Regulation of signal transducer and activator of transcription 3 and apoptotic pathways by betaine attenuates isoproterenol-induced acute myocardial injury in rats

Investigation of the Gastroprotective Effect of Betaine-Homocysteine Homeostasis on Oxidative Stress, Inflammation and Apoptosis in Ethanol-Induced Ulcer Model

Background: There is a growing interest in the use of natural compounds for the treatment of gastric ulcers. The multifunctional roles of betaine in various diseases make this natural substance a favorable pre-drug for ulcer treatment. This study aims to determine the competence of betaine in gastroprotection against ethanol-induced damage and to explore underlying mechanisms considering its effects on liver and kidney activity and blood parameters.Methods: Wistar albino rats were orally treated with vehicle (distilled water) or betaine (250 mg/kg) for twenty-one days and then ulcer formation was induced by ingestion of 75% ethanol. Gastric mucosal damage was evaluated by gross examination and histopathological analysis. Homocysteine levels, lipid peroxidation, total antioxidant status (TAS), total oxidant status (TAS), antioxidant enzymes and pro-inflammatory and anti-inflammatory cytokines levels were assessed by enzyme-linked immunosorbent assay (ELISA) or immunohistochemistry. Furthermore, routine biochemical tests were performed and hematological parameters were analyzed.Results: Betaine ameliorated any gastric mucosal damage and reduced homocysteine levels significantly. The TOS and malondialdehyde (MDA) levels were decreased while the TAS, glutathione (GSH) levels and catalase (CAT) activity were increased upon the betaine treatment. Betaine reduced apoptosis by regulating Bax and Bcl-2 levels, however, it did not alter inflammatory mediators. Additionally, betaine improved serum potassium (K⁺) and blood urea nitrogen (BUN) levels, whereas it increased alanine aminotransferase (ALT) levels and impaired hematological parameters.Conclusions: Altogether, these data illustrated that betaine exhibits a gastroprotective effect against ulcers through the homocysteine pathway by modulating oxidative stress in the gastric tissue; however, its systemic effects should not be ignored.

Integrated metabolomics and network pharmacology to reveal the mechanisms of Guizhi-Fuling treatment for myocardial ischemia

Myocardial ischemia is a cardio-physiological condition caused by a decrease in blood perfusion to the heart, resulting in reduced oxygen supply and abnormal myocardial energy metabolism. Guizhi-Fuling (GZFL) is effective in treating Myocardial ischemia. However, its mechanism of action remains unclear and requires further exploration. we hope to reveal the mechanisms of GZFL treating Myocardial ischemia by integrating metabolomics and network pharmacology. In this study, myocardial metabolomic analysis was first performed using GC-MS to discover the potential mechanism of action of GZFL on myocardial ischemia. Then, network pharmacology was used to analyze key pathways and construct a pathway-core target network. Molecular docking was used to validate core targets in network pharmacological signaling pathways. Finally, western blots were used to verify core targets of metabolomics and network pharmacology integrated pathways as well as key targets in signaling pathways. As a result, we identified 22 important biomarkers of GZFL for the treatment of myocardial ischemia. Most of these metabolites were restored by modulation after GZFL treatment. Based on the network pharmacology, 297 targets of GZFL in the treatment of myocardial ischemia were obtained. The further comprehensive analysis focused on 3 key targets, including Tyrosine hydroxylase (TH), myeloperoxidase (MPO), and phosphatidylinositol 3-kinases (PIK3CA), and their associated metabolites and pathways. Compared with the model group, the protein expression levels of TH, MPO and PIK3CA were decreased in GZFL. Therefore, the mechanism of GZFL for treating myocardial ischemia may be to inhibit myocardial inflammatory factors, reduce myocardial inflammation, and restore endothelial function, while regulating norepinephrine release and uric acid concentration.

PM2.5 Exposure Lowers Mitochondrial Endurance During Cardiac Recovery in a Rat Model of Myocardial Infarction

