unlike standard ketamine, ALN-mediated delivery bypassed the blood-brain barrier, enhancing bioavailability and sustaining therapeutic benefit. Mechanistically, ketamine-ALN normalized the expression of hyperpolarization-activated cyclic nucleotide-gated (HCN1) channels-which were upregulated in the CA1 stratum lacunosum-moleculare (SLM) post-PSS-thereby stabilizing neuronal excitability. This normalization of HCN1, critical for regulating neuronal excitability and membrane potential, was accompanied by increased levels of brain-derived neurotrophic factor (BDNF) and neuropeptide Y (NPY), enhancing neuroplasticity and dendritic complexity. These findings demonstrate that ALN-based intranasal delivery of ketamine is more effective than standard administration, particularly at low doses. The results suggest that low-dose ketamine-ALN modulates a hippocampal circuit involving HCN1, BDNF, and NPY to foster adaptive stress responses. Collectively, ketamine-ALN represents a promising targeted therapy for PTSD, with HCN1 channels as a key mediator of stress-induced neuronal dysfunction and ketamine's therapeutic action, thus advancing the prospects for precision treatment of stress-related disorders. Show less

Atherosclerotic cardiovascular disease (CVD) remains a leading cause of vascular disease worldwide. Atherosclerosis is characterized by the accumulation of lipids and oxidized lipids on the blood vessel walls. Coronary artery disease (CAD) is the most common display of atherosclerotic CVD. We investigated the effects of the bioactive lipids as lyso-diacylglyceryltrimethylhomoserine (lyso-DGTS (20,5,0)) and its derivative oleoyl-N-trimethyl homoserine amide (oleoyl amide-MHS) on the properties and functionality of HDL and paraoxonase 1 (PON1) activities in the serum of individuals who exhibited arterial plaque as observed by coronary CT angiography (CCTA). The study included two independent groups comprising 40 patients who had undergone arterial CCTA scans at Ziv Medical Center for various medical indications. The CAD group included 20 patients with coronary artery plaques with luminal stenosis of more than 50 % in a major coronary vessel. The control group consisted of 20 healthy patients (patients without artery plaques). Serum samples from CAD patients exhibited lower serum PON1 and cholesterol efflux activities and higher pro-inflammatory than the control group. HDL isolated from CAD patients contains elevated levels of oxidizing lipids (specifically lyso- phosphatidyl ethanolamines and lyso-phosphocholines(compared to the control. However, incubation of the CAD patients' serum with lyso-DGTS and oleoyl amide-MHS restored the antiatherogenic activities of HDL. The lipids increased serum PON1 activities, enhanced apoB-depleted serum cholesterol-efflux activity, and elevated the serum's anti-inflammatory properties. The results of the present study suggest the potential of the bioactive lipids lyso-DGTS and oleoyl amide-MHS to attenuate atherosclerosis via the improvement of dysfunctional HDL properties and PON1 activities. Further, in-vivo experiments are needed to assess the athero-protective effect of the lipids. Show less

Alport syndrome (AS) is a genetic condition caused by a dysfunctional collagen (IV) α3α4α5 heterotrimer, leading to basement membrane instability and, ultimately, abnormalities in the kidney, inner ear, and eyes. This study aimed to characterize ocular pathology of AS by focusing on inflammatory and fibrotic markers. Col4a3tm1Dec knockout (KO) mice eyes were evaluated for the localization of collagen (IV) α3 and collagen (IV) α4, then stained for transforming growth factor-β1 (TGF-β1), TGF-β2, connective tissue growth factor (CTGF), and β-catenin. mRNA levels of the profibrotic genes S100a4, Acta2, Col1a1, Snai1, Snai2, and Twist1 were assessed using real-time reverse transcription quantitative PCR (RT-qPCR). Collagen (IV) α3 and collagen (IV) α4 were co-expressed in Descemet's and Bruch's membrane but not in the retina, lens, or other corneal substructures. Immunofluorescence quantitation revealed upregulation of TGF-β1 in the anterior lens and TGF-β2 in the retina of KO eyes. Conversely, CTGF and β-catenin were shown to be elevated in the corneal epithelium but not the retina or lens. RT-qPCR showed an increase in the transcription of Acta2, Col1a1, and Snai2 in the retinas and Snai2 in anterior segments of KO mice. Col4a3 KO mice exhibited a differential inflammatory and profibrotic response in the cornea, retina, and lens, which may play a role in the ocular pathology of AS. Show less

