Peptide mRNA Research Articles

Carotid baroreceptor stimulation improves cardiac performance and reverses ventricular remodelling in canines with pacing-induced heart failure

AimsCarotid baroreceptor stimulation (CBS) has potential protective effects on chronic heart failure (CHF). The aim of our study was to investigate the effects of CBS on more detailed aspects of ventricular remodelling and the underlying mechanisms in a CHF canine model. Main methodsTwenty-four beagles were randomised into Con (n = 8), CHF (n = 8), and CHF-CBS (n = 8) groups. The CHF and CHF-CBS groups underwent 6 weeks of rapid ventricular pacing (RVP) at 250 beats per minute to establish a CHF model. Concomitant CBS was delivered together with RVP in the CHF-CBS group. Key findingsRVP for 6 weeks caused typical heart failure in the CHF group. CBS significantly reversed the decrease in the high-frequency heart rate variability component and increase in low-frequency/high-frequency ratio induced by RVP. CBS significantly reduced cardiac dilation, improved left ventricle ejection fraction, and inhibited the increase in natriuretic peptide mRNA expression of LV tissue. CBS alleviated collagen volume fraction and reduced protein expression of transforming growth factor β1, matrix metallopeptidase 2, and matrix metallopeptidase 9, as well as decreased the percentage of TUNEL-positive nuclei and protein expression of Caspase-3 in LV tissue. The intracellular PKA signalling pathway and cardiac inflammation of LV tissue were upregulated in the CHF group, and markedly inhibited by CBS. SignificanceOur study found that CBS improved cardiac performance and reversed ventricular remodelling in CHF canines by rebalancing the autonomic nervous system; the suppression of the intracellular PKA signalling pathway and cardiac inflammation might underly the mechanisms.

Antigen-Specific TCR Signatures of Cytomegalovirus Infection.

CMV is a prevalent human pathogen. The virus cannot be eliminated from the body, but is kept in check by CMV-specific T cells. Patients with an insufficient T cell response, such as transplant recipients, are at high risk of developing CMV disease. However, the CMV-specific T cell repertoire is complex, and it is not yet clear which T cells protect best against virus reactivation and disease. In this study, we present a highly resolved characterization of CMV-specific human CD8+ T cells based on enrichment by specific peptide stimulation and mRNA sequencing of their TCR β-chains (TCRβ). Our analysis included recently identified T cell epitopes restricted through HLA-C, whose presentation is resistant to viral immunomodulation, and well-studied HLA-B-restricted epitopes. In eight healthy virus carriers, we identified a total of 1052 CMV-specific TCRβ sequences. HLA-C-restricted, CMV-specific TCRβ clonotypes dominated the ex vivo T cell response and contributed the highest-frequency clonotype of the entire repertoire in two of eight donors. We analyzed sharing and similarity of CMV-specific TCRβ sequences and identified 63 public or related sequences belonging to 17 public TCRβ families. In our cohort, and in an independent cohort of 352 donors, the cumulative frequency of these public TCRβ family members was a highly discriminatory indicator of carrying both CMV infection and the relevant HLA type. Based on these findings, we propose CMV-specific TCRβ signatures as a biomarker for an antiviral T cell response to identify patients in need of treatment and to guide future development of immunotherapy.

Hypothalamic mechanisms associated with corticotropin-releasing factor-induced anorexia in chicks

Central administration of corticotropin-releasing factor (CRF), a 41-amino acid peptide, is associated with potent anorexigenic effects in rodents and chickens. However, the mechanism underlying this effect remains unclear. Hence, the objective of the current study was to elucidate the hypothalamic mechanisms that mediate CRF-induced anorexia in 4 day-old Cobb-500 chicks. After intracerebroventricular (ICV) injection of 0.02 nmol of CRF, CRF-injected chicks ate less than vehicle chicks while no effect on water intake was observed at 30 min post-injection. In subsequent experiments, the hypothalamus samples were processed at 60 min post-injection. The CRF-injected chicks had more c-Fos immunoreactive cells in the arcuate nucleus (ARC), dorsomedial nucleus (DMN), ventromedial hypothalamus (VMH), and paraventricular nucleus (PVN) of the hypothalamus than vehicle-treated chicks. CRF injection was associated with decreased whole hypothalamic mRNA abundance of neuropeptide Y receptor sub-type 1 (NPYR1). In the ARC, CRF-injected chicks expressed more CRF and CRF receptor sub-type 2 (CRFR2) mRNA but less agouti-related peptide (AgRP), NPY, and NPYR1 mRNA than vehicle-injected chicks. CRF-treated chicks expressed greater amounts of CRFR2 and mesotocin mRNA than vehicle chicks in the PVN and VMH, respectively. In the DMN, CRF injection was associated with reduced NPYR1 mRNA. In conclusion, the results provide insights into understanding CRF-induced hypothalamic actions and suggest that the anorexigenic effect of CRF involves increased CRFR2-mediated signaling in the ARC and PVN that overrides the effects of NPY and other orexigenic factors.

