Nour Eissa

• BVetMed, PGDip, MVSc, PhDs
• Vet Surgeon at Kenaston Veterinary Hospital

Stress of aquatic animals occurs due to physical and physiological disturbances in the aquatic environment or system when transportation, crowding, handling or changes of physical and chemical factors take place. There are three regulatory systems having a vital role in stress response: the neural, endocrine and immune systems. Fish exhibit multipl...

The gastrointestinal tract is the largest endocrine organ in the body and it produces a wide array of hormones and neuropeptides. Ghrelin, a 28-amino acid hormone produced mainly by the X/A-like endocrine cells in the gastric mucosa, has widespread tissue distribution and diverse physiological functions such as hormonal, orexigenic, metabolic, card...

Background: Many animal models have been developed to characterize the complexity of colonic inflammation. In dextran sodium sulfate (DSS) experimental colitis in mice the choice of reference genes is critical for accurate quantification of target genes using quantitative real time PCR (RT-qPCR). No studies have addressed the performance of refere...

2,4-Dinitrobenzene sulfonic acid (DNBS)-induced colitis is an experimental model that mimics Crohn’s disease. Appropriateness of reference genes is crucial for RT-qPCR. This is the first study to determine the stability of reference gene expression (RGE) in mice treated with DNBS. DNBS experimental Colitis was induced in male C57BL/6 mice. RNA was...

Retinoic acid (RA), an active metabolite of vitamin A, has shown potential therapeutic immunomodulatory properties. Allogeneic mesenchymal stem cells (MSCs)-based therapy is an effective approach to induce tissue healing and regeneration in many equine orthopedic conditions. However, MSCs-based therapies induced inflammatory responses in vivo. This...

In recent years, the interplay between the development and function of the central nervous system and the immune system in the homeostatic and pathological state has become evident. Thus, understanding the crosstalk between the immune system and cerebellar development and functions has noticeable implications for managing neurodevelopmental, neurod...

Background Ulcerative colitis (UC) is a chronic and acute inflammatory disorder of the colon linked to dysregulated gut mucosal immune response and compromised colonic epithelial barrier function and integrity. Chromogranin-A (CHGA), a pro-peptide secreted by enteroendocrine cells, is highly expressed in colonic tissues of patients with UC. Elevate...

Background: Chromofungin (CHR: chromogranin-A 47-66) is a chromogranin-A derived peptide with anti-inflammatory and anti-microbial properties. Ulcerative colitis (UC) is characterized by a colonic decrease of CHR and a dysregulation of dendritic CD11c+ cells. Aim: To investigate the association between CHR treatment and dendritic cells (DCs)-rel...

Ulcerative colitis (UC) is characterized by modifying alternatively activated macrophages (AAM) and epithelial homeostasis. Chromogranin-A (CHGA), released by enterochromaffin cells, is elevated in UC and is implicated in inflammation progression. CHGA can be cleaved into several derived peptides, including pancreastatin (PST), which is involved in...

Background: Ulcerative colitis (UC) is characterized by altered chromogranin-A (CHGA), alternatively activated macrophages (M2) and intestinal epithelial cells (IECs). We previously demonstrated that CHGA is implicated in colitis progression by regulating the macrophages. Here, we investigated the interplay between CHGA, M2, tight junctions (TJ) an...

Macrophages are professional innate immune cells that are broadly disseminated throughout the body, shape various innate and adaptive immune responses, and play crucial roles in inflammation, homeostasis, wound healing, and tissue remodelling. According to their surrounding microenvironments, macrophages can differentiate themselves in different ph...

The pro-inflammatory mediator receptor activator of nuclear factor-kappa B ligand (RANKL) plays a significant role in the development of rheumatoid arthritis; however, its role in inflammatory bowel disease is unknown. Genome-wide association meta-analysis for Crohn’s disease (CD) identified a variant near the TNFSF11 gene that encodes RANKL and CD...

Sleep disorders are progressively common and sometimes are associated with aberrant regulation of the adaptive and innate immune responses. Sleep interruption can increase the inflammatory burden by enhancing the pro-inflammatory cytokines particularly in patients with chronic diseases such as inflammatory bowel disease (IBD). IBD is a chronic infl...

Background Development of ulcerative colitis is associated with epithelial apoptosis mediated by p53-apoptotic pathway through the activation B-cell lymphoma 2 (Bcl-2), Bcl-2 associated-X protein (BAX) and Bcl-2 antagonist/killer-1 (BAK1) proteins. Chromofungin (CHR), a chromogranin-A derived peptide expressing a cell penetrating peptide motif, dec...

