Amentoflavone improves cardiovascular dysfunction and metabolic abnormalities in high fructose and fat diet-fed rats

Beneficial effects of flavonoids on cardiovascular diseases by influencing NLRP3 inflammasome

Cardiovascular diseases (CVDs) are a leading cause of global mortality and have a high incidence rate worldwide. The function of inflammasomes in CVDs has received a lot of attention recently, and the nucleotide-binding domain and leucine-rich repeat protein 3 (NLRP3) inflammasome may be a new target for the prevention and treatment of CVDs. Flavonoids, which are found in food and plant extracts, inhibited inflammation in CVDs by regulating the NLRP3 inflammasome. CB-Dock was used to investigate whether 34 flavonoids from natural products acted on NLRP3 inflammasome. In brief, the PDB format of NLRP3 was selected as a protein file, and 34 flavonoids in SDF format were selected as the ligand file, and then input to CB-Dock for molecular docking. The docking results showed that epigallocatechin-3-gallate (EGCG), amentoflavone, baicalin, scutellarin, vitexin, silibinin, and puerarin had good binding affinities to NLRP3, which could be used as NLRP3 inhibitors, and aid in the discovery of lead compounds for the design and development of CVDs.

Garcinia kola: a critical review on chemistry and pharmacology of an important West African medicinal plant

Garcinia kola Heckel (Clusiaceae) is a tree indigenous to West and Central Africa. All plant parts, but especially the seeds, are of value in local folklore medicine. Garcinia kola is used in treatment of numerous diseases, including gastric disorders, bronchial diseases, fever, malaria and is used to induce a stimulating and aphrodisiac effect. The plant is now attracting considerable interest as a possible source of pharmaceutically important drugs. Several different classes of compounds such as biflavonoids, benzophenones, benzofurans, benzopyran, vitamin E derivatives, xanthones, and phytosterols, have been isolated from G. kola, of which many appears to be found only in this species, such as garcinianin (found in seeds and roots), kolanone (fruit pulp, seeds, roots), gakolanone (stem bark), garcinoic acid, garcinal (both in seeds), garcifuran A and B, and garcipyran (all in roots). They showed a wide range of pharmacological activities (e.g. analgesic, anticancer, antidiabetic, anti-inflammatory, antimalarial, antimicrobial, hepatoprotective and neuroprotective effects), though this has only been confirmed in animal models. Kolaviron is the most studied compound and is perceived by many studies as the active principle of G. kola. However, its research is associated with significant flaws (e.g. too high doses tested, inappropriate positive control). Garcinol has been tested under better conditions and is perhaps showing more promising results and should attract deeper research interest (especially in the area of anticancer, antimicrobial, and neuroprotective activity). Human clinical trials and mechanism-of-action studies must be carried out to verify whether any of the compounds present in G. kola may be used as a lead in the drug development.

Effects of Lactobacillus acidophilus administration to anorexigenic neuropeptides and some biochemical parameters on rats fed with a high-fat diet

AIM

One of the rapidly rising global public health concern is obesity. Over the past three decades, the prevalence of obesity has doubled/tripled in several nations around the world, most likely as a result of urbanization, sedentary lifestyles, and increased intake of high-calorie processed foods. In this study, it was aimed to investigate the effects of Lactobacillus acidophilus administration on rats exposed to high-fat diet experimentally on anorexigenic peptides in the brain and some biochemical parameters in the serum.

METHODS

In the study, 4 different experimental groups were formed. Group 1 was designated as the control group and fed with a standard rat chow (SD). Group 2 was designated as the high-fat diet (HFD) fed group. Group 3 fed with SD and L. acidophilus probiotic administered. Group 4 fed with HFD and L. acidophilus probiotic administered. At the end of the experiment, leptin, serotonin, glucagon-like peptide-1 (GLP-1) levels were measured in the brain tissue and serum. Glucose, total cholesterol (TC), triglyceride (TG), total protein (TP), albumin, uric acid, aspartate transaminase (AST), alanine aminotransferase (ALT) levels were determined in the serum.

RESULTS

At the end of the study, it was found that there was an increase in body weight and body mass index in Group 2 compared to Group 1. It was determined that the levels of AST, ALT, TG, TC, glucose, leptin in the serum were significantly high (P < 0.05). The levels of GLP-1 and serotonin in the serum and in the brain were significantly low (P < 0.05). There was a significant decrease in TG and TC in Groups 3 and 4 compared to Group 2 (P < 0.05). The leptin hormone levels in serum and brain were significantly higher in Group 2 than in other groups (P < 0.05). GLP-1 and serotonin levels were found to be significantly low (P < 0.05). The leptin levels in the serum of Groups 3 and 4 decreased significantly compared to Group 2 (P < 0.05).