Many studies have reported the negative effect of PM_2.5 exposure on heart function which is likely to impair postcardiac surgery rehabilitation that is involved in recovery and wound healing, yet the direct effects of PM_2.5 from diesel exhaust (DPM) on cardiac recovery is unknown. To study the impact of DPM on cardiac recovery and repair, we utilized isoproterenol induced myocardial infarction (MI) model where female rats were exposed to DPM prior and after MI induction. The experimental groups comprise of normal, ISO control, DPM control (42 days of exposure), DPM exposed prior (21 days) and after (21 days) MI induction (D + I + D) and DPM exposed (21 days) after MI (I + D). Post-MI rat hearts from D + I + D group exhibited higher fibrosis, elevated cardiac injury and altered electrophysiology, where this pathology was also observed in I + D group animals which was mild. Loss of mitochondrial quality was evident in DPM exposed animals with and without MI, where severe mitochondrial damage persisted in D + I + D group. In addition, these animals showed striking decline in ETC enzyme activity, ATP levels, mitochondrial copy number and down regulation of PGC1-α, TFAM and POLG along with the genes involved in mitophagy and mitofusion. Besides, the MI associated inactivation of cardio protective signalling pathways like PI3K and Akt were persistent in D + I + D group. In fact, I + D group animals also showed a similar pattern of change, but in a mild form. Taken together, exposure to PM_2.5 increases the risk, frequency or progression of MI by impairing the recovery potential of the myocardium.

High Betaine and Dynamic Increase of Betaine Levels Are Both Associated With Poor Prognosis of Patients With Pulmonary Hypertension

Background and Objective

The association between plasma betaine levels and cardiovascular diseases (CVDs) has been revealed except for pulmonary hypertension (PH). In this study, we aimed to explore the role of betaine in patients with PH.

Methods

Inpatients with PH at Fuwai Hospital were enrolled after excluding relative comorbidities. Each patient received at least one follow-up through a clinical visit, and the fasting blood was obtained both at the first and second hospitalization for betaine detection. The primary endpoint was defined as composite outcome events and the mean duration was 14.3 (6.9, 21.3) months. The associations of betaine and changes of betaine (Δbetaine) with disease severity and prognosis were explored.

Results

Finally, a total of 216 patients with PH were included and the medians for betaine plasma levels in the total patients group, low betaine, and high betaine groups were 49.8 (39.0, 68.3) μM, 39.0 (33.5, 44.7) μM, and 68.1 (57.8, 88.7) μM, respectively. High betaine was associated with poor World Health Organization Functional Class (WHO-FC), increased N-terminal pro-brain natriuretic peptide (NT-proBNP), low tricuspid annular plane systolic excursion (TAPSE), and cardiac output index even after adjusting for confounders. Patients with high betaine were over twice the risk to receive the poor prognosis than those with a low level [hazard ratio (HR) = 2.080, (95% CI: 1.033–4.188)]. Moreover, the decrease of betaine level after further treatment was positively correlated to ΔNT-proBNP indicating Δbetaine might be an effector of disease severity, and dynamic increase of betaine was also associated with poor prognosis in PH.

Conclusion

Betaine was associated with disease severity and might be an effector in PH. Patients with increased levels or with dynamic rise of betaine heralded a poor prognosis.

Inhalation of PM2.5 from diesel exhaust promote impairment of mitochondrial bioenergetics and dysregulate mitochondrial quality in rat heart: implications in isoproterenol-induced myocardial infarction model

Aim: Ambient exposure of PM_2.5 from diesel exhaust (termed as diesel particulate matter [DPM]) can induce cardiotoxicity that can be manifested into myocardial ischemia/infarction, where the survival depends on mitochondrial function. The mechanism for DPM-induced mitochondrial dysfunction is yet to be elucidated and the consequential impact of impaired mitochondria on the severity of myocardial infarction (MI) has not been established.Materials and methods: Female Wistar rats were exposed to DPM (0.5 mg/ml) for 3 h daily (to achieve a PM_2.5 concentration of 250 µg/m³) for 21 d trailed by an induction of MI using isoproterenol (ISO).Conclusion: DPM exposure altered the basal ECG pattern and increased heart weight (HW) to body weight (BW) ratio from control. Loss of mitochondrial quality in the cardiac tissue was observed in DPM exposed animals, measured via declined ETC enzyme activity, reduced ATP levels, high oxidative stress, low mitochondrial copy number, and low expression of the mitochondrial genes involved in mitophagy (PINK and PARKIN) and mitochondrial fusion (MFN-1). Subsequent induction of MI in DPM exposed animals (DPM + ISO) further deteriorated the normal sinus rhythm, accompanied by elevated plasma CK and LDH level, increased myocardial caspase activity, downregulation of Peroxisome proliferator-activated receptor-gamma coactivator (PGC1-α), transcription factor A (TFAM), DNA polymerase subunit gamma (POLG), and other mitochondrial quality control genes. Based on these results, we conclude that DPM alters the electrophysiology and ultrastructure of the heart that aggravates the MI-induced cardiotoxicity, where the diminished mitochondrial quality can be the potential contributor.

