Mesenteric Tissue Research Articles

Antiobesity and Hepatoprotective Effects of Protein Hydrolysates Derived from Protaetia brevitarsis in an Obese Mouse Model.

Background Obesity induced by excessive nutrients can cause fatty liver and metabolic dysfunction, which leads to hepatic dysfunction and local/systemic inflammatory responses. Previously, we analyzed the antioxidant, antilipotoxicity, and anti-inflammatory effects of protein hydrolysates in vitro. The aim of the present study is to investigate the antiobesity and hepatoprotective effects of protein hydrolysates derived from Protaectia brevitas (PHPB) in an obese mouse model. Methods For this in vivo study, 40 mice were included and divided into four groups: (1) normal diet group, (2) high-fat-diet (ctrl(–)) group, (3) high-fat-diet and silymarin-treated (ctrl(+)) group, and (4) high-fat-diet and PHPB-treated group. After 6 weeks of treatment, body weight and the amount of daily food intake were observed. Moreover, the major organs and blood of animals were collected for the analysis of serum chemistry, histopathological examination, and obesity- and inflammation-related gene expressions. Results The body weight and the amount of daily food intake significantly decreased in the PHPB-treated group compared with those in the ctrl(–) group. The levels of serum ALT, AST, ALP, creatinine, blood urea nitrogen, glucose, bilirubin, total cholesterol, TG, low-density lipoprotein, IL-6, TNF-α, and IGF-1 significantly reduced in the PHPB-treated group, whereas the serum free fatty acid, albumin, high-density lipoprotein, and adiponectin concentrations increased. In the analysis of weight of the liver, kidney, lungs, spleen, and fat tissues (from epididymal, perirenal, and mesentery tissues), the PHPB-treated group showed decreased values compared with the ctrl(–) group. In the histopathological analysis, the PHPB-treated group showed significantly reduced macrovesicular fatty change and inflammatory cell infiltration in the liver, and the size of the adipocyte in the epididymis also significantly decreased. The obesity- and inflammation-related gene (IL-6, TNF-α, IGF-1, leptin, AP2/FABP4, AMPK-α2, β3AR, and PPAR-γ) expressions in the liver and epididymal adipose tissue were reduced in the PHPB-treated group. Conclusions Overall, the results of this study suggest that the protein hydrolysates that derived from Protaectia brevitas produce antiobesity and hepatoprotective effects via anti-inflammatory activities.

Isolation and characterization of peritoneal microvascular pericytes.

As a potential source of myofibroblasts, pericytes may play a role in human peritoneal fibrosis. The culture of primary vascular pericytes in animals has previously been reported, most of which are derived from cerebral and retinal microvasculature. Here, in the field of peritoneal dialysis, we describe a method to isolate and characterize mouse peritoneal microvascular pericytes. The mesenteric tissues of five mice were collected and digested by type II collagenase and type I DNase. After cell attachment, the culture fluid was replaced with pericyte‐conditioned medium. Pericytes with high purity (99.0%) could be isolated by enzymatic disaggregation combined with conditional culture and magnetic activated cell sorting. The primary cells were triangular or polygonal with protrusions, and confluent cell culture could be established in 3 days. The primary pericytes were positive for platelet‐derived growth factor receptor‐β, α‐smooth muscle actin, neuron‐glial antigen 2, and CD13. Moreover, they promoted formation of endothelial tubes, and pericyte–myofibroblast transition occurred after treatment with transforming growth factor‐β1. In summary, we describe here a reproducible isolation protocol for primary peritoneal pericytes, which may be a powerful tool for in vitro peritoneal fibrosis studies.

En bloc mesoesophageal esophagectomy through thoracoscopy combined with laparoscopy based on the mesoesophageal theory.