High-fat diet accelerates extreme obesity with hyperphagia in female heterozygous Mecp2-null mice.

Rett syndrome (RTT) is an X-linked neurodevelopmental disorder caused by mutation of the methyl-CpG-binding protein 2 (MECP2) gene. Although RTT has been associated with obesity, the underlying mechanism has not yet been elucidated. In this study, female heterozygous Mecp2-null mice (Mecp2+/- mice), a model of RTT, were fed a normal chow diet or high-fat diet (HFD), and the changes in molecular signaling pathways were investigated. Specifically, we examined the expression of genes related to the hypothalamus and dopamine reward circuitry, which represent a central network of feeding behavior control. In particular, dopamine reward circuitry has been shown to regulate hedonic feeding behavior, and its disruption is associated with HFD-related changes in palatability. The Mecp2+/- mice that were fed the normal chow showed normal body weight and food consumption, whereas those fed the HFD showed extreme obesity with hyperphagia, an increase of body fat mass, glucose intolerance, and insulin resistance compared with wild-type mice fed the HFD (WT-HFD mice). The main cause of obesity in Mecp2+/--HFD mice was a remarkable increase in calorie intake, with no difference in oxygen consumption or locomotor activity. Agouti-related peptide mRNA and protein levels were increased, whereas proopiomelanocortin mRNA and protein levels were reduced in Mecp2+/--HFD mice with hyperleptinemia, which play an essential role in appetite and satiety in the hypothalamus. The conditioned place preference test revealed that Mecp2+/- mice preferred the HFD. Tyrosine hydroxylase and dopamine transporter mRNA levels in the ventral tegmental area, and dopamine receptor and dopamine- and cAMP-regulated phosphoprotein mRNA levels in the nucleus accumbens were significantly lower in Mecp2+/--HFD mice than those of WT-HFD mice. Thus, HFD feeding induced dysregulation of food intake in the hypothalamus and dopamine reward circuitry, and accelerated the development of extreme obesity associated with addiction-like eating behavior in Mecp2+/- mice.

EFFECTS OF NANOCURCUMIN IN RATS WITH DIABETES INDUCED WITH STREPTOZOTOCIN AND NICOTINAMIDE: MRNA EXPRESSION OF B-TYPE NATRIURETIC PEPTIDE

Objective: This study aimed to determine the effects of nanocurcumin on cardiomyopathy, assessed by the expression of B-type natriuretic peptide(BNP) mRNA in heart tissue.Methods: Type 2 diabetic rats were induced with streptozotocin and nicotinamide. Nanocurcumin was orally administered (100 mg/kg/day)for 30 days. BNP-45 mRNA expression in the heart tissue was measured using quantitative reverse transcription-polymerase chain reaction andcalculated using the Livak method.Results: BNP-45 levels increased significantly (p<0.05) in diabetic rats compared with the normal group. Nanocurcumin treatment at a dose of100 mg/kg for 30 days significantly decreased BNP-45 expression levels (p<0.05) compared with diabetic rats without treatment.Conclusion: Nanocurcumin may be beneficial in inhibiting the progression of diabetic cardiomyopathy by suppressing the expression of BNP-45.

Resistin promotes cardiac homing of mesenchymal stem cells and functional recovery after myocardial ischemia-reperfusion via the ERK1/2-MMP-9 pathway.