CONCLUSION

It was found that probiotic supplementation in high-fat diet had positive effects on anorexigenic peptides. It was concluded that L. acidophilus probiotic can be recommended as a food supplement in the treatment of obesity.

Potential cardioprotective effects of Amentoflavone in doxorubicin-induced cardiotoxicity in mice

Doxorubicin (DOX) is an available chemotherapeutic drug for treating various tumors. However, its effectiveness is limited by cardiotoxicity. Amentoflavone (AMF), a natural biflavonoid separated from Cycas thouarsii ethyl acetate fraction, displays promising anticancer, anti-inflammatory, and antioxidant effects. Thus, our research aims to explore whether AMF could boost cardioprotective effects against DOX cardiotoxicity and reveal the potential underlying mechanisms of cardioprotection. Mice were classified into four groups; Normal control, Untreated DOX group, and DOX groups treated with AMF (40 and 80 mg/kg, respectively) intraperitoneal injection daily for four days before doxorubicin administration and for additional three days following DOX administration to assess cardiotoxicity. Echocardiography showed that AMF 80 treated group was protected from DOX cardiotoxicity. Additionally, it alleviated histopathological structural alterations and effectively restored heart weight and body weight ratio. These effects were confirmed biochemically by a substantially reduced serum creatine kinase-MB (CK-MB) and aspartate aminotransferase (AST) levels. AMF effectively restored nuclear respiratory factor-1(NRF-1), mitochondrial transcription factor A (TFAM), and normalized heat shock protein - 27(HSP-27) expression levels compared to the DOX group. Moreover, AMF mitigated oxidative stress conditions and significantly suppressed NADPH oxidase (NOX) expression levels. It also showed significant anti-inflammatory effects via suppressing interleukin-6 (IL-6) expression and decreasing nuclear factor Kabba B (NF-κb) immune-staining. In addition, AMF markedly reduced FAS ligand (FASL) expression and p53 immune staining in cardiac tissue. This study is the first for the in vivo potential beneficial effects of AMF against acute DOX cardiotoxicity, possibly via exerting antioxidant, anti-inflammatory, and anti-apoptotic effects and restoring mitochondrial function.

Plant Metabolites as SARS-CoV-2 Inhibitors Candidates: In Silico and In Vitro Studies

Since it acquired pandemic status, SARS-CoV-2 has been causing all kinds of damage all over the world. More than 6.3 million people have died, and many cases of sequelae are in survivors. Currently, the only products available to most of the world’s population to fight the pandemic are vaccines, which still need improvement since the number of new cases, admissions into intensive care units, and deaths are again reaching worrying rates, which makes it essential to compounds that can be used during infection, reducing the impacts of the disease. Plant metabolites are recognized sources of diverse biological activities and are the safest way to research anti-SARS-CoV-2 compounds. The present study computationally evaluated 55 plant compounds in five SARS-CoV-2 targets such Main Protease (Mpro or 3CL or MainPro), RNA-dependent RNA polymerase (RdRp), Papain-Like Protease (PLpro), NSP15 Endoribonuclease, Spike Protein (Protein S or Spro) and human Angiotensin-converting enzyme 2 (ACE-2) followed by in vitro evaluation of their potential for the inhibition of the interaction of the SARS-CoV-2 Spro with human ACE-2. The in silico results indicated that, in general, amentoflavone, 7-O-galloylquercetin, kaempferitrin, and gallagic acid were the compounds with the strongest electronic interaction parameters with the selected targets. Through the data obtained, we can demonstrate that although the indication of individual interaction of plant metabolites with both Spro and ACE-2, the metabolites evaluated were not able to inhibit the interaction between these two structures in the in vitro test. Despite this, these molecules still must be considered in the research of therapeutic agents for treatment of patients affected by COVID-19 since the activity on other targets and influence on the dynamics of viral infection during the interaction Spro x ACE-2 should be investigated.

