Immune Cells in the Spleen of Mice Mediate the Inflammatory Response Induced by Mannheimia haemolytica A2 Serotype.

(1) Background: Mannheimia haemolytica (M. haemolytica) is an opportunistic pathogen and is mainly associated with respiratory diseases in cattle, sheep, and goats. (2) Methods: In this study, a mouse infection model was established using a M. haemolytica strain isolated from goats. Histopathological observations were conducted on various organs of the mice, and bacterial load determination and RNA-seq analysis were specifically performed on the spleens of the mice. (3) Results: The findings of this study suggest that chemokines, potentially present in the spleen of mice following a M. haemolytica challenge, may induce the migration of leukocytes to the spleen and suppress the release of pro-inflammatory factors through a negative feedback regulation mechanism. Additionally, an interesting observation was made regarding the potential of hematopoietic stem/progenitor cells congregating in the spleen to differentiate into immune cells, which could potentially collaborate with leukocytes in their efforts to counteract M. haemolytica invasion. (4) Conclusions: This study revealed the immune regulation mechanism induced by M. haemolytica in the mouse spleen, providing valuable insights into host-pathogen interactions and offering a theoretical basis for the prevention, control, and treatment of mannheimiosis.

[Mechanism of Jiming Powder in ameliorating heart failure with preserved ejection fraction based on metabolomics].

In this study, untargeted metabolomics was conducted using the liquid chromatography-tandem mass spectrometry(LC-MS/MS) technique to analyze the potential biomarkers in the plasma of mice with heart failure with preserved ejection fraction(HFpEF) induced by a high-fat diet(HFD) and nitric oxide synthase inhibitor(Nω-nitro-L-arginine methyl ester hydrochloride, L-NAME) and explore the pharmacological effects and mechanism of Jiming Powder in improving HFpEF. Male C57BL/6N mice aged eight weeks were randomly assigned to a control group, a model group, an empagliflozin(10 mg·kg~(-1)·d~(-1)) group, and high-and low-dose Jiming Powder(14.3 and 7.15 g·kg~(-1)·d~(-1)) groups. Mice in the control group were fed on a low-fat diet, and mice in the model group and groups with drug intervention were fed on a high-fat diet. All mice had free access to water, with water in the model group and Jiming Powder groups being supplemented with L-NAME(0.5 g·L~(-1)). Drugs were administered on the first day of modeling, and 15 weeks later, blood pressure and cardiac function of the mice in each group were measured. Heart tissues were collected for hematoxylin-eosin(HE) staining to observe pathological changes and Masson's staining to observe myocardial collagen deposition. Untargeted metabolomics analysis was performed on the plasma collected from mice in each group, and metabolic pathway analysis was conducted using MetaboAnalyst 5.0. The results showed that the blood pressure was significantly lower and the myocardial concentric hypertrophy and left ventricular diastolic dysfunction were significantly improved in both the high-dose and low-dose Jiming Powder groups as compared with those in the model group. HE and Masson staining showed that both high-dose and low-dose Jiming Powder significantly alleviated myocardial fibrosis. In the metabolomics experiment, 23 potential biomarkers were identified and eight strongly correlated metabolic pathways were enriched, including linoleic acid metabolism, histidine metabolism, alpha-linolenic acid metabolism, glycerophospholipid metabolism, purine metabolism, porphyrin and chlorophyll metabolism, arachidonic acid metabolism, and pyrimidine metabolism. The study confirmed the pharmacological effects of Jiming Powder in lowering blood pressure and ameliorating HFpEF and revealed the mechanism of Jiming Powder using the metabolomics technique, providing experimental evidence for the clinical application of Jiming Powder in treating HFpEF and a new perspective for advancing and developing TCM therapy for HFpEF.

[Role of macrophages in heart failure and traditional Chinese medicine intervention].