Stem cell therapy is a potentially effective and promising treatment for ischemic heart disease. Resistin, a type of adipokine, has been found to bind to adipose-derived mesenchymal stem cells (ADSCs). However, the effects of resistin on cardiac homing by ADSCs and on ADSC-mediated cardioprotective effects have not been investigated. ADSCs were obtained from enhanced green fluorescent protein transgenic mice. C57BL/6J mice were subjected to myocardial ischemia-reperfusion (I/R) or sham operations. Six hours after the I/R operation, mice were intravenously injected with resistin-treated ADSCs (ADSC-resistin) or vehicle-treated ADSCs (ADSC-vehicle). Cardiac homing by ADSCs and cardiomyocyte apoptosis were investigated 3 days after I/R. Cardiac function, fibrosis, and angiogenesis were evaluated 4 wk after I/R. Cellular and molecular mechanisms were investigated in vitro using cultured ADSCs. Both immunostaining and flow cytometric experiments showed that resistin treatment promoted ADSC myocardial homing 3 days after intravenous injection. Echocardiographic experiments showed that ADSC-resistin, but not ADSC-vehicle, significantly improved left ventricular ejection fraction. ADSC-resistin transplantation significantly mitigated I/R-induced fibrosis and reduced atrial natriuretic peptide/brain natriuretic peptide mRNA expression. In addition, cardiomyocyte apoptosis was reduced, whereas angiogenesis was increased by ADSC-resistin treatment. At the cellular level, resistin promoted ADSC proliferation and migration but did not affect H2O2-induced apoptosis. Molecular experiments identified the ERK1/2-matrix metalloproteinase-9 pathway as a key component mediating the effects of resistin on ADSC proliferation and migration. These results demonstrate that resistin can promote homing of injected ADSCs into damaged heart tissue and stimulate functional recovery, an effect mediated through the ERK1/2 signaling pathway and matrix metalloproteinase-9. NEW & NOTEWORTHY First, intravenous injection of adipose-derived mesenchymal stem cells (ADSCs) treated with resistin significantly increased angiogenesis and reduced myocardial apoptosis and fibrosis in a murine model of ischemia-reperfusion, resulting in improved cardiac performance. Second, resistin treatment significantly increased myocardial homing of intravenously delivered ADSCs. Finally, the ERK1/2-matrix metalloproteinase 9 pathway contributed to the higher proliferative and migratory capacities of ADSCs treated with resistin.

Airway infection with Nontypeable Haemophilus influenzae is more rapidly eradicated in vitamin D deficient mice

Chronic obstructive pulmonary disease (COPD), which is characterized by an excessive inflammatory response of the airways, is often complicated by exacerbations. Vitamin D deficiency has been associated with an increased risk for COPD and may predispose COPD patients to a higher exacerbation rate, particularly during smoking. In the current study, we investigated the effect of vitamin D deficiency and cigarette smoke (CS)-exposure on lung inflammation and bacterial clearance after an acute infection with Nontypeable Haemophilus influenzae (NTHi). Vitamin D deficient or sufficient mice were exposed to nose-only CS or ambient air for 6 weeks and oropharyngeally instilled with 106 NTHi. Residual viable NTHi were measured at different time points post-infection. Mechanisms of bacterial clearance (e.g. phagocytosis, pattern recognition receptors, antimicrobial peptides, surfactant proteins and mucin) and lung remodeling (e.g. metalloproteinases, MMP’s) were assessed. Although smoking resulted in reduced phagocytosis capacity of macrophages and neutrophils, bacterial clearance was similar to control mice. By contrast and independent of smoking, bacterial clearance was significantly accelerated in vitamin D deficient mice already from 24 h post-infection (p = 0.0087). This faster and complete eradication was associated with a more rapid resolution of cytokines and neutrophils 72 h post-infection and dominated by an upregulation of cathelicidin-related antimicrobial peptide (CRAMP) mRNA during infection (p = 0.026). However, vitamin D deficiency also resulted in more MMP12 protein in broncho-alveolar lavage and a shift in mRNA expression of MMP12/TIMP1 (p = 0.038) and MMP9/TIMP1 (p = 0.024) ratio towards more protease activity. Overall, vitamin D deficient mice resolved NTHi infection faster with a faster resolution of local lung inflammation, possibly through upregulation of CRAMP. This was associated with a disruption of the protease/anti-protease balance, which may potentially scale towards a higher extracellular matrix breakdown.

Decreased progranulin expression in Mycosis fungoides: a possible association with the high frequency of skin infections.