Effects of Resveratrol Against Induced Metabolic Syndrome in Rats: Role of Oxidative Stress, Inflammation, and Insulin Resistance

Metabolic syndrome (MS) is a serious health problem associated with an increase in risk factors for hepatic steatosis, which is the most common liver disease today. The goal of this study was to investigate the protective effects of resveratrol against metabolic alterations associated with a high-fat high-fructose diet (HFFD). Thirty-two male rats were randomly divided into four equal groups: control (cont.), metabolic syndrome (MS), resveratrol (Res), and metabolic syndrome treated with resveratrol (MS + Res). Resveratrol was administrated orally at a dose of 30 mg/kg·bw, daily. After 10 weeks, body weight, serum biochemical parameters, hepatic oxidative stress, inflammatory markers, as well as mRNA levels of hepatic genes related to lipid metabolism and insulin signaling were measured. In addition, the liver was examined histopathologically to detect lipid deposition. Increased body weight, hepatic dysfunction, dyslipidemia, hepatic insulin resistance, hepatic oxidative and inflammatory stress conditions, upregulation of mRNA expression level of sterol regulatory element binding protein 1-c (SREBP1-c), and downregulation of mRNA expression levels of peroxisome proliferated activated receptor alpha (PPARα) and insulin receptor substrate-2 (IR-S2) were all observed in the MS rats. Hepatic steatosis was confirmed by hematoxylin and eosin and Oil Red O staining. Administration of resveratrol reduced liver steatosis, oxidative stress, and inflammatory state. Also, it improved lipid profile as well as insulin sensitivity and reverted alterations in hepatic mRNA expression levels of the tested genes. Based on these findings, resveratrol could be proposed as a therapeutic approach for MS prevention.

AMPK/mTOR-driven autophagy & Nrf2/HO-1 cascade modulation by amentoflavone ameliorates indomethacin-induced gastric ulcer

Gastric ulcer (GU) is a worldwide gastrointestinal disorder associated with NSAID use. Recently, amentoflavone proved to be a potent autophagy modulator, antioxidant, anti-inflammatory, and anti-apoptotic agent. Eight-week-old male Wistar rats received amentoflavone orally for 14 days at 25, 50, or 100 mg/kg/day. On day 14 of treatment, GU was induced by a single oral instillation of 100 mg/kg indomethacin, one hour after the last treatment. Amentoflavone dose-dependently alleviated indomethacin-induced GU, as demonstrated by repression of gastric mucosa pathological manifestations (ulcer index, ulcer surface area, histopathological deviations, and score) and increased ulcer inhibition percentage. These protective effects were due to the enhancement of gastric mucosa autophagy, as demonstrated by increased levels of beclin-1, MAP1LC3B, and CTSD, and reduced expression of p62 (SQSTM1). In addition, amentoflavone modulated the AMPK/mTOR pathway by increasing p-AMPK and reducing mTORC1 levels. Moreover, it hindered the redox aberrations by reducing MDA level and enhancing SOD activity, GSH level, and Nrf2/HO-1 cascade. Furthermore, a decrease in caspase-3 levels, Bax/Bcl-2 ratio and an increase in Bcl-2 expression suggest inhibition of the apoptotic process. Additionally, amentoflavone suppressed gastric mucosal inflammation by decreasing IL-1β, TNF-α, IFN-γ levels, IL-4, IL-6 mRNA expressions and MPO activity, and increasing IL-10 mRNA expresion. Therefore, amentoflavone could consider a promising natural agent protecting against indomethacin-induced GU.

Biflavonoids: Important Contributions to the Health Benefits of Ginkgo (Ginkgo biloba L.)

Ginkgo (Ginkgo biloba L.) is one of the most distinctive plants, characterized by excellent resistance to various environmental conditions. It is used as an ornamental plant and is recognized as a medicinal plant in both traditional and Western medicine. Its bioactive potential is associated with the presence of flavonoids and terpene trilactones, but many other compounds may also have synergistic effects. Flavonoid dimers-biflavonoids-are important constituents of ginkgophytopharmaceuticals. Currently, the presence of 13 biflavonoids has been reported in ginkgo, of which amentoflavone, bilobetin, sciadopitysin, ginkgetin and isoginkgetin are the most common. Their role in plants remains unknown, but their bioactivity and potential role in the management of human health are better investigated. In this review, we have provided an overview of the chemistry, diversity and biological factors that influence the presence of biflavonoids in ginkgo, as well as their bioactive and health-related properties. We have focused on their antioxidant, anticancer, antiviral, antibacterial, antifungal and anti-inflammatory activities as well as their potential role in the treatment of cardiovascular, metabolic and neurodegenerative diseases. We also highlighted their potential toxicity and pointed out further research directions.