As the disease with high morbidity and mortality in the world, heart failure affects the development of human society. Due to its complicated pathology and limited treatment options, it is urgent to discover new disease targets and develop new treatment strategies. As innate immune cells accompanied by the evolution of heart failure, macrophages play an important role in cardiac homeostasis and stress. In recent years, the role of macrophages in the heart has attracted more and more attention as a potential target for heart failure intervention, and the research on cardiac macrophages has made important progress. Traditional Chinese medicine(TCM) has significant effects on regulating inflammatory response, treating heart failure, and maintaining homeostasis. In this article, researches on the functions of cardiac macrophages and application of TCM were reviewed from the source and classification of cardiac macrophages and the relationship of macrophages and cardiac inflammation, myocardial fibrosis, cardiac angiogenesis, and cardiac electrical conduction, which provided a basis for further basic research and clinical applications.

Evaluation of the transverse aortic constriction model in ICR and C57BL/6J mice.

Transverse aortic constriction (TAC) is a frequently used model to investigate pressure overload-induced progressive heart failure (HF); however, there is considerable phenotypic variation among different mouse strains and even sub-strains. Moreover, less is known about the TAC model in ICR mice. Therefore, to determine the suitability of the ICR strain for TAC-induced HF research, we compared the effects of TAC on ICR and C57BL/6J mice at one, two and four weeks post-TAC via echocardiography, organ index, morphology, and histology. At the end of the study, behavior and gene expression patterns were assessed, and overall survival was monitored. Compared to the sham-operated mice, ICR and C57BL/6J mice displayed hypertrophic phenotypes with a significant increase in ventricle wall thickness, heart weight and ratio, and cross-sectional area of cardiomyocytes after a 2-week TAC exposure. In addition, ICR mice developed reduced systolic function and severe lung congestion 4 weeks post-TAC, whereas C57BL/6J did not. Besides, ICR mice demonstrated comparable survival, similar gene expression alteration but severer fibrotic remodeling and poor behavioral performance compared to the C57BL/6J mice. Our data demonstrated that ICR was quite sensitive to TAC-induced heart failure and can be an ideal research tool to investigate mechanisms and drug intervention for pressure overload-induced HF.

[Common anti-inflammatory effects of heat-clearing and toxin-removing Chinese medicines on diverse cardiovascular diseases].

Cardiovascular diseases seriously affect human health and their prevalence continues to increase with the aging of the population. The integrated therapy of traditional Chinese medicine(TCM) and western medicine for cardiovascular diseases has achieved certain results, but it is still faced with new challenges. Studies have shown that inflammation plays an important role in the development of cardiovascular diseases and some of these mechanisms have common features. For example, in cardiovascular diseases, C-C motif chemokine receptor 2(CCR2)-expressing macrophages increase and promote inflammation, and excessive activation of NOD-like receptor protein 3(NLRP3) inflammasome leads to the elevation of inflammatory factors. There is also new understanding of the pathogenesis and treatment of cardiovascular diseases in TCM. The heat-toxicity theory in cardiovascular diseases and the therapeutic principle of clearing heat and removing toxin have attracted attention. The clinical and pharmacological studies on the treatment of cardiovascular diseases such as Huanglian Jiedu Decoction and Simiao Yong'an Decoction are also gradually increasing. The present study analyzed the common features of the inflammatory response mechanisms in diverse cardiovascular diseases and discussed the significance of the prevention and treatment of diverse cardiovascular diseases by the treatment method of clearing heat and removing toxin to regulate inflammation, which is expected to provide new ideas and references for clinical treatment and drug research on cardiovascular diseases with the same treatment method for different diseases.

Cryptochlorogenic acid and its metabolites ameliorate myocardial hypertrophy through a HIF1α-related pathway.