Progranulin (PGRN) is a multi-functional protein known to be involved in diverse biological processes, including tumourigenesis, anti-inflammation, and anti-infection. PGRN expression in sera or tissues is elevated in a variety of malignancies and is associated with poor prognosis. However, it remains to be determined whether PGRN is involved in Mycosis fungoides (MF). To investigate the roles of PGRN in MF. Serum PGRN levels were measured in patients with MF and normal controls by enzyme-linked immunosorbent assay. PGRN expression in MF and normal skin was examined by quantitative reverse transcription polymerase chain reaction and immunohistochemistry. Moreover, we analysed correlations between the expression levels of PGRN and antimicrobial peptides in lesional skin. PGRN levels were significantly lower in sera of MF patients than those of normal controls. PGRN mRNA levels in lesional skin of MF were also significantly decreased. Immunohistochemical staining revealed that PGRN was expressed in epidermal keratinocytes of normal controls, however, PGRN expression in epidermal keratinocytes was also weaker in MF skin. Furthermore, significant inverse correlations were identified between PGRN and antimicrobial peptide mRNA expression. These results suggest that low PGRN expression may contribute to the frequent occurrence of skin infections in patients with MF.

Hypothalamic PDE3B deficiency alters body weight and glucose homeostasis in mouse

Pharmacological studies have suggested hypothalamic phosphodiesterase-3B to mediate leptin and insulin action in regulation of energy homeostasis. Whereas Pde3b-null mice show altered energy homeostasis, it is unknown whether this is due to ablation of Pde3b in the hypothalamus. Thus, to address the functional significance of hypothalamic phosphodiesterase-3B, we used Pde3bflox/flox and Nkx2.1-Cre mice to generate Pde3b Nkx2.1KD mice that showed 50% reduction of phosphodiesterase-3B in the hypothalamus. To determine the effect of partial ablation of phosphodiesterase-3B in the hypothalamus on energy and glucose homeostasis, males and females were subjected to either a low- or high-fat diet for 19–21 weeks. Only female but not male Pde3b Nkx2.1KD mice on the low-fat diet showed increased body weight from 13 weeks onward with increased food intake, decreased fat pad weights and hypoleptinemia. Glucose tolerance was improved in high-fat diet-fed male Pde3b Nkx2.1KD mice in association with decreased phosphoenolpyruvate carboxykinase-1 and glucose-6-phosphatase mRNA levels in the liver. Also, insulin sensitivity was increased in male Pde3b Nkx2.1KD mice on the low-fat diet. Changes in body weight or in glucose homeostasis were not associated with any alteration in hypothalamic proopiomelanocortin, neuropepide Y and agouti-related peptide mRNA levels. These results suggest that partial loss of phosphodiesterase-3B in the hypothalamus produces a sex-specific response in body weight and glucose homeostasis, and support a role, at least in part, for hypothalamic phosphodiesterase-3B in regulation of energy and glucose homeostasis in mice.

Prepartum fatty acid supplementation in sheep. III. Effect of eicosapentaenoic acid and docosahexaenoic acid during finishing on performance, hypothalamus gene expression, and muscle fatty acids composition in lambs.

The objectives of this study were to evaluate the effect of feeding an enriched diet with eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA) to finishing lambs born from ewes supplemented either with or without EPA and DHA during late gestation on productive performance, muscle fatty acid (FA), and hypothalamus mRNA concentration of metabolic genes and hormone receptors. Lambs born from dams fed during the last 50 d of gestation either with a control diet containing 0.39% Ca salts of palmitic fatty acid distillate (C) or Ca salts enriched with EPA and DHA (PFA) were used. After weaning lambs (n = 70) were blocked by weight (BW) and used in a 2 × 2 factorial into 2 finishing diets containing 1.5% of C or PFA. The 2 factors were the ewe diet and the finishing diet. Lambs (37.9 ± 0.4 kg) were weighed and blood sampled for glucose and NEFA measurements at days 1, 14, 28, and 42. Dry matter intake (DMI) was measured daily. At day 43, 14 females and 14 males were slaughtered, and hot carcass weight, body wall thickness, rib eye area, and FA composition of Longissumus thoracis muscle were evaluated. Female hypothalamuses were obtained and mRNA concentration of hormone receptors, neuropeptides, and their receptors was measured. Lambs born from PFA dams were heavier (P < 0.01). There was a time × finishing diet interaction for BW (P = 0.03), and lambs fed C had a greater BW. Lambs fed C had an increase in DMI (P < 0.01). There were no significant differences in plasma glucose and NEFA concentration (P > 0.1). Lambs born from PFA dams had a greater concentration of C22:0 (P < 0.03). Lambs fed C had higher concentrations of C18:1c15 (P < 0.01), C17:0 (P < 0.09), C18:0 (P < 0.09), and n6/n3 (P < 0.01). Lambs fed PFA had greater concentration (P < 0.05) of C16:1, C22:1, C20:5, C22:5, C22:6, total n3 FA, and total EPA and DHA. There was a significant dam × finishing diet interaction (P ≤ 0.08) on mRNA concentration for MCR3, CCK-R, Cort-R, and CART. Lambs, which had the same treatment as their dams, showed lower overall mRNA concentration than those with different treatments between them and their dams. Lambs born from PFA ewes had lower concentration of MCR4 mRNA (P = 0.09) than C. Agouti-related peptides mRNA concentration was lower in lambs fed PFA (P = 0.06) than C. In conclusion, changes on lamb performance, muscle fatty acid composition, and metabolic neuropeptides depend not only on the lamb diet, but also on the dam diet during late gestation.