Background Ulcerative colitis (UC)is characterized by distinct changes in the gut microbiome and elevated chromogranin-A (CHGA) level, which seem to be a relevant pathogenetic mechanism.CHGA, a prohormone produced by enterochromaffin (EC) cells and cleaved into several bioactive peptides, regulates experimental colonic inflammation. In the rodent,...

Semaphorin3E (SEMA3E) has emerged as an axon-guiding molecule that regulates various biological processes including the immune responses and apoptosis. However, its role in the pathophysiology of colitis remains elusive. We investigated the role of SEMA3E in intestinal epithelial cells (IECs) activation, using biopsies from patients with active ulc...

Background and Purpose An alteration in the communication between the innate and adaptive immune cells is a hallmark of ulcerative colitis (UC). Semaphorin‐3E (SEMA3E), a secreted guidance protein, regulates various immune responses. Experimental Approach We investigated the expression of SEMA3E in colonic biopsies of active UC patients and its me...

Background Chromogranin-A produced by epithelial enterochromaffin cells is implicated in the development of ulcerative colitis (UC). In an animal model of UC, the lack of CHGA regulates the plasticity of macrophages and p/53 caspase activation in colitis. Over the last years, progresses have been done in understanding the implications of multiple c...

Background Chromogranin-A (CHGA), alternatively activated macrophages (M2), and intestinal epithelial cells (IECs) play a significant role during the progression of inflammatory bowel disease (IBD) with M2 being able to regulate IECs. Previously, we demonstrated that chromofungin and catestatin, CHGA-derived peptides, regulate epithelial cell dynam...

Chronic enteropathy (CE) in dogs is a chronic and relapsing immunopathology, of unknown etiology, that usually manifests with a plethora of clinical signs reflecting the underlying heterogeneity in its pathogenesis. Yet, alterations of the mucosal immune responses and the gut microbiota composition are thought to play an essential role in disease....

Introduction: Inflammatory bowel disease (IBD) is characterized by aberrant regulation of tight junctions (TJ), which leads to intestinal barrier defects. Signal transducer and activator of transcription 3 (STAT3) and interleukin (IL)-8/18 have a pivotal role in intestinal epithelial cells (IEC) for a restoration of gut mucosal barrier defect durin...

Standard curves of foxl2 and 18S rRNA gene indicating a linear relationship between threshold cycle (CT) and gene copy number (concentration, copies μL-1). Eff %, PCR efficiency.

Ulcerative colitis (UC) is characterized by aberrant regulation of tight junctions (TJ), signal transducer and activator of transcription 3 (STAT3), and interleukin (IL)-8/18, which lead to intestinal barrier defects. Catestatin (CST), an enterochromaffin-derived peptide, regulates immune communication and STAT-3 in the inflamed intestine. Here, we...

The PI 3-kinases (PI3K) are essential mediators of chemokine receptor signaling necessary for migration of chronic lymphocytic leukemia (CLL) cells and their interaction with tissue-resident stromal cells. While the PI3Kδ-specific inhibitor idelalisib shows efficacy in treatment of CLL and other B cell malignancies, the function of PI3Kγ has not be...

Exposure to stress induces a series of response and influences a wide range of biological processes including sex differentiation in fish. The present work investigated the molecular and physiological response to thermal stress throughout the early development stage covering the whole period of sex differentiation of bluegill, Lepomis macrochirus....

Stress enhances the disease susceptibility in fish by altering the innate immune responses, which are essential defense mechanisms. The use of probiotics is increasingly popular in the aquaculture industry. Yellow perch is a promising candidate for aquaculture. We investigated the efficiency of a mixed Bacillus species in minimizing the potential p...

The gastrointestinal tract is the largest endocrine organ that produces a broad range of active peptides. Mucosal changes during inflammation alter the distribution and products of enteroendocrine cells (EECs) that play a role in immune activation and regulation of gut homeostasis by mediating communication between the nervous, endocrine and immune...

The gastrointestinal tract is the largest endocrine organ that produces a broad range of active peptides. Mucosal changes during inflammation alter the distribution and products of enteroendocrine cells (EECs) that play a role in immune activation and regulation of gut homeostasis by mediating communication between the nervous, endocrine and immune...

Background Ulcerative colitis (UC) is characterized by altered levels of chromogranin-A (CHGA) and a dysregulation of dendritic cells (DCs). CHGA, a prohormone protein, can be cleaved into several bioactive peptides including chromofungin (CHR: CHGA47-66) encoded by CHGA Exon-IV. Previously, we demonstrated that CHR is reduced in active UC patients...

