Calcium antagonist verapamil prevented pulmonary arterial hypertension in broilers with ascites by arresting pulmonary vascular remodeling

Effect of Qiling Jiaogulan Powder on Pulmonary Fibrosis and Pulmonary Arteriole Remodeling in Low-Temperature-Exposed Broilers

Chinese herbal medicine plays an important role in regulating the nutritional metabolism of poultry and maintaining or improving normal physiological functions and animal health. The present study investigated the effects of dietary supplementation with Qiling Jiaogulan Powder (QLJP) on pulmonary fibrosis and pulmonary arteriole remodeling in low temperature-exposed broilers. Seven-day-old Ross 308 broilers (n = 240) were reared adaptively to 14 days of age. The broilers were randomly divided into six groups: A control group (basal diet and normal feeding temperature); model group (basal diet); low-, medium- and high-dose QLJP groups (basal diet supplemented with 1 g/kg, 2 g/kg, 4 g/kg QLJP); and L-Arg group (basal diet supplemented with 10 g/kg L-arginine). Additionally, all the broilers, except the broilers in the control group, from the age of 14 days old, had a house temperature continuously lowered by 2 °C each day until it reached 12 °C at 21 days of age, and the low temperature was maintained until the end of the experiment. There were four replicates per group and 10 birds per replicate. The results showed that the structure of the lung tissue was clearer and basically intact in the broilers in the QLJP groups, with a small number of collagen fibers formed, and the content of hydroxyproline (HYP) was significantly reduced. QLJP improved pulmonary arteriole lesions, such as tunica media thickening, intimal hyperplasia, arterial wall hypertrophy, and lumen narrowing. QLJP reduced the relative media thickness (%) and relative medial area (%) of the pulmonary arteriole, and significantly decreased the expression level of the alpha-smooth muscle actin (α-SMA) protein in pulmonary arteriole, which alleviated pulmonary arteriole remodeling. The quantitative real-time PCR (qPCR) and enzyme-linked immunosorbent assay (ELISA) results showed that QLJP treatment significantly reduced the gene and protein levels of transforming growth factor-beta l (TGF-β1) and Smad2 in the lung and downregulated the gene and protein levels of collagen type I alpha 1 (COL1A1) and matrix metalloproteinase 2 (MMP2). In conclusion, the results of our study suggested that dietary supplementation with QLJP improved pulmonary fibrosis and pulmonary arteriole remodeling by inhibiting the expression of genes related to the TGF-β1/Smad2 signaling pathway and inhibited the occurrence and development of pulmonary arterial hypertension in low-temperature-exposed broilers.

Cardiovascular Diseases in Pet Birds: Therapeutic Options and Challenges

Cardiovascular disease, including congestive heart failure, pericardial disease, and atherosclerosis, is becoming increasingly better recognized in companion birds. A wide range of medications is available to treat these conditions, including diuretics, vasodilators, positive and negative inotropes, antiarrhythmic agents, and pentoxifylline. This review systematically discusses each of these drug classes and their potential applications in avian species. Although treatment approaches remain largely empirical and extrapolated from small animal and human medicine, the management strategies presented here have the potential to both maintain quality of life and extend survival time for the avian cardiac patient.

Aster tataricus alleviates constipation by antagonizing the binding of acetylcholine to muscarinic receptor and inhibiting Ca2+ influx

BACKGROUND

The dried root and rhizome of Aster tataricus (RA), is a traditional Chinese medicine has been used for more than 2000 years with the function of antitussive, expectorant and antiasthmatic. Ancient books and modern pharmacological researches demonstrated that RA may have the function of moistening intestines and relieving constipation, but there was a lack of systematic evidence. The aim of this study was to comprehensively evaluate the efficacy and possible mechanisms of ethanol extract of Aster tataricus (ATE) in treating constipation from in vivo to in vitro.

METHODS

In vivo, the ATE was studied in loperamide-induced constipation of mice. In vitro, different concentrations of ATE was tested separately or cumulatively on spontaneous and agonists-induced contractions of isolated rat duodenum strips.