To investigate the effectiveness and clinical significance of thoracolaparoscopic esophagectomy with mesoesophagus excision. Patients who underwent en bloc mesoesophageal esophagectomy through thoracoscopy combined with laparoscopy were retrospectively enrolled. Carbon nanoparticles were used in some patients to label the esophageal drainage lymph nodes. The clinical data were analyzed. En bloc mesoesophageal esophagectomy was successfully performed in 135 patients (100%). The carbon nanoparticles were used in 10 patients, among which the left gastric arterial lymph nodes were labeled in all patients and excised together with the left gastric mesentery, mesoesophagus, esophageal cancer, lymph nodes, vessels, nerves, and adipose tissues as one intact package. The mean operation time was 182.5 ± 26.4min, intraoperative blood loss 45.9 ± 17.6ml, mean number of lymph nodes dissected 20.9 ± 8.12, extubation time of drainage tubes 7.5 ± 3.8days, first oral feeding time 7.5 ± 1.8days, and postoperative hospital stay 13 ± 5.11days. Postoperatively, anastomotic leakage occurred in six patients (4.4%), anastomotic stenosis in eight (5.9%), hoarseness in seven (5.2%), and inflammation of the remnant stomach in four (3.0%), with a complication rate of 18.5%. Patients were followed up for 13-34months (median 23). Eighteen patients presented with organ metastasis. No local recurrence or death during follow-up. Based on the membrane anatomy or mesoesophagus theory, thoracolaparoscopic en bloc mesoesophageal esophagectomy is safe, with decreased blood loss, and it is necessary to resect the left gastric artery lymph nodes together with the left gastric mesentery and its contents to completely remove the cancer.

Effects of E scherichia coli Nissle 1917 on the Porcine Gut Microbiota, Intestinal Epithelium and Immune System in Early Life.

Early in life and particularly around weaning, piglets are susceptible to infections because of abrupt social, environmental, and dietary changes. Dietary interventions with probiotic bacteria have gained popularity because of the increased awareness of the direct link between diet and health. In this study, piglets received the probiotic strain Escherichia coli Nissle 1917 (EcN) or a control treatment perorally from day 2 after birth until 2 weeks post-weaning. To investigate spatio-temporal effects of EcN on the gut microbiota composition, intestinal epithelial gene expression and immune system, feces, digesta, blood, scraping material and mesenteric lymph node tissue were collected at different time points. In addition, oral vaccinations against Salmonella enterica serovar Typhimurium were administered on days 21 and 45 of the study to assess the immunocompetence. EcN-treated pigs showed a reduced diversity of taxa within the phylum Proteobacteria and a lower relative abundance of taxa within the genus Treponema during the pre-weaning period. Moreover, EcN induced T cell proliferation and Natural Killer cell activation in blood and enhanced IL-10 production in ex vivo stimulated mesenteric lymph node cells, the latter pointing toward a more regulatory or anti-inflammatory state of the local gut-associated immune system. These outcomes were primarily observed pre-weaning. No significant differences were observed between the treatment groups with regards to body weight, epithelial gene expression, and immune response upon vaccination. Differences observed during the post-weaning period between the treatment groups were modest. Overall, this study demonstrates that the pre-weaning period offers a ‘window of opportunity’ to modulate the porcine gut microbiota and immune system through dietary interventions such as EcN supplementation.

Influenza A Virus Causes Histopathological Changes and Impairment in Functional Activity of Blood Vessels in Different Vascular Beds.

It has been established that blood vessels are a target for influenza virus; however, the mechanism by which virus affects the cardiovascular system remains unknown. The aim of the study is the identification of histological changes and changes in the functional activity of the pulmonary and mesenteric blood vessels of Wistar rats. Wistar rats were intranasally infected with the influenza A(H1N1)pdm09 virus. At 24 and 96 h post infection (hpi), histopathological changes were observed in lung tissues with the absence of histological changes in mesenteric tissues. The functional activity of pulmonary and mesenteric arteries was determined using wire myography. In pulmonary arteries, there was a tendency towards an increase in integral response to the vasodilator and a decrease in the integral response to the vasoconstrictor at 24 hpi (compared with control). At 96 hpi, a tendency towards a decrease in the integral response to the vasoconstrictor persisted, while the response to acetylcholine was slightly increased. The functional activity of the mesenteric blood vessels was inverted: a significant decrease in the integral response to the vasodilator and an increase in the response to the vasoconstrictor at 24 hpi were observed; at 96 hpi, the integral response to the vasoconstrictor persisted, while the response to the vasodilator remained significantly reduced. Obtained data indicate the development of endothelial dysfunction in non-lethal and clinically non-severe experimental influenza virus infection.