Cryptochlorogenic acid (4-CQA) is a phenolic acid that has antioxidant and anti-inflammatory activities. Our preliminary study found that 4-CQA has a good effect on isoproterenol (ISO)-induced myocardial hypertrophy, while the mechanism remains largely unknown. This study aimed at delineating the metabolites and metabolic pathways of 4-CQA using liquid mass spectrometry and molecular biotechnology, exploring possible active metabolites and the mechanism of myocardial hypertrophy amelioration in H9c2 cells, and finally, investigating the pharmacokinetics of 4-CQA and its active metabolites in vivo. In summary, 56 potential effective metabolites were distinguished in rat urine, feces, plasma samples and heart tissue after intragastric administration of 4-CQA, and the main metabolic reaction types of 4-CQA included hydrogenation, methylation, glucuronidation, sulfation, hydration and their composite reactions in in vivo biotransformation. Besides, 4-CQA and its main active metabolites, caffeic acid and 4-O-feruloylquinic acid, significantly ameliorated pathological cardiac hypertrophy of H9c2 cells treated with ISO based on the Akt/mTOR/HIF-1α pathway. In addition, this study demonstrated that the prototype drugs 4-CQA and 4-O-ferulylquinic acid generally exhibit similar pharmacokinetic characteristics and caffeic acid presents relatively late peak time and low peak concentration in rats, which make them suitable candidate drugs.

The prevalence of smoking in male medical students from 16 Chinese medical colleges and the associated factors.

BACKGROUND: The prevalence of smoking among Chinese medical students in medical colleges is a matter of significant concern. This study aimed to explore the prevalence of smoking and the associated factors among these students. METHODS: A total of 7,728 students from 16 colleges in 12 provinces were surveyed to measure their smoking behaviors, attitudes toward tobacco control, and knowledge about smoking risk. An evaluation of campus environment and policy was conducted at the same time. Frequencies were calculated using weighted estimators for complex sampling. A two-level logistic regression model was used to assess factors associated with current smoking. RESULTS: The prevalence of smoking among male medical students in the 16 medical colleges was 12.8%. Students' participation in smoking, smoking initiation after school enrollment, and intention-to-quit-smoking rates may be influenced by their anti-tobacco attitude, the belief that smoking can help to relieve stress, their parents' smoking behaviors, their best friend's attitude towards smoking and second-hand smoke exposure (SHSE), and their awareness of tobacco hazards. CONCLUSIONS: This study provides sufficient evidence to support the implementation of systematic intervention strategies to decrease the smoking rate among male medical students. These strategies may include tobacco control education, smoking cessation technologies, communication, and the enforcement of smoke-free policies to create a tobacco-controlled campus environment.

Si-Miao-Yong-An decoction preserves cardiac function and regulates GLC/AMPK/NF-κB and GLC/PPARα/PGC-1α pathways in diabetic mice.

BACKGROUND: Diabetic cardiomyopathy (DCM) is a main cause of heart failure and death in diabetic patients. However, countermeasures to limit the development of this disease remain insufficient. Si-Miao-Yong-An decoction (SMYA), a Chinese herbal prescription, exhibits both lipid-lowering and cardiovascular preserving effects, and may have an effect on DCM management. PURPOSE: The current study is aimed to investigate the effects of SMYA on the cardiac function in diabetic mice and the underlying mechanisms involved. METHODS: Streptozotocin-induced diabetic mice were fed intragastrically with SMYA every day for 15 weeks. Cardiac function was assessed by echocardiograph. Histopathological alterations in the heart were determined by hematoxylin/eosin, wheat germ agglutinin, Masson's trichrome, Terminal dUTP nick end-labeling, Oil red O staining, and transmission electron microscopy. The potential involvements of GLC/AMPK/NF-κB and GLC/PPARα/PGC-1α signaling pathways were investigated by western blot and/or immunohistochemical staining. RESULTS: Treatment of diabetic mice with SMYA improved insulin sensitivity, and attenuated the increases of water consumption, food intake, blood glucose, and serum GLC. Furthermore, SMYA ameliorated cardiac systolic and diastolic functions, suppressed the myocardial hypertrophy, fibrosis, apoptosis, inflammation, and lipid accumulation as well as preserved the myofilaments arrangement and mitochondrial integrity. Finally, SMYA downregulated the expressions of GCGR, PGC-1α, PPARα and the phosphorylation of NF-κB, as well as upregulated the phosphorylation of AMPK in the hearts of diabetic mice. CONCLUSIONS: SMYA may ameliorate glucolipid metabolism and cardiac function through the regulation of GLC/AMPK/NF-κB and GLC/PPARα/PGC-1α signaling pathways in diabetic mice, suggesting that this prescription could provide a new source of drug candidates to protect against DCM.