RESULTS

In vivo, at doses of 0.16, 0.8 g/mL, ATE showed significantly promotion of the small intestinal charcoal transit, decrease of the amount of remnant fecal, and increase of the content of fecal water in colon. In addition, ATE could effectively relieve colonic pathological damage caused by loperamide as well. In vitro, with the cumulative concentration increase of ATE from 0.8 to 6.4 mg/mL, it could significantly decrease the contraction caused by KCl or Ach, and gradually restore to near base tension value.Meanwhile, it could also partially but significantly inhibit the contractions induced by Ach and CaCl2 on rat duodenum in a concentration related manner.

CONCLUSIONS

Taking all these findings together, it could be speculated that ATE may attenuate constipation mainly through antagonizing the binding of acetylcholine to muscarinic receptor, inhibiting Ca2+ influx and anti-inflammation.

Cardiovascular Drugs in Avian, Small Mammal, and Reptile Medicine

Cardiovascular disease, including congestive heart failure, pericardial disease, and atherosclerosis, is becoming increasingly better recognized in companion birds, small mammals, and reptiles. A wide range of medications is available to treat these conditions, including diuretics, vasodilators, positive and negative inotropes, antiarrhythmic agents, and pentoxifylline. This review systematically discusses each of these drug classes and their potential applications in exotic species. Although treatment approaches remain largely empirical and extrapolated from small animal and human medicine, the management strategies presented here have the potential to both maintain quality of life and extend survival time for the exotic cardiac patient.

Transcriptome Analysis and Gene Identification in the Pulmonary Artery of Broilers with Ascites Syndrome

BACKGROUND

Pulmonary arterial hypertension, also known as Ascites syndrome (AS), remains a clinically challenging disease with a large impact on both humans and broiler chickens. Pulmonary arterial remodeling presents a key step in the development of AS. The precise molecular mechanism of pulmonary artery remodeling regulating AS progression remains unclear.

METHODOLOGY/PRINCIPAL FINDINGS

We obtained pulmonary arteries from two positive AS and two normal broilers for RNA sequencing (RNA-seq) analysis and pathological observation. RNA-seq analysis revealed a total of 895 significantly differentially expressed genes (DEGs) with 437 up-regulated and 458 down-regulated genes, which were significantly enriched to 12 GO (Gene Ontology) terms and 4 KEGG (Kyoto Encyclopedia of Genes and Genomes) pathways (Padj<0.05) regulating pulmonary artery remodeling and consequently occurrence of AS. These GO terms and pathways include ribosome, Jak-STAT and NOD-like receptor signaling pathways which regulate pulmonary artery remodeling through vascular smooth cell proliferation, inflammation and vascular smooth cell proliferation together. Some notable DEGs within these pathways included downregulation of genes like RPL 5, 7, 8, 9, 14; upregulation of genes such as IL-6, K60, STAT3, STAT5 Pim1 and SOCS3; IKKα, IkB, P38, five cytokines IL-6, IL8, IL-1β, IL-18, and MIP-1β. Six important regulators of pulmonary artery vascular remodeling and construction like CYP1B1, ALDH7A1, MYLK, CAMK4, BMP7 and INOS were upregulated in the pulmonary artery of AS broilers. The pathology results showed that the pulmonary artery had remodeled and become thicker in the disease group.

CONCLUSIONS/SIGNIFICANCE

Our present data suggested some specific components of the complex molecular circuitry regulating pulmonary arterial remodeling underlying AS progression in broilers. We revealed some valuable candidate genes and pathways that involved in pulmonary artery remodeling further contributing to the AS progression.

An evaluation of vardenafil as a calcium channel blocker in pulmonary artery in rats

OBJECTIVE

Vardenafil was reported to relax rat pulmonary artery through endothelium-dependent mechanisms. The aim of this in vitro study was to investigate other related mechanisms for this effect.