An Ex Vivo Tissue Culture Method for Discovering Cell Dynamics Involved in Stromal Vascular Fraction Vasculogenesis Using the Mouse Mesentery.

Stromal vascular fraction (SVF), isolated from adipose tissue, identifies as a rich cell source comprised of endothelial cells, endothelial progenitor cells, pericytes, smooth muscle cells, fibroblasts, and immune cells. SVF represents a promising therapeutic heterogonous cell source for growing new blood microvessels due to its rich niche of cells. However, the spatiotemporal dynamics of SVF within living tissues remain largely unknown. The objective of this chapter is to describe a protocol for culturing SVF on mouse mesentery tissues in order to aid in the discovery of SVF dynamics and associated vessel growth over time. SVF was isolated from the inguinal adipose from adult mice and seeded onto mesentery tissues. Tissues were then cultured for up to 5days and labeled with endothelial cell and pericyte markers. Representative results demonstrate the observation of SVF-derived vasculogenesis characterized by de novo vessel formation and subsequent vessel connection.

The role of dendritic cells in the immune niche of the peritoneum.

Dendritic cells (DCs) are professional antigen presenting cells that play an important role in the induction of T cell responses. Different subsets (cDC1s, cDC2s, pDCs, and moDCs) were described based on the expression of different surface markers and functions. In the context of peritoneum, DCs are also a key population cell orchestrating immune responses against pathogens, malignant cells and tissue-damage. Furthermore, they play an important role in the promotion of an anti-inflammatory microenvironment, which is necessary to maintain tolerance and adipocyte homeostasis. The aim of this review is to summarize the current knowledge of the functional and phenotypic features of peritoneal DCs and shed some light on the importance of these cells within this unique cavity and its associated components: the omentum, the mesentery and gut-associated lymphoid tissue (GALT).

Role of mesenteric component in Crohn's disease: A friend or foe?

Crohn’s disease (CD) is a complex and relapsing gastrointestinal disease with mesenteric alterations. The mesenteric neural, vascular, and endocrine systems actively take part in the gut dysbiosis-adaptive immunity-mesentery-body axis, and this axis has been proven to be bidirectional. The abnormalities of morphology and function of the mesenteric component are associated with intestinal inflammation and disease progress of CD via responses to afferent signals, neuropeptides, lymphatic drainage, adipokines, and functional cytokines. The hypertrophy of mesenteric adipose tissue plays important roles in the pathogenesis of CD by secreting large amounts of adipokines and representing a rich source of proinflammatory or profibrotic cytokines. The vascular alteration, including angiogenesis and lymphangiogenesis, is concomitant in the disease course of CD. Of note, the enlarged and obstructed lymphatic vessels, which have been described in CD patients, are likely related to the early onset submucosa edema and being a cause of CD. The function of mesenteric lymphatics is influenced by endocrine of mesenteric nerves and adipocytes. Meanwhile, the structure of the mesenteric lymphatic vessels in hypertrophic mesenteric adipose tissue is mispatterned and ruptured, which can lead to lymph leakage. Leaky lymph factors can in turn stimulate adipose tissue to proliferate and effectively elicit an immune response. The identification of the role of mesentery and the crosstalk between mesenteric tissues in intestinal inflammation may shed light on understanding the underlying mechanism of CD and help explore new therapeutic targets.

Telmisartan relieves liver fibrosis and portal hypertension by improving vascular remodeling and sinusoidal dysfunction