Dihydromyricetin Attenuates Myocardial Hypertrophy Induced by Transverse Aortic Constriction via Oxidative Stress Inhibition and SIRT3 Pathway Enhancement.

Dihydromyricetin (DMY), one of the flavonoids in vine tea, exerts several pharmacological actions. However, it is not clear whether DMY has a protective effect on pressure overload-induced myocardial hypertrophy. In the present study, male C57BL/6 mice aging 8–10 weeks were subjected to transverse aortic constriction (TAC) surgery after 2 weeks of DMY (250 mg/kg/day) intragastric administration. DMY was given for another 2 weeks after surgery. Blood pressure, myocardial structure, cardiomyocyte cross-sectional area, cardiac function, and cardiac index were observed. The level of oxidative stress in the myocardium was assessed with dihydroethidium staining. Our results showed that DMY had no significant effect on the blood pressure. DMY decreased inter ventricular septum and left ventricular posterior wall thickness, relative wall thickness, cardiomyocyte cross-sectional areas, as well as cardiac index after TAC. DMY pretreatment also significantly reduced arterial natriuretic peptide (ANP), brain natriuretic peptide (BNP) mRNA and protein expressions, decreased reactive oxygen species production and malondialdehyde (MDA) level, while increased total antioxidant capacity (T-AOC), activity of superoxide dismutase (SOD), expression of sirtuin 3 (SIRT3), forkhead-box-protein 3a (FOXO3a) and SOD2, and SIRT3 activity in the myocardium of mice after TAC. Taken together, DMY ameliorated TAC induced myocardial hypertrophy in mice related to oxidative stress inhibition and SIRT3 pathway enhancement.

Pseudomonas aeruginosa flagellum is critical for invasion, cutaneous persistence and induction of inflammatory response of skin epidermis

ABSTRACT Pseudomonas aeruginosa, an opportunistic pathogen involved in skin and lung diseases, possesses numerous virulence factors, including type 2 and 3 secretion systems (T2SS and T3SS) and its flagellum, whose functions remain poorly known during cutaneous infection. Using isogenic mutants deleted from genes encoding each or all of these three virulence factors, we investigated their role in induction of inflammatory response and in tissue invasiveness in human primary keratinocytes and reconstructed epidermis. Our results showed that flagellum, but not T2SS and T3SS, is involved in induction of a large panel of cytokine, chemokine, and antimicrobial peptide (AMP) mRNA in the infected keratinocytes. Chemokine secretion and AMP tissular production were also dependent on the presence of the bacterial flagellum. This pro-inflammatory effect was significantly reduced in keratinocytes infected in presence of anti-toll-like receptor 5 (TLR5) neutralizing antibody. Bacterial invasion of human epidermis and persistence in a mouse model of sub-cutaneous infection were dependent on the P. aeruginosa flagellum. We demonstrated that flagellum constitutes the main virulence factor of P. aeruginosa involved not only in early induction of the epidermis inflammatory response but also in bacterial invasion and cutaneous persistence. P. aeruginosa is mainly sensed by TLR5 during the early innate immune response of human primary keratinocytes.

