Plasmodium chabaudi Infection Alters Intestinal Morphology and Mucosal Innate Immunity in Moderately Malnourished Mice.

Plasmodium falciparum is a protozoan parasite which causes malarial disease in humans. Infections commonly occur in sub-Saharan Africa, a region with high rates of inadequate nutrient consumption resulting in malnutrition. The complex relationship between malaria and malnutrition and their effects on gut immunity and physiology are poorly understood. Here, we investigated the effect of malaria infection in the guts of moderately malnourished mice. We utilized a well-established low protein diet that is deficient in zinc and iron to induce moderate malnutrition and investigated mucosal tissue phenotype, permeability, and innate immune response in the gut. We observed that the infected moderately malnourished mice had lower parasite burden at the peak of infection, but damaged mucosal epithelial cells and high levels of FITC-Dextran concentration in the blood serum, indicating increased intestinal permeability. The small intestine in the moderately malnourished mice were also shorter after infection with malaria. This was accompanied with lower numbers of CD11b+ macrophages, CD11b+CD11c+ myeloid cells, and CD11c+ dendritic cells in large intestine. Despite the lower number of innate immune cells, macrophages in the moderately malnourished mice were highly activated as determined by MHCII expression and increased IFNγ production in the small intestine. Thus, our data suggest that malaria infection may exacerbate some of the abnormalities in the gut induced by moderate malnutrition.

Transcriptomic profile of VEGF-regulated genes in human cervical epithelia.

Cervical epithelial cells play a central role in cervical remodeling (CR) during pregnancy and cervical events during menstrual cycle, including mounting physical and immunological barriers, proliferation and differentiation, maintenance of fluid balance, and likely in withstanding the mechanical force exerted by the growing fetus prior to term. In the present study, we attempt to decipher the specific roles of VEGF in fetal human cervical epithelial cells by delineating VEGF signature genes using RNA sequencing in order to characterize the specific biological effects of VEGF in these cells.Out of a total of 25,000 genes screened, 162 genes were found to be differentially expressed in human cervical epithelial cells, of which 12 genes were found to be statistically significantly differentially expressed. The differentially expressed genes (162) were categorized by biological function, which included (1) proliferation, (2) immune response, (3) structure/matrix, (4) mitochondrial function, and (5) cell adhesion/communication and others (pseudogenes, non-coding RNA, miscellaneous genes, and uncharacterized genes). We conclude that VEGF plays a key role in CR by altering the expression of genes that regulate proliferation, immune response, energy metabolism and cell structure, and biological processes that are essential to development and likely CR.

Moringa oleifera treatment increases Tbet expression in CD4+ T cells and remediates immune defects of malnutrition in Plasmodium chabaudi-infected mice.

BACKGROUND: Malaria is a worldwide problem that affects millions of people yearly. In rural areas where anti-malarial drugs are not easily accessible, many people use herbal treatments, such as Moringa oleifera, to treat a variety of diseases and ailments including malaria. While Moringa is reported to possess potent and curative anti-malarial properties, previous studies have mostly been restricted to assessment of parasitaemia. In this study, the effect of Moringa on malaria immunity in a murine model was investigated. METHODS: Using a high dose (60 mg/mouse) for a short time (7 days) or low dose Moringa (30 mg/mouse) for a longer time (3 weeks), cytokine production, and Tbet expression by effector CD4+ T cells (Teff) were determined. Mice were also treated with Moringa after infection (curatively) or before infection (prophylactically) to determine the effect of the plant extract on parasitaemia and immunity. Given that Moringa also possess many nutritional benefits, the contribution of Moringa on malnourished malaria infected mice was determined. Malnutrition was induced by limiting access to food to only 4 h a day for 4 weeks, while control mice had unlimited access to mouse laboratory chow. All data was collected by flow cytometry and analysed using one-Way ANOVA or two tailed Student's t test. RESULTS: Moringa-treated mice had increased numbers of effector CD4+ T cells accompanied by an increase in Tbet expression compared to control untreated mice. Mice that were treated with Moringa curatively also exhibited increased effector CD4+ T cell numbers, IFN-gamma and TNF secretion. Interestingly, the mice that were treated prophylactically had significantly higher Tbet expression. In the absence of adaptive immunity, high parasitaemia was observed in the RAG1 knockout mice. The food limited mice (malnourished) had reduced numbers of CD4+ T cells, TNF proportions, and significantly greater Tbet expression compared to the control group. Supplementation with Moringa in the limited group slightly restored CD4+ T cell activation, IL-2, and IL-10 production. CONCLUSIONS: Taken together, these data suggest that Moringa treatment leads to increased CD4+ T cell activation, Th1 differentiation and production of pro-inflammatory cytokines after malaria infection. Thus, Moringa may be immunologically useful in the treatment of malaria and malnutrition. Further investigations are required to identify the active components in Moringa.