BackgroundsTelmisartan(TEL) has demonstrated anti-fibrotic and blood pressure lowering effect in various diseases. In this study, we aimed to explore the beneficial effects of TEL on portal hypertension(PHT). MethodsTwo models of cirrhosis-induced PHT were involved including carbon tetrachloride injection(CCl4) and bile duct ligation(BDL). Rats were orally gavaged with TEL for 4 weeks. After that, the portal pressure(PP) was determined, and liver and mesenteric tissue specimens were collected to evaluate inflammatory response, liver fibrosis, vascular remodeling, angiogenesis, etc. ResultsIn CCl4 PHT models, TEL decreased PP significantly from 12.79 ± 2.92 to 6.91 ± 1.19 mmHg(p < 0.05). In inflammatory response, hepatic expressions of interleukin(IL)-6, lipopolysaccharide(LPS), and tumor necrosis factor-α(TNF-α) were significantly decreased after TEL treatment. Moreover, in the liver fibrotic area, the expressions of α-smooth muscle actin(α-SMA), collagen1a1(Col1a1), desmin, transforming growth factor-β(TGF-β), and hydroxyproline, and serum hyaluronic acid were significantly decreased after TEL treatment. Additionally, the expressions of von Willebrand factor(vWF), vascular endothelial growth factor(VEGF) and platelet-derived growth factor-β(PDGF-β), matrix metallopeptidase(MMP)-2, and MMP-9 were ameliorated in liver sinusoid, while the expressions of MMP-2 and vWF were reduced in mesenteric arteries after TEL treatment. Meanwhile, TEL treatment up-regulated the hepatic expressions of an anti-fibrotic factor Krüppel-like factor-4(KLF-4) and its downstream endothelial nitric oxide synthase(eNOS) in rats with PHT. The performance of TEL in BDL model was similar but slightly weaker. ConclusionsTEL ameliorated the cirrhosis-induced PHT by reducing liver fibrosis, inflammation responses, angiogenesis, and vascular remodeling. Collectively, KLF-4 and eNOS were the possible molecular targets for the management of cirrhosis-associated PHT.

LOW WEIGHT GAIN, BETTER GLYCAEMIA AND NO CENTRAL OBESITY ACHIEVED THROUGH A HIGH-PROTEIN DIET

A compendium of metabolic diseases associated with unhealthy habits plague the modern world today. Weight gain, hyperglycemia and excess adiposity are some of the metabolic diseases plaguing our modern society. Unhealthy dietary habits coupled with a sedentary lifestyle are recognized as important factors for the development of some metabolic illnesses. Cardiovascular diseases, diabetes mellitus, hypertension, and dyslipidemia were recognized as stemming from metabolic dysregulation due to the consumption of excess calories from certain macronutrients. Our objective in this study is to find out which diet most affects circulating blood glucose levels, body weight, and visceral fat tissue deposition. 35 male Sprague - Dawley rats were separated into five groups and were given five distinct diets for the duration of 8 weeks. The five diets are normal rat feed, high-fat, high-protein, high-sugar, and high-starch. The feeding provided was ad libitum with tap water given as drinking water. Every week, each rat was weighed, and blood were sampled for glucose. Post-sacrifice, mesenteric fat was harvested, fixed, and stained for histological analysis. The results revealed a high-protein diet significantly reduces body weight gain, improved blood sugar with no development of central obesity. At the same time, a high-fat diet was shown to be a promoter of mesenteric fat tissue hypertrophy. It was concluded that the consumption of a high-protein diet was found to achieve low weight gain, better glycaemia with no central obesity.

Development of an in vitro tissue culture system for hammer coral (Fimbriaphyllia ancora) ovaries

In vitro gonad culture systems have proven useful to investigate intrinsic mechanisms of sexual reproduction in animals. Here we describe development of an in vitro culture method for coral ovaries. Mesenterial tissues containing both ovaries and mesenterial filaments were microscopically isolated from the scleractinian coral, Fimbriaphyllia ancora, and culture conditions were optimized. M199 diluted 10× (10% M199, pH 8.1) and supplemented with 25 mM HEPES and the antibiotics, ampicillin, penicillin and streptomycin, supported oocyte survival and maintained the structural integrity of ovaries during short-term culture (~ 6 days). Addition of a commercial antibiotic–antimycotic solution (Anti–Anti) and fetal bovine serum adversely affected ovary maintenance and caused tissue disintegration. Characterization of cultured ovaries showed that there is no difference in cell proliferation of ovarian somatic cells between culture Days 1 and 6. Moreover, the presence of oogonia and expression of a major yolk protein, vitellogenin, were confirmed in ovaries cultured for 6 days. This system will be useful for studying effects of a wide range of substances on coral oogenesis.