Inhibition of NF-κB and the oxidative stress -dependent caspase-3 apoptotic pathway by betaine supplementation attenuates hepatic injury mediated by cisplatin in rats

BACKGROUND

Cisplatin is a major anti-cancer drug commonly used in the treatment of various cancers; nevertheless, the associated hepatotoxicity has limited its clinical application. The aim of this investigation is to test the impact of betaine supplementation on cisplatin-induced hepatotoxicity.

METHODS

Animals were allocated into four groups; normal control group (control betaine group (250 mg/kg/day, po for twenty six days), cisplatin group (single injection of 7 mg/kg, ip) and betaine + cisplatin group (received betaine for twenty one days before cisplatin injection and daily after cisplatin for five days).

RESULTS

Cisplatin-induced liver injury was confirmed by increased alanine aminotransferase (ALT) and aspartate aminotransferase (AST) levels. Cisplatin elevated lipid peroxides, and reduced the concentrations of reduced glutathione (GSH), glutathione peroxidase (GSH-Px), catalase and superoxide dismutase (SOD) in hepatic tissues. Cisplatin increased the inflammatory mediators; nitrite and tumor necrosis factor-α (TNF- α) in hepatic tissues. Increased gene expressions of the apoptotic marker, caspase-3 and nuclear factor-kappa B (NF-κB) were observed in hepatic tissues of cisplatin-treated rats. All these changes were further confirmed by histopathological findings in cisplatin group. Pre-treatment with betaine reduced serum aminotransferases (ALT and AST), and lowered hepatic concentrations of lipid peroxides, nitrite and TNF-α while increased SOD, GSH, catalase, and GSH-Px concentrations. Moreover, the histological and immunohistochemical changes were improved.

CONCLUSION

The suppression of NF-κβ-mediated inflammation, oxidative stress, and caspase-3 induced apoptosis are possible mechanisms to the observed hepatoprotective effect of betaine.

Betaine modulates oxidative stress, inflammation, apoptosis, autophagy, and Akt/mTOR signaling in methionine-choline deficiency-induced fatty liver disease

We examined the effects of betaine, an endogenous and dietary methyl donor essential for the methionine-homocysteine cycle, on oxidative stress, inflammation, apoptosis, and autophagy in methionine-choline deficient diet (MCD)-induced non-alcoholic fatty liver disease (NAFLD). Male C57BL/6 mice received standard chow (control), standard chow and betaine (1.5% w/v in drinking water), MCD, or MCD and betaine. After six weeks, serum and liver samples were collected for analysis. Betaine reduced MCD-induced increase in liver transaminases and inflammatory infiltration, as well as hepatosteatosis and serum levels of low-density lipoprotein, while it increased that of high-density lipoprotein. MCD-induced hepatic production of reactive oxygen and nitrogen species was significantly reduced by betaine, which also improved liver antioxidative defense by increasing glutathione content and superoxide-dismutase, catalase, glutathione peroxidase, and paraoxonase activity. Betaine reduced the liver expression of proinflammatory cytokines tumor necrosis factor and interleukin-6, as well as that of proapoptotic mediator Bax, while increasing the levels of anti-inflammatory cytokine interleukin-10 and antiapoptotic Bcl-2 in MCD-fed mice. In addition, betaine increased the expression of autophagy activators beclin 1, autophagy-related (Atg)4 and Atg5, as well as the presence of autophagic vesicles and degradation of autophagic target sequestosome 1/p62 in the liver of NAFLD mice. The observed effects of betaine coincided with the increase in the hepatic phosphorylation of mammalian target of rapamycin (mTOR) and its activator Akt. In conclusion, the beneficial effect of betaine in MCD-induced NAFLD is associated with the reduction of liver oxidative stress, inflammation, and apoptosis, and the increase in cytoprotective Akt/mTOR signaling and autophagy.

Tetramethylpyrazine exerts a protective effect against injury from acute myocardial ischemia by regulating the PI3K/Akt/GSK-3β signaling pathway

Objective

We investigated the protective effect of tetramethylpyrazine (TMP) on injury related to acute myocardial ischemia (AMI) induced by isoproterenol (ISO).

Materials and methods

Rats were randomly assigned to five groups: control, ISO, ISO + propranolol (10 mg/kg), ISO + TMP (10 mg/kg) and ISO + TMP (20 mg/kg). The rats in the three ISO + groups were pretreated with propranolol or TMP, while the rats in the control and ISO groups were pretreated with an equal volume of saline. Afterwards, the rats in the four administration groups were subcutaneously injected with ISO for two consecutive days. The levels of creatine kinase (CK), lactate dehydrogenase (LDH), superoxide dismutase (SOD), malondialdehyde (MDA), tumor necrosis factor-α (TNF-α), interleukin-6 (IL-6) and IL-1β in the serum were measured using ELISA. The expressions of B-cell lymphoma-associated X-2 (Bax-2), B-cell lymphoma-2 (Bcl-2), phosphoinositide-3-kinase (PI3K), protein kinase B (Akt), glycogen synthase kinase 3β (GSK-3β), MDA5 and SOD1 were determined using western blotting assay. The phosphorylation of PI3K, Akt and GSK-3β were also determined using western blotting assay. The left ventricles of the rats were extracted and stained using hematoxylin and eosin (H&E). The ST segment was recorded using electrocardiograms (ECGs).