Effects of toceranib compared with sorafenib on monocrotaline-induced pulmonary arterial hypertension and cardiopulmonary remodeling in rats

Sorafenib reverses pulmonary arterial hypertension (PAH) and cardiopulmonary remodeling (CPR), but the effects of toceranib are unknown. This study investigated anti-remodeling effects and determined optimal doses of toceranib and sorafenib on monocrotaline (MCT)-induced PAH and CPR in rats. MCT-treated rats were orally treated with a 14-day course of sorafenib (10, 30, or 100 mg/kg), toceranib (1, 3, or 10 mg/kg), or water. Both sorafenib and toceranib significantly reversed the right ventricular (RV) hypertrophy at 10 mg/kg, but only sorafenib significantly improved the RV systolic and mean pressures. Sorafenib significantly normalized the B-type natriuretic peptide mRNA level of the RV and increased the non-muscularized pulmonary artery percentage. However, these effects were only observed at the highest toceranib dose, and neither toceranib dose reduced the fully muscularized pulmonary artery percentage. Further, the inhibition on vascular endothelial growth factor (VEGF) signaling was stronger in sorafenib than in toceranib. Besides the stronger inhibition on mitogen-activated protein kinase signaling, the greater reversal ability of sorafenib may be also due to the simultaneous blockade on the C-X-C chemokine receptor type 4 and autophagy induction. Toceranib insignificantly reversed CPR, and a high-dose therapy did not improve the RV hemodynamic outcomes. Sorafenib significantly reversed CPR, and a low-dose sorafenib therapy may be a suitable therapeutic agent for PAH.

Hepcidin levels correlate to liver iron content, but not steatohepatitis, in non-alcoholic fatty liver disease

BackgroundOne-third of patients with non-alcoholic fatty liver disease (NAFLD) develop dysmetabolic iron overload syndrome (DIOS), the pathogenesis of which is unknown. Altered production of the iron-regulatory peptide hepcidin has been reported in NAFLD, but it is unclear if this is related to iron accumulation, lipid status or steatohepatitis.MethodsEighty-four patients with liver disease, 54 of which had iron overload, underwent liver biopsy (n = 66) and/or magnetic resonance imaging (n = 35) for liver iron content determination. Thirty-eight of the patients had NAFLD, 29 had chronic liver disease other than NAFLD, and 17 had untreated genetic hemochromatosis. Serum hepcidin was measured with ELISA in all patients and in 34 controls. Hepcidin antimicrobial peptide (HAMP) mRNA in liver tissue was determined with real-time-quantitative PCR in 36 patients.ResultsSerum hepcidin was increased similarly in NAFLD with DIOS as in the other chronic liver diseases with iron overload, except for genetic hemochromatosis. HAMP mRNA in liver tissue, and serum hepcidin, both correlated to liver iron content in NAFLD patients (r2 = 0.45, p < 0.05 and r2 = 0.27, p < 0.05 respectively) but not to body mass index, NAFLD activity score or serum lipids. There was a good correlation between HAMP mRNA in liver tissue and serum hepcidin (r2 = 0.39, p < 0.01).ConclusionsIn NAFLD with or without dysmetabolic iron overload, serum hepcidin and HAMP mRNA in liver correlate to body iron content but not to the degree of steatohepatitis or lipid status. Thus, the dysmetabolic iron overload syndrome seen in NAFLD is not caused by an altered hepcidin synthesis.

442 Effect of Fetal Programming and Finishing FA Supplementation on Hypothalamus mRNA Concentration.

Maternal nutrition produces metabolic and endocrine changes that may cause fetal programming effects. The objective of this study was to evaluate the effect of feeding an enriched diet with eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA) to ewes during late gestation and its effect to their offspring on the hypothalamus gene expression of hormones, metabolites and neurotransmitter receptors in finishing lambs. Lambs born from ewes fed during the last 50 days of gestation, either with a diet containing 0.39 % Ca salts of a palmitic fatty acid distillate (PFAD) or Ca salts enriched with EPA and DHA (PUFA) were used in this study. At lambing all ewes and lambs were penned together and fed the same pasture until weaning. After weaning the lambs were blocked by BW and divided in a 2x2 factorial into 2 finishing diet containing 1.5% of PFAD or PUFA. The 2 factors were the ewe diet and the finishing diet. On d 43, 14 female hypothalamuses were obtained and 18 metabolic genes were analyzed. There was a significant mother/treatment interaction in melanocortin receptor (MCR) 3 and cholecystokinin receptor (CCK-R) mRNA (P<0.01), and a tendency in cortisol receptor (Cor-R; P=0.06) and cocaine and amphetamine regulated protein (CART; P=0.08) mRNA; animals which had the same treatment as their mothers showed lower concentration than those with different treatment from their mother. Lambs born from PUFA ewes had lower concentration of MCR-4 mRNA showing a tendency (P=0.09) than PFDA. Agouti related peptides (AGRP) mRNA concentration was lower in lambs fed with PUFA (P=0.06) (Table 1) than PFDA. None of the other genes analyzed (insulin receptor, NPY and its receptors and POMC) had significant differences (P>0.1). Fatty acids change the expression of neuropeptides and their receptors and hormones receptors mRNA in the hypothalamus. Animals fed finishing diets with fatty acids that were opposite of the fatty acids in their dam’s diet during late gestation showed higher levels of mRNA than those with the same fatty acids in their diet. Table 1. Hypothalamic mRNA concentration in lambs fed with PUFA or PFAD and born from ewes with the similar FA supplementation. Table 1. Hypothalamic mRNA concentration in lambs fed with PUFA or PFAD and born from ewes with the similar FA supplementation.