MATERIALS AND METHODS

Endothelium-intact and denuded artery rings were suspended in order to record isometric tension. In the rings with or without endothelium, the concentration-response curves for vardenafil were generated. In the rings without endothelium the contractile response induced by phenylephrine (Phe) or KCl was assessed in the presence or absence of vardenafil. In the last set of experiments, pulmonary artery rings were exposed to calcium-free isotonic depolarizing solution and the contractile response induced by the addition of calcium was evaluated in the presence or absence of vardenafil, nifedipine, verapamil or 1H-[1,2,4] oxadiazolo[4,3-a] quinoxalin-1-one (ODQ).

RESULTS

Vardenafil attenuated pulmonary artery contraction induced by phenylephrine in the presence and absence of endothelium. In addition, vardenafil attenuated both Phe or KCl-induced contraction but, it's effect on the KCl dose-response curve was more significant. Vardenafil also inhibited the contractile response induced by calcium in a dose-dependent manner. Addition of nifedipine or verapamil did not significantly alter this effect while ODQ incubation significantly inhibited vardenafil-induced relaxation.

CONCLUSION

From these findings, it was proposed that vardenafil relaxed rat pulmonary artery through inhibiting calcium influx.

Gastrointestinal effect of methanol extract of Radix Aucklandiae and selected active substances on the transit activity of rat isolated intestinal strips

CONTEXT

Radix Aucklandiae, the dry rhizome of Aucklandia lappa Decne (Asteraceae), enjoyed traditional popularity for its antidiarrheal effects. Although there are many investigations on its chemical constituents and pharmacologic actions, few studies explaining its activity and mechanism in gastrointestinal disorders are available.

OBJECTIVE

In this paper, we focused on the effects of the methanol extract of R. Aucklandiae (RA ext) on gastrointestinal tract, so as to assess some of the possible mechanisms involved in the clinical treatment.

MATERIALS AND METHODS

In vivo, in neostigmine-induced mice and normal mice, after intragastric administration, RA ext (100, 200, 300, and 400 mg/kg) was studied on gastrointestinal transit including gastric emptying and small intestinal motility. Meanwhile, in vitro, the effect of it (0.1, 0.2, 0.3, and 0.4 mg/mL) on the isolated tissue preparations of rat jejunum was also investigated, as well as costunolide and dehydrocostuslactone which were the main constituents.

RESULTS

In vivo, the gastric emptying increased and intestinal transit decreased after the administration of RA ext in normal mice. However, RA ext inhibited the gastric emptying and the intestinal transit throughout the concentrations in neostigmine-induced mice. In vitro, RA ext caused inhibitory effect on the spontaneous contraction of rat-isolated jejunum in a dose-dependent manner ranging from 0.1 to 0.4 mg/mL, and it also relaxed the acetylcholine chloride (Ach, 10(-5) M), 5-hydroxytryptamine (5-HT, 200 μM)-induced, and K(+) (60 mM)-induced contractions. RA ext shifted the Ca(2+) concentration-response curves to right, similar to that caused by verapamil (0.025 mM). The Ca(2+) concentration-response curves were shifted by costunolide (CO) (5.4, 8.1, and 10.8 μg/mL), dehydrocostuslactone (DE) (4.6, 6.9, and 9.2 μg/mL), costunolide-dehydrocostuslactone (CO-DE) (5.4-4.6, 8.1-6.9, and 10.8-9.2 μg/mL) to the right, similar to that caused by verapamil (0.01 mM).

DISCUSSION AND CONCLUSION

These results indicate that RA ext played a spasmolytic role in gastrointestinal motility, which is probably mediated through the inhibition of muscarinic receptors, 5-HT receptors, and calcium influx. The presence of cholinergic and calcium antagonist constituents may be the compatibility of CO and DE. All these results provide a pharmacological basis for its clinical use in the gastrointestinal tract.

Anti-diarrhoeal activity of methanol extract of Santalum album L. in mice and gastrointestinal effect on the contraction of isolated jejunum in rats

ETHNOPHARMACOLOGICAL RELEVANCE

Santalum album L., namely Sandalwood, honored as "Green Gold", is a traditional Chinese herb which has the effects of anti-diarrhoeal and antibacterial activity. But there is limit scientific study on its activity and mechanism in gastrointestinal disorders.