Amentoflavone-Enriched Selaginella rossii Warb. Suppresses Body Weight and Hyperglycemia by Inhibiting Intestinal Lipid Absorption in Mice Fed a High-Fat Diet

Many Selaginellaceae species are used as traditional medicines in Asia. This study is the first to investigate the anti-obesity and anti-diabetic effects of Selaginella rossii (SR) in high-fat diet (HFD)–fed C57BL/6J mice. Seven-day oral administration of ethanol extract (100 mg/kg/day) or ethyl acetate (EtOAc) extract (50 mg/kg/day) from SR improved oral fat tolerance by inhibiting intestinal lipid absorption; 10-week long-term administration of the EtOAc extract markedly reduced HFD-induced body weight gain and hyperglycemia by reducing adipocyte hypertrophy, glucose levels, HbA1c, and plasma insulin levels. Treatment with SR extracts reduced the expression of intestinal lipid absorption-related genes, including Cd36, fatty acid-binding protein 6, ATP-binding cassette subfamily G member 8, NPC1 like intracellular cholesterol transporter 1, and ATP-binding cassette subfamily A member 1. In addition, the EtOAc extract increased the expression of protein absorption–related solute carrier family genes, including Slc15a1, Slc8a2, and Slc6a9. SR extracts reduced HFD-induced hepatic steatosis by suppressing fatty acid transport to hepatocytes and hepatic lipid accumulation. Furthermore, amentoflavone (AMF), the primary compound in SR extracts, reduced intestinal lipid absorption by inhibiting fatty acid transport in HFD-fed mice. AMF-enriched SR extracts effectively protected against HFD-induced body weight gain and hyperglycemia by inhibiting intestinal lipid absorption.

Insights Into Amentoflavone: A Natural Multifunctional Biflavonoid

Amentoflavone is an active phenolic compound isolated from Selaginella tamariscina over 40 years. Amentoflavone has been extensively recorded as a molecule which displays multifunctional biological activities. Especially, amentoflavone involves in anti-cancer activity by mediating various signaling pathways such as extracellular signal-regulated kinase (ERK), nuclear factor kappa-B (NF-κB) and phosphoinositide 3-kinase/protein kinase B (PI3K/Akt), and emerges anti-SARS-CoV-2 effect via binding towards the main protease (Mpro/3CLpro), spike protein receptor binding domain (RBD) and RNA-dependent RNA polymerase (RdRp) of SARS-CoV-2. Therefore, amentoflavone is considered to be a promising therapeutic agent for clinical research. Considering the multifunction of amentoflavone, the current review comprehensively discuss the chemistry, the progress in its diverse biological activities, including anti-inflammatory, anti-oxidation, anti-microorganism, metabolism regulation, neuroprotection, radioprotection, musculoskeletal protection and antidepressant, specially the fascinating role against various types of cancers. In addition, the bioavailability and drug delivery of amentoflavone, the molecular mechanisms underlying the activities of amentoflavone, the molecular docking simulation of amentoflavone through in silico approach and anti-SARS-CoV-2 effect of amentoflavone are discussed.

Amentoflavone prevents ox-LDL-induced lipid accumulation by suppressing the PPARγ/CD36 signal pathway

The formation of fat-laden foam cells plays an important role in the initiation and progression of atherosclerosis (AS). Amentoflavone (AF) is found in various traditional Chinese medicines, such as ginkgo biloba, which are used to treat cardiovascular diseases (CVDs). We aimed to explore the potential effects and mechanisms of AF on lipid accumulation, and its possible application in atherosclerotic cardiovascular disease (ASCVD). Cellular models of lipid accumulation were established by treatment of HUASMCs and THP-1 cells with oxidized low-density lipoprotein (ox-LDL). Cell viability, lipid accumulation, and ox-LDL uptake were assessed. Small interfering RNAs (siRNAs) and overexpression plasmids were used to reveal the hierarchical correlations of regulatory pathways. AF reduced the lipid accumulation and ox-LDL uptake induced by ox-LDL, and reduced the expression levels of cluster of differentiation 36 (CD36) and peroxisome proliferator-activated receptor gamma (PPARγ) proteins, while the expression level of ATP binding cassette subfamily A member 1 (ABCA1) increased. Knockdown of PPARγ or CD36 with siRNAs prevented ox-LDL-induced lipid accumulation. Overexpression of CD36 or PPARγ promoted the lipid accumulation induced by ox-LDL and eliminated the effect of AF on ox-LDL-induced lipid accumulation. Overall, AF prevents ox-LDL-induced lipid accumulation by suppressing the PPARγ/CD36 signaling pathway.