Chlorogenic Acids in Cardiovascular Disease: A Review of Dietary Consumption, Pharmacology, and Pharmacokinetics.

Chlorogenic acids (CGAs) have gained considerable attention as pervasive human dietary constituents with potential cardiovascular-preserving effects. The main sources include coffee, yerba mate, Eucommia ulmodies leaves, and Lonicerae Japonicae Flos. CGA consumption can reduce the risks of hypertension, atherosclerosis, heart failure, myocardial infarction, and other factors associated with cardiovascular risk, such as obesity and type 2 diabetes. This review recapitulates recent advances of CGAs in the cardiovascular-preserving effects, pharmacokinetics, sources, and safety. Emerging evidence indicates that CGAs exhibit circulatory guarding properties through the suppression of oxidative stress, leukocyte infiltration, platelet aggregation, platelet-leukocyte interactions, vascular remodeling, and apoptosis as well as the regulation of glucose and lipid metabolism and vasodilatory action in the cardiovascular system. CGAs exert these effects by acting on complex signaling networks, but the global mechanisms are still not clear. The oral bioavailability of CGA is poor, and there is a potential sensitization concern about CGA. The bioactive metabolites, systematic toxicity, and optimized structure are needed for further identification.

Si-Miao-Yong-An decoction attenuates cardiac fibrosis via suppressing TGF-ß1 pathway and interfering with MMP-TIMPs expression.

BACKGROUND: Myocardial fibrosis is an important pathological feature of pressure overload cardiac remodeling. Si-Miao-Yong-An decoction (SMYAD), a traditional Chinese formula, is now clinically used in the treatment of cardiovascular diseases in China. However, its mechanisms in the prevention of heart failure are not fully revealed. PURPOSE: To determine whether treatment with SMYAD for 4 weeks would lead to changes in collagen metabolism and ventricular remodeling in a mice model of heart failure. METHODS: Mice were subjected to transverse aorta constriction to generate pressure overload induced cardiac remodeling and then were administered SMYAD (14.85 g/kg/day) or captopril (16.5 mg/kg/day) intragastrically for 4 weeks after surgery. Echocardiography and immunohistochemical examination were used to evaluate the effects of SMYAD. The mRNA of collagen metabolism biomarkers were detected. Protein expression of TGF-ß1/Smad and TGF-ß1/TAK1/p38 pathway were assessed by Western blot. RESULTS: SMYAD significantly improved cardiac function, increased left ventricle ejection fraction, and decreased fibrosis area and αSMA expression. Moreover, SMYAD reduced proteins expression related to collagen metabolism, including Col1, Col3, TIMP2 and CTGF. The increased levels of TGF-ß1, Smad2, and Smad3 phosphorylation were attenuated in SMYAD group. In addition, SMYAD reduced the levels of TGF-ß1, p-TAK1 and p-p38 compared with TAC group. CONCLUSIONS: SMYAD improved cardiac fibrosis and heart failure by inhibition of TGF-ß1/Smad and TGF-ß1/TAK1/p38 pathway. SMYAD protected against cardiac fibrosis and maintained collagen metabolism balance by regulating MMP-TIMP expression. Taken together, these results indicate that SMYAD might be a promising therapeutic agent against cardiac fibrosis.