The protective effect of Jangkanghwan (Korean traditional food) on lipopolysaccharide-induced disruption of the colonic epithelial barrier

Jangkanghwan (JKH) is a Korean traditional food that is a mixture of food ingredients and traditional Korean medicine ingredients, and it has been observed to produce satisfactory anti-inflammatory, antioxidant, and antibacterial effects. In the current study, JKH was administered by gavage to BALB/C mice with lipopolysaccharide (LPS)-induced colonic epithelial dysfunction, and mouse body weight and food intake were recorded. Indexes such as colonic paracellular permeability, serum inflammatory cytokines, and bacterial translocation were used to comprehensively evaluate the regulatory effect of JKH on mouse colonic epithelial function, and qPCR and Western blot were also used to analyze the expression of tight junction (TJ)-related genes, such as occludin, claudin, zonula occludens (ZOs) proteins, and junction adhesion molecules (JAM) in the colonic epithelial tissue. The experimental results indicated that JKH relieved the edema of the liver, spleen, and mesenteric lymph node tissues, and reduced the loss of appetite and diarrhea caused by LPS injection in mice. It increased the amount of mice food intake from 3.7 g/day in the LPS group to 4.7 g per day; the water content in the feces of mice in the JKH group was 13.86% less than that in the LPS group. JKH reduced the inflammatory response in mice caused by LPS, protected the integrity of the colon, the permeability of fluorescent macromolecules was one-fourth of the LPS group, and enhanced the mRNA and protein expression of TJ-related proteins in colon tissue. Our findings highlight that JKH has benefits in intestinal health and relieving systemic inflammation, relevant aspects of its use as a functional food.

Vitamin D deficiency attenuates endothelial function by reducing antioxidant activity and vascular eNOS expression in the rat microcirculation.

This study examined the effects of vitamin D deficiency on vascular function and tissue oxidative status in the microcirculation; and whether or not these effects can be ameliorated with calcitriol, the active vitamin D metabolite. Three groups (n=10 each) of male Sprague Dawley rats were fed for 10weeks with control diet (CR), vitamin D-deficient diet without (DR), or with oral calcitriol supplementation (0.15μg/kg) for the last four weeks (DSR). After 10weeks, rats were sacrificed; mesenteric arterial rings were studied using wire myograph. Oxidative stress biomarkers malondialdehyde (MDA) levels and superoxide dismutase (SOD) activity were measured in the mesenteric arterial tissue. Vascular protein expression of endothelial nitric oxide synthase (eNOS) was determined by Western blotting. Acetylcholine-induced endothelium-dependent relaxation of DR was lower than CR. eNOS expression and SOD activity were lower in mesenteric arterial tissue of DR compared to CR. Calcitriol supplementation to DSR did not ameliorate the above parameters; in fact, augmented endothelium-dependent contraction was observed. Serum calcium was higher in DSR compared to CR and DR. In conclusion, vitamin D deficiency impaired microvascular vasodilation, associated with eNOS downregulation and reduced antioxidant activity. Calcitriol supplementation to vitamin D-deficient rats at the dosage used augmented endothelium-dependent contraction, possibly due to hypercalcaemia.