Immunity in the Cervix: Interphase between Immune and Cervical Epithelial Cells.

The cervix is divided into two morphologically and immunologically distinct regions, namely, (1) the microbe-laden ectocervix, which is proximal to the vagina, and (2) the "sterile" endocervix, which is distal to the uterus. The two cervical regions are bordered by the cervical transformation zone (CTZ), an area of changing cells, and are predominantly composed of cervical epithelial cells. Epithelial cells are known to play a crucial role in the initiation, maintenance, and regulation of innate and adaptive response in collaboration with immune cells in several tissue types, including the cervix, and their dysfunction can lead to a spectrum of clinical syndromes. For instance, epithelial cells block progression and neutralize or kill microorganisms through multiple ways. These (ways) include mounting physical (intercellular junctions, secretion of mucus) and immune barriers (pathogen-recognition receptor-mediated pathways), which collectively and ultimately lead to the release of specific chemokines and or cytokines. The cytokines subsequently recruit subsets of immune cells appropriate to a particular immune context and response, such as dendritic cells (DCs), T, B, and natural killer (NK) cells. The immune response, as most biological processes in the female reproductive tract (FRT), is mainly regulated by estrogen and progesterone and their (immune cells) responses vary during different physiological phases of reproduction, such as menstrual cycle, pregnancy, and post menopause. The purpose of the present review is to compare the immunological profile of the mucosae and immune cells in the ecto- and endocervix and their interphase during the different phases of female reproduction.

Mechanobiology of mice cervix: expression profile of mechano-related molecules during pregnancy.

There is a known reciprocation between the chronic exertion of force on tissue and both increased tissue density (e.g., bone) and hypertrophy (e.g., heart). This can also be seen in cervical tissue where the excessive gravitational forces associated with multiple fetal pregnancies promote preterm births. While there is a well-known regulation of cervical remodeling (CR) by sex steroid hormones and growth factors, the role of mechanical force is less appreciated. Using proteome-wide technology, we previously provided evidence for the presence of and alteration in mechano-related signaling molecules in the mouse cervix during pregnancy. Here, we profile the expression of select cytoskeletal factors (filamin-A, gelsolin, vimentin, actinin-1, caveolin-1, transgelin, keratin-8, profilin-1) and their associated signaling molecules [focal adhesion kinase (FAK) and the Rho GTPases CDC42, RHOA, and RHOB] in cervices of pregnant mice by real-time PCR and confocal immunofluorescence microscopy. Messenger RNA and protein levels increased for each of these 12 factors, except for 3 (keratin-8, profilin-1, RHOA) that decreased during the course of pregnancy and this corresponded with an increase in gravitational force exerted by the fetus on the cervix. We therefore conclude that size or weight of the growing fetus likely plays a key role in CR through mechanotransduction processes.

A proteomic profile of postpartum cervical repair in mice.