Background Ulcerative colitis (UC) is characterized by an alterations of tight junction (TJ) barrier and immune responses that result in abnormal passages of exogenous antigens such as gut-derived bacterial lipopolysaccharides (LPS). Semaphorin-3E (Sema3E) and its receptor plexin D1 (PLXD1R) are key regulators of epithelia and immune systems Aims...

Background Chromogranin-A (CgA) is elevated in inflammatory bowel disease (IBD) and in murine models of colitis. CgA produced by enteroendocrine cells can be cleaved in several peptides including the immunoregulatory pancreastatin (PTS: CgA273-301). Macrophages (Mo) play a major role in IBD through an impaired transition from a pro-inflammatory (cl...

Background Chromogranin-A (CHGA) levels are increased in inflammatory bowel disease (IBD) and murine models of colitis. CHGA is cleaved in several peptides including the immunoregulatory pancreastatin (PST: CHGA273-301), which encodes by CHGA exon-VII. Classically activated macrophages (M1) and signal transducer and activator of transcription (STAT...

Background Inflammatory bowel diseases (IBD) involve an increase of dendritic cells (DC) infiltration and cytokines production. Recently, semaphorins have been implicated in inflammation and cell migration and has emerged as an essential axis in DC immune responses. Aims This study aims to determine the role of Sema3E on DC regulation during colit...

Chromogranin-A (CHGA) is elevated in inflammatory bowel disease (IBD), but little is known about its role in colonic inflammation. IBD is associated with impaired functions of macrophages and increased apoptosis of intestinal epithelial cells. We investigated CHGA expression in human subjects with active ulcerative colitis (UC) and the underlying m...

Ulcerative colitis (UC) is characterized by a functional dysregulation of alternatively activated macrophage (AAM) and intestinal epithelial cells (IECs) homeostasis. Chromogranin-A (CHGA) secreted by neuroendocrine cells is implicated in intestinal inflammation and immune dysregulation. CHGA undergoes proteolytic processing to generate CHGA-derive...

Ulcerative colitis (UC) is characterized by a functional dysregulation of alternatively activated macrophage (AAM) and intestinal epithelial cells (IECs) homeostasis. Chromogranin-A (CHGA) secreted by neuroendocrine cells is implicated in intestinal inflammation and immune dysregulation. CHGA undergoes proteolytic processing to generate CHGA-derive...

Stress is a major factor that causes diseases and mortality in the aquaculture industry. The goal was to analyze the expression of stress-related biomarkers in response to different stressors in yellow perch, which is an important aquaculture candidate in North America and highly sensitive to handling in captivity. Three fish groups were establishe...

While there is growing awareness of a relationship between chromogranin-A (CHGA) and susceptibility to inflammatory conditions, the role of human catestatin [(hCTS); CHGA352–67] in the natural history of established inflammatory bowel disease is not known. Recently, using two different experimental models, we demonstrated that hCTS-treated mice dev...

Understanding the cross talk between the immune system and cerebellum development has noticeable implications for understanding and management of neurodevelopmental disorders. Our knowledge about cerebellar developmental maturation and remodeling is improving. Immune cells have different functions in a healthy state, but those functions are comprom...

The mammalian intestinal tract is heavily colonized with a dense, complex, and diversified microbial populations. In healthy individuals, an array of epithelial antimicrobial agents is secreted in the gut to aid intestinal homeostasis. Enterochromaffin cells (EC) in the intestinal epithelium are a major source of chromogranin A (CgA), which is a pr...

The mammalian intestinal tract is heavily colonized with a dense, complex, and diversified microbial populations. In healthy individuals, an array of epithelial antimicrobial agents is secreted in the gut to aid intestinal homeostasis. Enterochromaffin cells (EC) in the intestinal epithelium are a major source of chromogranin A (CgA), which is a pr...

Amplification efficiency for the primers of candidate reference genes. The X-axis represents the log10 cDNA dilution series, and the Y-axis represents the cycle threshold (Ct). The primer efficiency (E) is calculated by [10(1/-S)-1] × 100%, where S represents the slope of the linear regression line. Roch Light Cycler Software was used for calculati...

Effect of reference gene selection on the relative expression of colonic TNF-α (A) and IL-1β (B). Target gene expression was normalized against the 13 reference genes using the difference in threshold cycle (ΔCt) calculation method. Significant differences between control and inflamed colon were seen only with the stable reference genes. Student’s...

Stability of Reference Genes for Messenger RNA Quantification by Real-Time PCR in Mouse Dextran Sodium Sulfate Experimental Colitis Nour Eissa, Hayam Hussein, Mohammad F. Rabbi, Peris M. Munyaka, Azin Khafipour, Charles N. Bernstein, Jean-Eric Ghia Background: Many animal models have been developed to characterize the complexity of colonic inflam...