Cellular lineage tracking provides a means to observe population makeup at the clonal level, allowing exploration of heterogeneity, evolutionary and developmental processes and individual clones' relative fitness. It has thus contributed significantly to understanding microbial evolution, organ differentiation and cancer heterogeneity, among others. Its use, however, is limited because existing methods are highly specific, expensive, labour-intensive, and, critically, do not allow the repetition of experiments. To address these issues, we developed gUMI-BEAR (genomic Unique Molecular Identifier Barcoded Enriched Associated Regions), a modular, cost-effective method for tracking populations at high resolution. We first demonstrate the system's application and resolution by applying it to track tens of thousands of Saccharomyces cerevisiae lineages growing together under varying environmental conditions applied across multiple generations, revealing fitness differences and lineage-specific adaptations. Then, we demonstrate how gUMI-BEAR can be used to perform parallel screening of a huge number of randomly generated variants of the Hsp82 gene. We further show how our method allows isolation of variants, even if their frequency in the population is low, thus enabling unsupervised identification of modifications that lead to a behaviour of interest. Show less

The challenging environment of prehospital casualty care demands providers to make prompt decisions and to engage in lifesaving interventions, occasionally without them being adequately experienced. Telementoring based on augmented reality (AR) devices has the potential to decrease the decision time and minimise the distance gap between an experienced consultant and the first responder. The purpose of this study was to determine whether telementoring with AR glasses would affect chest thoracotomy performance and self-confidence of inexperienced trainees. Two groups of inexperienced medical students performed a chest thoracotomy in an ex vivo pig model. While one group was mentored remotely using HoloLens AR glasses, the second performed the procedure independently. An observer assessed the trainees' performance. In addition, trainees and mentors evaluated their own performance. Quality of performance was found to be superior with remote guidance, without significant prolongation of the procedure (492 s vs 496 s, p=0.943). Moreover, sense of self-confidence among participant was substantially improved in the telementoring group in which 100% of the participants believed the procedure was successful compared with 40% in the control group (p=0.035). AR devices may have a role in future prehospital telementoring systems, to provide accessible consultation for first responders, and could thus positively affect the provider's confidence in decision-making, enhance procedure performance and ultimately improve patient prognosis. That being said, future studies are required to estimate full potential of this technology and additional adjustments are necessary for maximal optimisation and implementation in the field of prehospital care. Show less

Liver X receptors (LXRs) α and β are nuclear hormone receptors that are widely expressed in the kidney. They promote cholesterol efflux from cells and inhibit inflammatory responses by regulating gene transcription. Here, we hypothesised (1) that LXR deficiency would promote renal decline in a mouse model of diabetes by accelerating intraglomerular cholesterol accumulation and, conversely, (2) that LXR agonism would attenuate renal decline in diabetes. Diabetes was induced with streptozotocin (STZ) and maintained for 14 weeks in Lxrα/β (+/+) (Lxrα, also known as Nr1h3; Lxrβ, also known as Nr1h2) and Lxrα/β (-/-) mice. In addition, STZ-injected DBA/2J mice were treated with vehicle or the LXR agonist N,N-dimethyl-hydroxycholenamide (DMHCA) (80 mg/kg daily) for 10 weeks. To determine the role of cholesterol in diabetic nephropathy (DN), mice were placed on a Western diet after hyperglycaemia developed. Even in the absence of diabetes, Lxrα/β (-/-) mice exhibited a tenfold increase in the albumin:creatinine ratio and a 40-fold increase in glomerular lipid accumulation compared with Lxrα/β (+/+) mice. When challenged with diabetes, Lxrα/β (-/-) mice showed accelerated mesangial matrix expansion and glomerular lipid accumulation, with upregulation of inflammatory and oxidative stress markers. In the DN-sensitive STZ DBA/2J mouse model, DMHCA treatment significantly decreased albumin and nephrin excretion (by 50% each), glomerular lipids and plasma triacylglycerol (by 70%) and cholesterol (by 48%); it also decreased kidney inflammatory and oxidative stress markers compared with vehicle-treated mice. These data support the idea that LXR plays an important role in the normal and diabetic kidney, while showing that LXR, through its inhibitory effect on inflammation and cholesterol accumulation in glomeruli, could also be a novel therapeutic target for DN. Show less