A timely and complete uterine cervical tissue repair postpartum is of necessity to prevent obstetrical complications, such as cervicitis, ectropion, hemorrhage, repeated miscarriages or abortions and possibly preterm labor and malignancies. We recently characterized the morphological alterations, as well as changes in angiogenic expression profile in a mice uterine cervix during the immediate postpartum period. Here, we build on this previous study using a proteomic analysis to profile postpartum tissue changes in mice cervix during the same period, the first 48 h of postpartum. The current proteomics data reveal a variable expression of several intermediate filaments, cytoskeletal modulators and proteins with immune and/or wound-healing properties. We conclude that postpartum cervical repair involves a rapid and tightly regulated balance between a host of biological factors, notably between anti- and pro-inflammatory factors, executed by the M1 and M2 macrophage cells, as revealed by proteomics and verified by confocal immunofluorescence. Future studies will assess the suitability of some of the key proteins identified in this study as potential markers for determining the phase of postpartum cervical repair in obstetrical complications, such as cervical lacerations.

Landiolol hydrochloride ameliorates acute lung injury in a rat model of early sepsis through the suppression of elevated levels of pulmonary endothelin-1.

Among the dysfunctions and pathologies associated with sepsis, the underlying molecular mechanisms of sepsis-induced acute lung injury (ALI) are poorly understood. Endothelin (ET)-1, a potent vasoconstrictor and pro-inflammatory peptide, is known to be involved in the pathogenesis of ALI in a rat model of sepsis. Here, we investigated whether landiolol hydrochloride, an ultra-short-acting ß-blocker, plays a crucial role in ameliorating and attenuating LPS-induced ALI through modulation of the ET-1 system. Male Wistar rats at 8weeks of age were administered with either saline or lipopolysaccharide (LPS) for three hours (3h) and some of the LPS-administered rats were continuously treated with landiolol for 3h. ALI was induced by LPS, including levels of both circulatory and pulmonary TNF-α and IL-6 but [PaO2] was significantly decreased. LPS also induced a significant increase in levels of pulmonary ET-1 and ET-A receptor, but levels of ET-B receptor, which has vasodilating effects, were remarkably diminished. Further, LPS administration upregulated the pulmonary expression of HIF-1α. Finally, the treatment of LPS-administered rats with landiolol for 3h ameliorated and prevented ALI, normalized the altered levels of pulmonary ET-1 and ET-A receptors. Landiolol also induced significant down-regulation of ET-B receptor in lung tissues in the early hours (phase) of sepsis. However, Landiolol treatment had no effect on the up-regulated inflammatory mediators (TNF-α, IL-6) in both plasma and lung tissues during sepsis, and expression of pulmonary HIF-1α also remained unchanged after landiolol treatment. Collectively, these data led us to conclude that landiolol may ameliorate sepsis-induced ALI via the pulmonary ET system.

Effects of protease activated receptor (PAR)2 blocking peptide on endothelin-1 levels in kidney tissues in endotoxemic rat mode.

AIMS: Septic shock, the severe form of sepsis, is associated with development of progressive damage in multiple organs. Kidney can be injured and its functions altered by activation of coagulation, vasoactive-peptide and inflammatory processes in sepsis. Endothelin (ET)-1, a potent vasoconstrictor, is implicated in the pathogenesis of sepsis and its complications. Protease-activated receptors (PARs) are shown to play an important role in the interplay between inflammation and coagulation. We examined the time-dependent alterations of ET-1 and inflammatory cytokine, such as tumor necrosis factor (TNF)-α in kidney tissue in lipopolysaccharide (LPS)-induced septic rat model and the effects of PAR2 blocking peptide on the LPS-induced elevations of renal ET-1 and TNF-α levels. MAIN METHODS: Male Wistar rats at 8 weeks of age were administered with either saline solution or LPS at different time points (1, 3, 6 and 10h). Additionally, we treated LPS-administered rats with PAR2 blocking peptide for 3h to assess whether blockade of PAR2 has a regulatory role on the ET-1 level in septic kidney. KEY FINDINGS: An increase in ET-1 peptide level was observed in kidney tissue after LPS administration time-dependently. Levels of renal TNF-α peaked (around 12-fold) at 1h of sepsis. Interestingly, PAR2 blocking peptide normalized the LPS-induced elevations of renal ET-1 and TNF-α levels. SIGNIFICANCE: The present study reveals a distinct chronological expression of ET-1 and TNF-α in LPS-administered renal tissues and that blockade of PAR2 may play a crucial role in treating renal injury, via normalization of inflammation, coagulation and vaso-active peptide.