MATERIALS AND METHODS

in vivo, after intragastric administration, the methanol extract of Sandalwood (SE) (200, 400 and 800 mg/kg) were studied in castor oil-induced diarrhoea mice. By the test of small intestinal hyperfunction induced by neostigmine, SE was studied on gastrointestinal transit including gastric emptying and small intestinal motility. Meanwhile, in vitro, the effects of SE (0.02, 0.05, 0.1, 0.2, 0.3, 0.4 mg/mL) on the isolated tissue preparations of rat jejunum were also investigated. The rat jejunum strips were pre-contracted with acetylcholine (Ach; 10(-6)M), 5-hydroxytryptamine (5-HT, 200 μM) or potassium chloride (KCl; 60 mM) and tested in the presence of SE. In addition, the possible myogenic effect was analyzed in the pretreatment of the jejunum preparations with SE or verapamil in Ca(2+)-free high-K(+) (60 mM) solution containing EDTA.

RESULTS

At doses of 200, 400 and 800 mg/kg, SE showed significant anti-diarrhoeal activity against castor oil-induced diarrhoea as compared with the control. At the same doses, it also inhibited the gastric emptying and small intestinal motility in the mice of which small intestinal hyperfunction induced by neostigmine. It caused inhibitory effects on the spontaneous contraction of rat-isolated jejunum in dose-dependent manner ranging from 0.02 to 0.4 mg/mL, and it also relaxed the Ach-induced, 5-HT-induced and K(+)-induced contractions. SE shifted the Ca(2+) concentration-response curves to right, similar to that caused by verapamil (0.025 mM).

CONCLUSIONS

These findings indicated that SE played a spasmolytic role in gastrointestinal motility which was probably mediated through inhibition of muscarinic receptors, 5-HT receptors and calcium influx. All these results provide pharmacological basis for its clinical use in gastrointestinal tract.

Metabolomics analysis reveals that bile acids and phospholipids contribute to variable responses to low-temperature-induced ascites syndrome

Hepatic metabolomic profiles of low-temperature induced ascites syndrome showed disturbances in the metabolism of bile acids and phospholipid.

Hypoxia promotes cell proliferation by modulating E2F1 in chicken pulmonary arterial smooth muscle cells

In this study, we sought to investigate the expression of the transcription factor E2F1 in chicken pulmonary arterial smooth muscle cells upon hypoxia exposure, as well as the role that E2F1 played in the regulation of cell proliferation. Isolated chicken pulmonary arterial smooth muscle cells were subjected to hypoxia or normoxia for indicated time points. Cell viability, DNA synthesis, cell cycle profile, and expression of E2F1 were analyzed. The results showed that hypoxia promoted cell proliferation and DNA synthesis which was accompanied by an increased S phase entry and upregulation of E2F1 at mRNA and protein levels. Using siRNA technology, we demonstrated that gene inactivation of endogenous E2F1 abolished hypoxia-induced cell proliferation, DNA synthesis, and S phase entry compared with negative siRNA transfected cells. These results suggest that hypoxia-induced proliferation is mediated by inducing E2F1 in chicken pulmonary arterial smooth muscle cells.

Calcium antagonists, diltiazem and nifedipine, protect broilers against low temperature-induced pulmonary hypertension and pulmonary vascular remodeling

This study was designed to determine whether calcium antagonists, diltiazem and nifedipine, can depress low temperature-induced pulmonary hypertension (PH) in broilers (also known as ascites) and to characterize their efficacy on hemodynamics and pulmonary artery function. Chicks were randomly allocated into six experimental groups and orally administered with vehicle, 5.0 mg/kg body weight (BW)/12 h nifedipine or 15.0 mg/kg BW/12 h diltiazem from 16 to 43 days of age under low temperature. The mean pulmonary arterial pressure (mPAP), the ascites heart index (AHI), the erythrocyte packed cell volume (PCV) and the relative percentage of medial pulmonary artery thickness were examined on days 29, 36 and 43. The data showed that administration of diltiazem protected broilers from low temperature-induced pulmonary hypertension and vascular remodeling. Although nifedipine prevented mPAP from increasing during the early stage, it did not suppress the development of PH during the late stage and did not keep heart rate (HR), PCV, AHI and the thickness of pulmonary small artery smooth muscle layer at the normal levels. Taken together, our results showed that diltiazem can effectively prevent low temperature-induced pulmonary hypertension in broilers with fewer side-effects and may be a potential compound for the prevention of this disease in poultry industry.