S2972 Primary Squamous Cell Carcinoma of the Ileum - A Rare Entity

Introduction: The small intestine is the most common site for metastatic spread in the gastrointestinal tract. Squamous cell carcinoma (SCC) from a wide variety of sites can metastasize to the small intestine. Primary SCC of the small intestine are rare. We present a rare case of primary SCC of the ileum. Case Description/Methods: A 70-year-old male presented with complaints of abdominal pain for 5 days. Physical exam revealed tenderness on palpation on the right lower quadrant. Labs significant for WBC count of 13k/ul and lactic acid of 10.9 mmol/l. CT Abdomen revealed small bowel obstruction and suspected perforated mass within the ileum. (figure A). Mesenteric lymphadenopathy concerning for metastasis. Laparoscopy revealed an ileal perforation with a matted mass of the distal small intestine which was resected and ileocolonic anastomosis was performed. Gross exam revealed a 6.8*4.7cm ill-defined mass, irregular in appearance with tan pink and nodular texture with areas of necrosis. The mass was submucosal in location, extending to the adjacent mesenteric soft tissue. Histology revealed an invasive poorly differentiated SCC with perforation and invasion of the mesenteric lympho-vascular spaces (figure B). Neoplastic cells were positive for p40(figure C), p63(figure D), ck5/6 and pancytokeratin while negative for ck7, ck20, cdx2, ttf1, synaptophysin, chromogranin, cd45 and S100. The patient had a prolonged postoperative course with multi organ failure, was made palliative on postoperative day 14 and he expired on the same day. Discussion: Several mechanisms have been proposed for primary SCC of the small bowel. Some of which include submucosal squamous epithelium undergoing malignant transformation, aberrant transformation of stem cells into squamous cells with subsequent malignant change. It is difficult to differentiate between primary versus metastatic squamous cell carcinoma of the small bowel. In our patient, imaging studies, immune-histochemical staining and histology results points towards a primary SCC of the ileum. We believe that our patient had primary SCC of the terminal ileum without underlying adenoma, inflammatory disease, or duplication. Optimal treatment and the prognosis are unknown because of the rarity of this condition. Surgery is the mainstay in the management of the disease. Due to the small number of cases available in the literature, the effects of chemotherapy and radiotherapy on the survival and recurrence are unknown.Figure 1.: A CT abdomen axial view showing irregular configuration of a loop of small bowel with adjacent air bubbles suspicious for a perforated mass located within the ileum. B Histology demonstrating tumor nests, composed of large cells with hyperchromatic, pleomorphic nuclei and eosinophilic cytoplasm infiltrating the muscularis propria. Neoplasm is diffusely positive for P40 (C) and p63 (D)-indicating squamous cells

The Clinical Significance of Mesenteric Lymphocytes in Human Colorectal Cancer.

ObjectiveThe mesentery is a potential site of residual tumor in patients with colorectal cancer (CRC). However, the mesenteric immune microenvironment remains unclear. In this study, we investigated the immune landscape of the mesentery, particularly the role of lymphocytes and its association with the clinicopathological characteristics of CRC.MethodsFlow cytometry was used to detect lymphocytes in the paired mesenteric tissue specimens adjacent to the colorectal tumors and normal mesenteric tissue specimens 10 cm away from the colorectal tumor edge and preoperative peripheral blood samples obtained from patients with CRC who underwent surgery. T-distributed stochastic neighbor embedding was utilized to analyze multiparameter flow cytometry data. Multiplex immunohistochemistry was performed to evaluate T cells subsets in the paired mesentery adjacent to the colorectal tumors and normal mesentery. The Fisher’s exact test and non-parametric Wilcoxon’s matched-pairs tests were used for statistical analysis. The non-parametric Mann-Whitney U test was used to determine associations between percentage data and clinical parameters of patients with CRC.ResultsWe found that immune cells in the normal mesentery were mainly of lymphoid lineage. Compared with peripheral blood, the normal mesentery showed decreased NK cells and the CD4/CD8 ratio and increased CD3+ CD56+, memory CD4+ T, memory CD8+ T, CD4+ tissue-resident memory T (TRM), and CD8+ TRM cells. Compared with the normal mesentery, the mesentery adjacent to the colorectal tumor showed increased B and regulatory T cells and decreased NK, CD3+ CD56+, CD4+ TRM, and CD8+ TRM cells. Moreover, memory CD8+ T cells and plasmablasts are negatively correlated with the depth of invasion of CRC. Increased memory CD4+ T cells are associated with distant metastasis of CRC and high preoperative serum carcinoembryonic antigen levels.ConclusionThe mesentery shows a specific immune microenvironment, which differs from that observed in peripheral blood. CRC can alter the mesenteric immune response to promote tumor progression.

Assessment of Imaging Features of Crohn's Disease with MR Enterography.