Endothelial progenitor cells (EPCs), critical for mediating vascular repair, are dysfunctional in a hyperglycemic and/or hypercholesterolemic environment. Their dysfunction contributes to the progression of diabetic macro- and microvascular complications. Activation of "cholesterol-sensing" nuclear receptors, the liver X receptors (LXRα/LXRβ), protects against atherosclerosis by transcriptional regulation of genes important in promoting cholesterol efflux and inhibiting inflammation. We hypothesized that LXR activation with a synthetic ligand would correct diabetes-induced EPC dysfunction and improve diabetic retinopathy. Studies were performed in streptozotocin (STZ)-injected DBA/2J mice fed a high-fat Western diet (DBA/STZ/WD) and treated with the LXR agonist GW3965 and in LXRα(-/-), LXRβ(-/-), and LXRα/β(-/-) mice. Retinas were evaluated for number of acellular capillaries and glial fibrillary acidic protein (GFAP) immunoreactivity. Bone marrow EPCs were analyzed for migratory function and gene expression. Compared with vehicle-treated DBA/STZ/WD mice, GW3965 treated mice showed fewer acellular capillaries and reduced GFAP expression. These mice also exhibited enhanced EPC migration and restoration of inflammatory and oxidative stress genes toward nondiabetic levels. LXRα(-/-), LXRβ(-/-), and LXRα/β(-/-) mice developed acellular capillaries and EPC dysfunction similar to the DBA/STZ/WD mice. These studies support a key role for LXR in retinal and bone marrow progenitor dysfunction associated with type 1 diabetes. LXR agonists may represent promising pharmacologic targets for correcting retinopathy and EPC dysfunction. Show less

Vascular calcification is recognized as an independent predictor of cardiovascular mortality, particularly in subjects with chronic kidney disease. However, the pathways by which dysregulation of lipid and mineral metabolism simultaneously occur in this particular population remain unclear. We have shown that activation of the farnesoid X receptor (FXR) blocks mineralization of bovine calcifying vascular cells (CVCs) and in ApoE knock-out mice with 5/6 nephrectomy. In contrast to FXR, this study showed that liver X receptor (LXR) activation by LXR agonists and adenovirus-mediated LXR overexpression by VP16-LXRα and VP16-LXRβ accelerated mineralization of CVCs. Conversely, LXR inhibition by dominant negative (DN) forms of LXRα and LXRβ reduced calcium content in CVCs. The regulation of mineralization by FXR and LXR agonists was highly correlated with changes in lipid accumulation, fatty acid synthesis, and the expression of sterol regulatory element binding protein-1 (SREBP-1). The rate of lipogenesis in CVCs through the SREBP-1c dependent pathway was reduced by FXR activation, but increased by LXR activation. SREBP-1c overexpression augmented mineralization in CVCs, whereas SREBP-1c DN inhibited alkaline phosphatase activity and mineralization induced by LXR agonists. LXR and SREBP-1c activations increased, whereas FXR activation decreased, saturated and monounsaturated fatty acids derived from lipogenesis. In addition, we found that stearate markedly promoted mineralization of CVCs as compared with other fatty acids. Furthermore, inhibition of either acetyl-CoA carboxylase or acyl-CoA synthetase reduced mineralization of CVCs, whereas inhibition of stearoyl-CoA desaturase induced mineralization. Therefore, a stearate metabolite derived from lipogenesis might be a risk factor for the development of vascular calcification. Show less