Genistein attenuates low temperature induced pulmonary hypertension in broiler chicks by modulating endothelial function

Pulmonary arterial hypertension is characterized by high pulmonary blood pressure, vascular remodeling and right ventricular hypertrophy. In the present study, we investigated whether genistein would prevent the development of low temperature-induced pulmonary hypertension in broilers. Hemodynamic parameters, vascular remodeling, the expression of endothelial nitric oxide and endothelin-1 content in lung tissue were evaluated. The results demonstrated that genistein significantly reduced pulmonary arterial hypertension and suppressed pulmonary arterial vascular remodeling without affecting broilers' performance. The beneficial effects appeared to be mediated by restoring endothelial function especially endothelial nitric oxide and endothelin-1, two critical vasoactive molecules that associated with the development of hypertension. Genistein supplementation might be a potential therapeutic strategy for the treatment of pulmonary hypertension.

Isoliquiritigenin, a flavonoid from licorice, plays a dual role in regulating gastrointestinal motility in vitro and in vivo

Licorice root has been used for years to regulate gastrointestinal function in traditional Chinese medicine. This study reveals the gastrointestinal effects of isoliquiritigenin, a flavonoid isolated from the roots of Glycyrrhiza glabra (a kind of Licorice). In vivo, isoliquiritigenin produced a dual dose-related effect on the charcoal meal travel, inhibitory at the low doses, while prokinetic at the high doses. In vitro, isoliquiritigenin showed an atropine-sensitive concentration-dependent spasmogenic effect in isolated rat stomach fundus. However, a spasmolytic effect was observed in isolated rabbit jejunums, guinea pig ileums and atropinized rat stomach fundus, either as noncompetitive inhibition of agonist concentration-response curves, inhibition of high K(+) (80 mM)-induced contractions, or displacement of Ca(2+) concentration-response curves to the right, indicating a calcium antagonist effect. Pretreatment with N(omega)-nitro-L-arginine methyl ester (L-NAME; 30 microM), indomethacin (10 microM), methylene blue (10 microM), tetraethylammonium chloride (0.5 mM), glibenclamide (1 microM), 4-aminopyridine (0.1 mM), or clotrimazole (1 microM) did not inhibit the spasmolytic effect. These results indicate that isoliquiritigenin plays a dual role in regulating gastrointestinal motility, both spasmogenic and spasmolytic. The spasmogenic effect may involve the activating of muscarinic receptors, while the spasmolytic effect is predominantly due to blockade of the calcium channels.

Histamine-induced modulation of vascular tone in the isolated chicken basilar artery: a possible involvement of endothelium

We investigated the histamine responsiveness of basilar arterial rings isolated from chicken. We also examined whether endothelial cells were involved in the histamine responsiveness and in resting vascular tone. Histamine induced concentration-dependent relaxations under condition of precontraction by 5-hydroxytryptamine. The concentration-response curve for histamine was shifted to the right by diphenhydramine (a H(1) receptor antagonist), cimetidine (a H(2) receptor antagonist) and Nomega-nitro-L-arginine (L-NNA, a nitric oxide synthase inhibitor); however, indomethacin (a cyclooxygenase inhibitor) had no significant effect on it. Treatment with L-NNA shifted the concentration-response curve of histamine to the right in the presence of cimetidine, but not in the presence of diphenhydramine. Treatment with cimetidine shifted the concentration-response curve of histamine to the right in the presence of diphenhydramine. L-NNA induced a contraction but indomethacin had no effect on the resting vascular tone. These results suggest that histamine-induced relaxation is mediated via activation of H(1) receptors located on endothelial cells and H(2) receptors located on smooth muscle cells. The main relaxing factor released from endothelial cells is probably nitric oxide. The resting vascular tone was modulated by spontaneously released nitric oxide, but not by prostaglandins or thromboxane A(2).