Na+/H+ exchanger isoform 1-induced osteopontin expression facilitates cardiac hypertrophy through p90 ribosomal S6 kinase.

Cardiovascular diseases are the leading cause of death worldwide. One in three cases of heart failure is due to dilated cardiomyopathy. The Na+/H+ exchanger isoform 1 (NHE1), a multifunctional protein and the key pH regulator in the heart, has been demonstrated to be increased in this condition. We have previously demonstrated that elevated NHE1 activity induced cardiac hypertrophy in vivo. Furthermore, the overexpression of active NHE1 elicited modulation of gene expression in cardiomyocytes including an upregulation of myocardial osteopontin (OPN) expression. To determine the role of OPN in inducing NHE1-mediated cardiomyocyte hypertrophy, double transgenic mice expressing active NHE1 and OPN knockout were generated and assessed by echocardiography and the cardiac phenotype. Our studies showed that hearts expressing active NHE1 exhibited cardiac remodeling indicated by increased systolic and diastolic left ventricular internal diameter and increased ventricular volume. Moreover, these hearts demonstrated impaired function with decreased fractional shortening and ejection fraction. Atrial natriuretic peptide (ANP) and brain natriuretic peptide (BNP) mRNA was upregulated, and there was an increase in heart cell cross-sectional area confirming the cardiac hypertrophic effect. Moreover, NHE1 transgenic mice also showed increased collagen deposition, upregulation of CD44 and phosphorylation of p90 ribosomal s6 kinase (RSK), effects that were regressed in OPN knockout mice. In conclusion, we developed an interesting comparative model of active NHE1 transgenic mouse lines which express a dilated hypertrophic phenotype expressing CD44 and phosphorylated RSK, effects which were regressed in absence of OPN.

Interleukin-6/Stat3 signaling has an essential role in the host antimicrobial response to urinary tract infection

The signaling networks regulating antimicrobial activity during urinary tract infection (UTI) are incompletely understood. Interleukin-6 (IL-6) levels increase with UTI severity, but the specific contributions of IL-6 to host immunity against bacterial uropathogens are unknown. To clarify this we tested whether IL-6 activates the Stat3 transcription factor, to drive a program of antimicrobial peptide gene expression in infected urothelium during UTI. Transurethral inoculation of uropathogenic Escherichia coli led to IL-6 secretion, urothelial Stat3 phosphorylation, and activation of antimicrobial peptide transcription, in a Toll-like receptor 4-dependent manner in a murine model of cystitis. Recombinant IL-6 elicited Stat3 phosphorylation in primary urothelial cells invitro, and systemic IL-6 administration promoted urothelial Stat3 phosphorylation and antimicrobial peptide expression invivo. IL-6 deficiency led to decreased urothelial Stat3 phosphorylation and antimicrobial peptide mRNA expression following UTI, a finding mirrored by conditional Stat3 deletion. Deficiency in IL-6 or Stat3 was associated with increased formation of intracellular bacterial communities, and exogenous IL-6 reversed this phenotype in IL-6 knockout mice. Moreover, chronic IL-6 depletion led to increased renal bacterial burden and severe pyelonephritis in C3H/HeOuJ mice. Thus, IL-6/Stat3 signaling drives a transcriptional program of antimicrobial gene expression in infected urothelium, with key roles in limiting epithelial invasion and ascending infection.