To evaluate the frequency of pathological findings determined on magnetic resonance (MR) enterography (MRE) in patients with Crohn's Disease. A retrospective analysis of the MRE images was made in 34 female and 41 male patients (mean age 41 years) with Crohn's disease. The prevalence of bowel wall (mural thickening, mural edema, mural fat deposits, mucosal enhancement, ulceration, cobblestone appearance, pseudopolyps) and mesenteric fatty tissue alterations (fatty tissue proliferation, mesenteric hypervascularity, enlarged lymph nodes, peri-enteric inflammation, reactive fluid), complications due to penetrating (fistula, sinus tract, abscess) and stenosing processes (fibrotic and inflammatory stenosis, obstruction, dilatation), and involvement of the colon were determined. The most frequently observed changes in the bowel wall and mesenteric fatty tissue were mural thickening (98.7%) and enlargement of mesenteric lymph nodes (76%), respectively. Stenosis was the most common complication (76%). The most frequently seen pathology of the colon was ileocecal valve thickening and enhancement (74.7%). MR enterography is a useful imaging modality for the evaluation of changes in both the mesenteric fatty tissue and the bowel wall. As there is no use of ionizing radiation, MR enterography should be the preferred imaging modality during follow-up of patients with Crohn's disease.

Abstract MP26: Angiotensin-(1-7) Increases Vascular Beta-2 Adrenergic Receptor Expression In Aging Mice

Aging is associated with increased sympathetic tone, which desensitizes vascular beta-2 adrenergic receptors (B2AR) to impair vasodilation and promote hypertension. We recently demonstrated that chronic treatment with angiotensin (Ang)-(1-7), a protective hormone of the renin-angiotensin system, decreases blood pressure and cardiac sympathetic tone in aging mice. In this study, we hypothesized that sympathoinhibitory effects of Ang-(1-7) would restore vascular B2AR expression to lower blood pressure in aging. To test this, aging (16-month-old) and young (2-month-old) male C57BL/6J mice received Ang-(1-7) [400 ng/kg/min, n=4] or saline (n=4) infusion for 6 weeks via subcutaneous osmotic mini-pump. At end of treatment, alpha- and beta-adrenergic receptor gene expression was measured in mesenteric arteries, thoracic aorta, and cardiac tissue by quantitative real-time PCR and quantified with 2-ΔΔCT methods. In a separate experiment, male C57BL/6J mice received a single subcutaneous injection of Ang-(1-7) (2 mg/mg, n=4), saline (n=3), or the B2AR antagonist ICI 118,551 (1 mg/kg) plus Ang-(1-7) (n=3). Blood pressure was measured via a carotid artery catheter at baseline and post-treatment. We found that aging mice have decreased mesenteric B2AR gene expression, which was restored by Ang-(1-7) (young saline: 1.04±0.35; aged saline: 0.46±0.17; aged Ang-(1-7): 1.04±0.31 A.U., p=0.026). As a control, Ang-(1-7) did not induce significant changes in B2AR mRNA in thoracic aorta or cardiac tissue, or changes in other adrenergic receptor subtypes (alpha1 or beta1) in any of the tissues studied in aging mice (p&gt;0.05). We further found that depressor effects of acute Ang-(1-7) in mice are attenuated by B2AR blockade (saline: Δ -11±4 mmHg; Ang-(1-7): Δ -26±3 mmHg; ICI 118,551+Ang-(1-7): Δ -4±4 mmHg, p=0.009). Overall, these findings suggest that Ang-(1-7) restores B2AR expression in mesenteric resistance vessels in aging mice, and depressor effects of acute Ang-(1-7) are partially mediated by B2AR. These data support the concept that Ang-(1-7) decreases blood pressure in aging by restoring B2AR-mediated vasodilation. More broadly, Ang-(1-7) may provide a novel treatment target for age-related hypertension and cardiovascular disease.

Whole blood resuscitation restores intestinal perfusion and influences gut microbiome diversity.