Results

Administration of TMP (10, 20 mg/kg) reduced the levels of MDA and CK and the activities of SOD and LDH in the serum. Pretreatment with TMP significantly reduced the levels of pro-inflammatory cytokines, including IL-1β, IL-6 and TNF-α. Treatment with TMP also improved the histopathological alteration and decreased the ST elevation. Furthermore, TMP ameliorated the expressions of Cu, SOD1, MDA5, Bax-2, Bcl-2, p-PI3K, p-Akt and p-GSK-3β in ISO-induced rats.

Conclusions

Tetramethylpyrazine protected against injury due to AMI by regulating the PI3K/Akt /GSK-3β signaling pathway.

Betaine Attenuates Monocrotaline-Induced Pulmonary Arterial Hypertension in Rats via Inhibiting Inflammatory Response

Background: Pulmonary arterial hypertension (PAH) is characterized by increased pulmonary vascular resistance, leading to right ventricular failure and death. Recent studies have suggested that chronic inflammatory processes are involved in the pathogenesis of PAH. Several studies have demonstrated that betaine possesses outstanding anti-inflammatory effects. However, whether betaine exerts protective effects on PAH by inhibiting inflammatory responses in the lungs needs to be explored. To test our hypothesis, we aimed to investigate the effects of betaine on monocrotaline-induced PAH in rats and attempted to further clarify the possible mechanisms. Methods: PAH was induced by monocrotaline (50 mg/kg) and oral administration of betaine (100, 200, and 400 mg/kg/day). The mean pulmonary arterial pressure, right ventricular systolic pressure, and right ventricle hypertrophy index were used to evaluate the development of PAH. Hematoxylin and eosin staining and Masson staining were performed to measure the extents of vascular remodeling and proliferation in fibrous tissue. Monocyte chemoattractant protein-1 (MCP-1) and endothelin-1 (ET-1) were also detected by immunohistochemical staining. Nuclear factor-κB (NF-κB), tumor necrosis factor alpha (TNF-α), and interleukin-1β (IL-1β) were assessed by Western blot. Results: This study showed that betaine improved the abnormalities in right ventricular systolic pressure, mean pulmonary arterial pressure, right ventricle hypertrophy index, and pulmonary arterial remodeling induced by monocrotaline compared with the PAH group. The levels of MCP-1 and ET-1 also decreased. Western blot indicated that the protein expression levels of NF-κB, TNF-α, and IL-1β significantly decreased (p < 0.01). Conclusion: Our study demonstrated that betaine attenuated PAH through its anti-inflammatory effects. Hence, the present data may offer novel targets and promising pharmacological perspectives for treating monocrotaline-induced PAH.

Molecular understanding of the protective role of natural products on isoproterenol-induced myocardial infarction: A review

Modern medicine has been used to treat myocardial infarction, a subset of cardiovascular diseases, and have been relatively effective but not without adverse effects. Consequently, this issue has stimulated interest in the use of natural products, which may be equally effective and better tolerated. Many studies have investigated the cardioprotective effect of natural products, such as plant-derived phytochemicals, against isoproterenol (ISO)-induced myocardial damage; these have produced promising results on the basis of their antioxidant, anti-atherosclerotic, anti-apoptotic and anti-inflammatory activities. This review briefly introduces the pathophysiology of myocardial infarction (MI) and then addresses the progress of natural product research towards its treatment. We highlight the promising applications and mechanisms of action of plant extracts, phytochemicals and polyherbal formulations towards the treatment of ISO-induced myocardial damage. Most of the products displayed elevated antioxidant levels with decreased oxidative stress and lipid peroxidation, along with restoration of ionic balance and lowered expression of myocardial injury markers, pro-inflammatory cytokines, and apoptotic parameters. Likewise, lipid profiles were positively altered and histopathological improvements could be seen from, for example, the better membrane integrity, decreased necrosis, edema, infarct size, and leukocyte infiltration. This review highlights promising results towards the amelioration of ISO-induced myocardial damage, which suggest the direction for future research on natural products that could be used to treat MI.