Impaired intestinal immune barrier and physical barrier function by phosphorus deficiency: Regulation of TOR, NF-κB, MLCK, JNK and Nrf2 signalling in grass carp (Ctenopharyngodon idella) after infection with Aeromonas hydrophila

In aquaculture, the occurrence of enteritis has increased and dietary nutrition is considered as one of the major strategies to solve this problem. In the present study, we assume that dietary phosphorus might enhance intestinal immune barrier and physical barrier function to reduce the occurrence of enteritis in fish. To test this assumption, a total of 540 grass carp (Ctenopharyngodon idella) were investigated by feeding graded levels of available phosphorus (0.95–8.75 g/kg diet) and then infection with Aeromonas hydrophila. The results firstly showed that phosphorus deficiency decreased the ability to combat enteritis, which might be related to the impairment of intestinal immune barrier and physical barrier function. Compared with optimal phosphorus level, phosphorus deficiency decreased fish intestinal antimicrobial substances activities or contents and down-regulated antimicrobial peptides mRNA levels leading to the impairment of intestinal immune response. Phosphorus deficiency down-regulated fish intestinal anti-inflammatory cytokines mRNA levels and up-regulated the mRNA levels of pro-inflammatory cytokines [except IL-1β and IL-12p35 in distal intestine (DI) and IL-12p40] causing aggravated of intestinal inflammatory responses, which might be related to the signalling molecules target of rapamycin and nuclear factor kappa B. In addition, phosphorus deficiency disturbed fish intestinal tight junction function and induced cell apoptosis as well as oxidative damage leading to impaired of fish intestinal physical barrier function, which might be partially associated with the signalling molecules myosin light chain kinase, c-Jun N-terminal protein kinase and NF-E2-related factor 2, respectively. Finally, based on the ability to combat enteritis, dietary available phosphorus requirement for grass carp (254.56–898.23 g) was estimated to be 4.68 g/kg diet.

Exogenous Hydrogen Sulfide Supplement Attenuates Isoproterenol-Induced Myocardial Hypertrophy in a Sirtuin 3-Dependent Manner.

Hydrogen sulfide (H2S) is a gasotransmitter with a variety of cardiovascular protective effects. Sirtuin 3 (SIRT3) is closely related to mitochondrial function and oxidative stress. We found that NaHS increased SIRT3 expression in the preventive effect on isoproterenol- (ISO-) induced myocardial hypertrophy. We further investigated whether exogenous H2S supplement improved ISO-induced myocardial hypertrophy in a SIRT3-dependent manner. 10-week-old male 129S1/SvImJ (WT) mice and SIRT3 knockout (KO) mice were intraperitoneally injected with NaHS (50 μmol/kg/d) for two weeks and then intraperitoneally injected with ISO (60 mg/kg/d) for another two weeks. In WT mice, NaHS significantly reduced the cardiac index of ISO-induced mice, decreased the cross-sectional area of cardiomyocytes, and inhibited the expressions of atrial natriuretic peptide (ANP) and brain natriuretic peptide (BNP) mRNA. The activity of total antioxidant capacity (T-AOC) and superoxide dismutase (SOD) in the myocardium was increased, but the level of malondialdehyde (MDA) was decreased. The fluorescence intensity of dihydroethidium staining for superoxide anion was attenuated. Optic atrophy 1 (OPA1) expression was upregulated, while dynamin-related protein 1 (DRP1) expression was downregulated. ERK, but not P38 and JNK, phosphorylation was downregulated. However, all above protective effects were unavailable in ISO-induced SIRT3 KO mice. Our present study suggested that exogenous H2S supplement inhibited ISO-induced cardiac hypertrophy depending on SIRT3, which might be associated with antioxidant stress.

Induction and antiviral activity of human β-defensin 3 in intestinal cells with picornavirus infection.

Antimicrobial peptides produced by epithelial and immune cells protect tissues from various infections. Whether enterovirus infection leads to stimulation of antimicrobial peptide expression is unknown. We examined antimicrobial peptide mRNA and protein production in HT-29 colon adenocarcinoma cells infected with picornaviruses. The antiviral activity of increased antimicrobial peptide production was evaluated by using a recombinant peptide and corresponding gene overexpression. Enterovirus infection enhanced both the mRNA expression and secretion of human β-defensin (hBD) 3 in intestinal epithelial cells but did not increase expression of human neutrophil peptide 1-3 (HNP 1-3), HNP4, human defensin 5 (HD5), HD6, hBD1, hBD2, and hBD5. The recombinant but not the intracellularly overexpressed hBD3 inhibited enterovirus (EV) 71, coxsackievirus A16 (CVA16), CVB5 and poliovirus 1 (PV1) infecting HT-29 cells. Our results suggest that enterovirus infection induces hBD3 production in human intestinal epithelial cells and that hBD3 can exert extracellular anti-enterovirus activity.