Gut dysbiosis, an imbalance in the gut microbiome, occurs after trauma, which may be ameliorated with transfusion. We hypothesized that gut hypoperfusion following trauma causes dysbiosis and that whole blood (WB) resuscitation mitigates these effects. Anesthetized rats underwent sham (S; laparotomy only, n = 6); multiple injuries (T; laparotomy, liver and skeletal muscle crush injuries, and femur fracture, n = 5); multiple injuries and 40% hemorrhage (H; n = 7); and multiple injuries, hemorrhage, and WB resuscitation (R; n = 7), which was given as 20% estimated blood volume from donor rats 1 hour posttrauma. Baseline cecal mesenteric tissue oxygen (O2) concentration was measured following laparotomy and at 1 hour and 2 hours posttrauma. Fecal samples were collected preinjury and at euthanasia (2 hours). 16S rRNA sequencing was performed on purified DNA, and diversity and phylogeny were analyzed with QIIME (Knight Lab, La Jolla, CA; Caporaso Lab, Flagstaff, AZ) using the Greengenes 16S rRNA database (operational taxonomic units; 97% similarity). α and β diversities were estimated using observed species metrics. Permutational analysis of variance was performed for overall significance. In H rats, an average decline of 36% ± 3.6% was seen in the mesenteric O2 concentration at 1 hour without improvement by 2 hours postinjury, which was reversed following resuscitation at 2 hours postinjury (4.1% ± 3.1% difference from baseline). There was no change in tissue O2 concentration in the S or T rats. β Diversity differed among groups for all measured indices except Bray-Curtis, with the spatial median of the S and R rats more similar compared with S and H rats (p < 0.05). While there was no difference in α diversity found among the groups, indices were significantly correlated with mesenteric O2 concentration. Members of the family Enterobacteriaceae were significantly enriched in only 2 hours. Mesenteric perfusion after trauma and hemorrhage is restored with WB resuscitation, which influences β diversity of the gut microbiome. Whole blood resuscitation may also mitigate the effects of hemorrhage on intestinal dysbiosis, thereby influencing outcomes.

Significance of serum palmitoleic acid levels in inflammatory bowel disease

Inflammatory bowel diseases (IBDs), including ulcerative colitis (UC) and Crohn’s disease (CD), are chronic intestinal diseases of unknown etiology that present with variable disease extents and outcomes. The use of biomarkers for the diagnosis and management of IBDs is considered beneficial. Palmitoleic acid (PO) is an adipose tissue-derived mono-unsaturated free fatty acid that potentially serves as a lipokine in metabolic and inflammatory diseases. The aim of this study was to investigate the significance of PO levels in the serum of patients with UC and CD. The study included patients with UC (n = 22), patients with CD (n = 35), and controls (n = 22). The levels of serum PO were analyzed using gas chromatography. The association of serum PO levels with the clinical features and disease outcomes in IBD was examined. Serum PO levels were significantly higher in patients with CD than in controls, whereas no difference in these levels was observed between patients with UC and controls. Serum PO levels were significantly associated with the CD activity index. Additionally, high serum PO levels were associated with an increased risk of surgical intervention requirement during follow-up. In a pilot study with a few patients, high PO levels were observed in the mesenteric tissue in the active disease site of patients with CD (n = 7) compared with those with colon cancer (n = 6). Elevated serum PO levels might serve as a marker for local inflammation and prognosis in patients with CD.

Cutaneous desmoid‐type fibromatosis: A rare case with molecular profiling

Fibromatoses encompass a broad group of histopathologically similar fibroblastic/myofibroblastic proliferations with divergent clinical manifestations and behavior. Deep (desmoid-type) fibromatoses are typically large, rapidly growing, and locally aggressive tumors that occur in the abdominal wall, mesentery, and extra-abdominal soft tissue, principally the musculature of the trunk and extremities. Most sporadic cases of desmoid fibromatosis harbor inactivating mutations in CTNNB1, the gene encoding beta-catenin. Tumors occurring in the context of familial adenomatous polyposis and Gardner syndrome bear inactivating mutations in APC. By contrast, mutations in CTNNB1 or APC have not been identified in cases of superficial fibromatosis. Cutaneous involvement by desmoid fibromatosis is exceedingly rare. Here we present a 78-year-old male with desmoid-type fibromatosis arising in the dermis of the right medial calf with a pathogenic mutation in CTNNB1 and a variant of unknown significance in APC.