In Akita and OVE26 mice, two genetic models of type 1 diabetes, diabetic nephropathy is characterized by mesangial expansion and loss of podocytes, resulting in glomerulosclerosis and proteinuria, and is associated with increased expression of profibrotic growth factors, proinflammatory cytokines, and increased oxidative stress. We have also found significant increases in renal triglyceride and cholesterol content. The increase in renal triglyceride content is associated with 1) increased expression of sterol regulatory element-binding protein (SREBP)-1c and carbohydrate response element-binding protein (ChREBP), which collectively results in increased fatty acid synthesis, 2) decreased expression of peroxisome proliferator-activated receptor (PPAR)-alpha and -delta, which results in decreased fatty acid oxidation, and 3) decreased expression of farnesoid X receptor (FXR) and small heterodimer partner (SHP). The increase in cholesterol content is associated with 1) increased expression of SREBP-2 and 3-hydroxy-3-methylglutaryl (HMG)-CoA reductase, which results in increased cholesterol synthesis, and 2) decreased expression of liver X receptor (LXR)-alpha, LXR-beta, and ATP-binding cassette transporter-1, which results in decreased cholesterol efflux. Our results indicate that in type 1 diabetes, there is altered renal lipid metabolism favoring net accumulation of triglycerides and cholesterol, which are driven by increases in SREBP-1, ChREBP, and SREBP-2 and decreases in FXR, LXR-alpha, and LXR-beta, which may also play a role in the increased expression of profibrotic growth hormones, proinflammatory cytokines, and oxidative stress. Show less

The principal goal of the Israel Structural Proteomics Center (ISPC) is to determine the structures of proteins related to human health in their functional context. Emphasis is on the solution of structures of proteins complexed with their natural partner proteins and/or with DNA. To date, the ISPC has solved the structures of 14 proteins, including two protein complexes. It has adopted automated high-throughput (HTP) cloning and expression techniques and is now expressing in Escherichia coli, Pichia pastoris and baculovirus, and in a cell-free E. coli system. Protein expression in E. coli is the primary system of choice in which different parameters are tested in parallel. Much effort is being devoted to development of automated refolding of proteins expressed as inclusion bodies in E. coli. The current procedure utilizes tagged proteins from which the tag can subsequently be removed by TEV protease, thus permitting streamlined purification of a large number of samples. Robotic protein crystallization screens and optimization utilize both the batch method under oil and vapour diffusion. In order to record and organize the data accumulated by the ISPC, a laboratory information-management system (LIMS) has been developed which facilitates data monitoring and analysis. This permits optimization of conditions at all stages of protein production and structure determination. A set of bioinformatics tools, which are implemented in our LIMS, is utilized to analyze each target. Show less

Carbohydrate response element-binding protein (ChREBP) is a rat homolog of human Williams-Beuren syndrome region 14 and a member of the basic helix-loop-helix leucine zipper transcription factor family. Its activation was found to be inducible by carbohydrate in the liver nuclear extracts from rats fed a high-sucrose diet. ChREBP is able to bind to the carbohydrate response element on the promoter of L-type pyruvate kinase and initiate the gene transcription. The detailed expression profile and transcriptional regulation of the ChREBP gene in adipocytes have not been characterized. In the present study, we provide evidence showing that 1) the ChREBP gene is expressed in differentiated 3T3-L1 adipocytes and rat adipose tissue; 2) insulin, glucose, and the antidiabetic agent troglitazone can significantly upregulate the gene expression of ChREBP in 3T3-L1 adipocytes, whereas free fatty acids suppress its expression in this cell type; 3) fasting followed by refeeding with a high-carbohydrate diet resulted in a 10-fold increase of ChREBP mRNA level in rat adipose tissue; and 4) ChREBP expression in adipose tissue is not significantly affected by the diabetic state. Taken together, the results we present are consistent with the idea that ChREBP is an important modulator of adipocyte biology and that its expression in adipose tissue is subject to combined regulation by glucose and insulin in vivo. The induction of ChREBP may serve as a novel pharmacological pathway for troglitazone-mediated hypoglycemic effects in vivo. Show less