Dual blockade of endothelin action exacerbates up-regulated VEGF angiogenic signaling in the heart of lipopolysaccharide-induced endotoxemic rat model.

AIMS: Sepsis is a cluster of heterogeneous syndromes associated with progressive endotoxemic developments, ultimately leading to damage of multiple organs, including the heart. However, the pathogenesis of sepsis-induced myocardial dysfunction is still not fully understood. The present study is the first to examine alterations in expression of key angiogenic signaling system mediated by vascular endothelial growth factor (VEGF) in septic heart and the effects of endothelin dual blocker (ETDB) on it. MAIN METHODS: Normal Wistar rats were either administered with: a) vehicle only (control group), b) lipopolysaccharide only (LPS: 15 mg/kg) and then sacrificed at different time points (1 h, 3 h, 6 h and 10 h), and c) the last group was co-administered with LPS and ETDB (SB-209670, 1 mg/kg body weight) for 6 h and then sacrificed. KEY FINDINGS: Administration of LPS resulted in increases in levels of: a) serum tumor necrosis factor (TNF)-α, b) serum VEGF and c) serum endothelin (ET)-1 levels accompanied by up-regulation of cardiac VEGF and its downstream angiogenic signaling molecules. While cardiac TNF-α level was unchanged among experimental groups, cardiac ET-1 level was significantly higher in LPS-administered group. SIGNIFICANCE: We conclude that elevation in VEGF angiogenic signaling may be triggered by diminished oxygenation in the myocardium following LPS administration as a consequence of sepsis-induced microvascular dysfunction. Because of this cardiac dysfunction, oxygen supply may be inadequate at microregional level to support the normal heart metabolism and function. ETDB at 6 h further increased the elevated levels of VEGF angiogenic signaling in endotoxemic heart.

Vascular endothelial growth factor induces growth of uterine cervix and immune cell recruitment in mice.

Knowledge of uterine cervical epithelial biology and factors that influence its events may be critical in understanding the process of cervical remodeling (CR). Here, we examine the impact of exogenous vascular endothelial growth factor (VEGF) on uterine cervical epithelial growth in mice (nonpregnant and pregnant) treated with VEGF agents (recombinant and inhibitor) using a variety of morphological and molecular techniques. Exogenous VEGF altered various uterine cervical epithelial cellular events, including marked induction of growth, edema, increase in inter-epithelial paracellular space, and recruitment of immune cells to the outer surface of epithelial cells (cervical lumen). We conclude that VEGF induces multiple alterations in the uterine cervical epithelial tissues that may play a role in local immune surveillance and uterine cervical growth during CR.

Vascular endothelial growth factor induces mRNA expression of pro-inflammatory factors in the uterine cervix of mice.

Inflammation is believed to play a role in uterine cervical remodeling and infection-induced preterm labor. One of the distinct features of remodeling uterine cervix is presence of prominent vascular events, such as angiogenesis, vasodilation, and vascular permeability. Although the functional significance of these features is not yet clear, we know that in most tissue types, vascular remodeling is intricately intertwined with inflammation. Since vascular endothelial growth factor (VEGF) is the major architect of vascular remodeling, we sought to examine and elucidate the potential relationship between VEGF and inflammation in the uterine cervix of non-pregnant mice. The animals used were divided into 4 treatment groups: A) negative control (vehicle only), B) positive control (lipopolysaccharide, LPS), C) recombinant VEGF-164 protein, and D) LPS + VEGF blocker (n = 3). After the appropriate treatments, the uterine cervices were harvested and analyzed using real-time PCR and confocal fluorescence microscopy. Results showed that exogenous VEGF upregulates expression of interleukin (IL)-6 and tumor necrosis factor (TNF)-α mRNAs, whereas VEGF blocker partially diminishes the LPS-induced expression of pro-inflammatory factors compared to the positive control group. We conclude that a positive feed-forward relationship likely exists between VEGF and inflammation in the uterine cervix, thus implicating VEGF in inflammation-induced preterm labor.