Postnatal maturation of the immune system is largely driven by exposure to microbes, and thus the nature of intestinal colonization may be associated with development of childhood diseases that may persist into adulthood. We investigated whether antepartum antibiotic (ATB) therapy can increase offspring susceptibility to experimental colitis throug...

Background and aims: Postnatal maturation of the immune system is largely driven by exposure to microbes, and thus the nature of intestinal colonization may be associated with development of childhood diseases that may persist into adulthood. We investigated whether antepartum antibiotic (ATB) therapy can increase offspring susceptibility to exper...

Centrifuge the primer tube for 10 minutes at 12000 RPM (Do not forget this, it is so important). This will allow the primer to be settled at the bottom.  First dissolve fresh primer with the 10X volume as its concentration (Always the concentration is written on the tube or certificate Analysis of the primers in nmole) : Example for 25 nmoles of p...

Global temperature climate changes affect stress, immune function and growth of aquatic animals. The aim of this study was to investigate the effect of different temperatures on oxidative stress, thermal stress, immune response and growth in bluegill sunfish (Lepomis macrochirus). The experiment included four groups that were exposed to different w...

Global temperature climate changes affect stress, immune function and growth of aquatic animals. The aim of this study was to investigate the effect of different temperatures on oxidative stress, thermal stress, immune response and growth in bluegill sunfish (Lepomis macrochirus). The experiment included four groups that were exposed to different w...

In the present study a commercial probiotic Fishery Prime TM , acting as water soluble probiotic, was administered to Yellow Perch (Perca flavescens) for 6 weeks. The probiotic effect on growth and growth regulated genes were evaluated with respect to fish group fed on commercial feed (control group). Measures of body weight were performed to asses...

The main goal of this work was to determine the effect of water soluble commercial probiotic on the transcriptional analysis of the anti-oxidative status of yellow perch. Glutathione peroxidase (GPX), superoxide dismutase (SOD), and cytochrome oxidase subunit I (COI) were analyzed in yellow perch at 25and50 days after receiving the probiotic with r...

The use of Pseudomonas fluorscens isolates as biological control agents against two fish pathogens; Pseudomonas angulliseptica and Streptococcus faecium in Nile tilapia were investigated in vivo and vitro. Pseudomonas fluorscens biovars I, II & III were tested in vitro using the agar diffusion method and showed effectiveness in inhibiting growth of...

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Pseudomonas fluorescens biovars were isolated from Oreochromis niloticus at Qaroun Lake, Egypt. Microorganisms were added to basal diet with 30 % protein to assess their probiotic properties on growth-performance, hematological parameters, no-specific immunity and survival rate. Tilapia (2.93 ± 0.22 g) were distributed into four equal groups, three...

Yellow Perch Perca flavescens were subjected to handling stress and salt treatments at different temperatures to determine their physiological changes. Yellow Perch, held at 8–10°C, were divided into three groups with four replicates and subjected to water temperatures of 14, 20, and 26°C to acclimate. Then they were subjected to acute handling twi...

Twenty four New-Zealand White rabbit of both sexes (12 males and 12 females), 4 weeks old, with nearly equal live BW at the beginning of the experiment were randomly allotted to three groups of 8 rabbit each (4 males and 4 females). Three groups were established according to the cage floor type. The first group was raised on wire mesh cage floor th...

The objective of this study was to evaluate previously isolated non pathogenic Pseudomonas fluorescens biovars inhibitory effect against pathogenic A. hydrophila in vitro and in vivo. The results showed that P. fluorescens biovars have in vitro antibacterial inhibitory effect against A. hydrophila. Also, feeding O. niloticus diet containing P. fluo...

Oreochromis niloticus from Qaroun and El Rayan lakes were collected and examined for the presence of pseudomonas species. The organisms were found in 30.83% of the 480 examined fish with some fish, especially during the episode of mass mortality showing, typical signs of pseudomonas septicemia; redness all over the body, abdominal swelling, eyes cl...

Bluegill sunfish (Lepomis macrochirus) is an important recreational and aquaculture fish species in US. Much interest has been generated concerning the development of monosex male populations of bluegill due to their more rapid growth capacity relative to females. The methods involved to develop monosex population require a comprehensive understand...

Two experiments were conducted to explore the effect of handling stress on yellow perch (Perca ) subjected to different water temperatures. The first experiment was to determine the optimum temperature for handling of yellow perch with minimal stress. Yellow perch were divided into three groups with four replicates and subjected to water temperatur...