The effects of two types of Western diet on the induction of metabolic syndrome and cardiac remodeling in obese rats

Metabolic syndrome (MetS) include obesity as a critical feature and is strongly associated with risk of cardiovascular disease (CVD). Insights into mechanisms involved in the pathophysiology of these clinical manifestations are essential for the development of therapeutic strategies. Thus, Western diets (WD) have been widely employed in diet-induced obesity (DIO) model. However, there are variations in fat and sugar proportions of such diets, making comparisons challenging. We aimed to assess the impact of two types of the WD on metabolic status and cardiac remodeling, to achieve a DIO model that better mimics the human pathogenesis of MetS-induced CVD. Male Wistar rats were distributed into three groups: control diet, Western diet fat (WDF), and Western diet sugar (WDS) for 41 weeks. Metabolic and inflammatory parameters and cardiac changes were characterized. WDF and WDS feeding promoted higher serum triglycerides, glucose intolerance, and insulin resistance, while just WDF presented inflammation in adipose tissue. WDF-fed rats showed increased catalase activity and malondialdehyde (MDA) and carbonyl protein levels, suggesting cardiac oxidative stress, while WDS-fed rats only raised MDA. Both WD equally elevated protein expressions involved in lipid metabolism, but only WDF downregulated the glycolysis pathway. Furthermore, the mechanical myocardial function was impaired in obese rats, being more relevant in WDF. In conclusion, both WD effectively triggered MetS features, although inflammation was detected just on the WDF-fed animals. Moreover, the WDF promoted a more pronounced functional, metabolic, and oxidative cardiac disorder, suggesting to be an adequate model for studying CVD in the scenario of MetS.

Effects of aerobic exercise training and açai supplementation on cardiac structure and function in rats submitted to a high-fat diet

This study evaluated the effect of aerobic exercise training (AET) and supplementation with açai on cardiac structure and function in rats submitted to a high-fat diet. Two-month old Fischer male rats were divided into 5 groups: Control (C), High-fat Diet (H), High-fat Diet + Açai (HA), High-fat Diet + AET (HT), High-fat Diet + Açai + AET (HAT). The high-fat diet had 21.8% lard and 1% cholesterol (H and HT), or supplemented with 1% lyophilized açai pulp (HA and HAT). The HT and HAT groups performed AET on a treadmill (5 days/week, 1 h/day, 60% of the maximum running speed) for 8 weeks. Exercise tolerance test were performed, and adiposity index calculated. After euthanasia, the left ventricle (LV) was dissected and processed for histological, single myocyte intracellular calcium ([Ca²⁺]_i) transient and contractility, oxidative stress and gene expression analysis. AET improved running capacity and reduced the adiposity index. Both AET and açai supplementation inhibited the increase in the LV collagen content, the deleterious effects on the [Ca²⁺]_i transient and contractility in cardiomyocytes and the increment in oxidative stress, caused by the consumption of a high-fat diet. Aerobic exercise training and açai supplementation can mitigate damage caused by high-fat diet in cardiac structure and function, though the combination of treatments had no additional effects.

The total flavonoids from Selaginella tamariscina (beauv.) Spring improve glucose and lipid metabolism in db/db mice

Objectives

This study aimed to investigate the glucose and lipid metabolism improving effect of the total flavonoids from Selaginella tamariscina (Beauv.) Spring (TFST) on db/db mice, and to study its mechanism of action.

Materials and Methods

The db/db mice were divided into 5 groups: the normal group (NC), the diabetic group (DM), the gliclazide group (GZ), the DM+TFST (110 mg/kg), and the DM+TFST (220 mg/kg). The body weight, blood glucose, INS, GC, TC, TG, LDL, and HDL were detected. HE staining was used to observe the liver and pancreas. Urine was tested by UPLC-QTOF-MS to study the metabolic differences of each group, coupled with SIMCA-P13.0 for PCA and OPLS-DA analysis, to identify potential biomarkers, find the metabolic pathway. Western blot was used to examine liver tissue of mice for studying effect of TFST on the PPAR-γ/PI3K/GLU4 pathway.

Results

TFST can reduce the weight and levels of TC, TG, and LDL-C, increase the level of GC in blood, and reduce the fat accumulation and inflammation in the liver, and repair the islet cell. 13 biomarkers were identified, they are mainly involved in amino acid metabolism, and purine and pyrimidine metabolism. The results of Western blot show TFST can improve the utilization rate of GLU4 by regulating PPAR-γ and PI3K expression in the liver of db/db mice.

Conclusion

TFST can improve glucose and lipid metabolism of DM, which relates to regulation of the PPAR-γ/PI3K/GLU4 signaling pathway, and affect the amino acid metabolism, purine, and pyrimidine metabolism.

Mitigation of renal inflammation and endoplasmic reticulum stress by vildagliptin and statins in high-fat high-fructose diet-induced insulin resistance and renal injury in rats

Dyslipidemia and insulin resistance in obesity can lead to lipotoxicity and cellular damage. Renal lipotoxicity in association with an impairment of lipid metabolism induces renal damage through the activation of inflammation, ER stress, fibrosis and apoptosis. We investigated the effects of a combination treatment of the DPP-4 inhibitor vildagliptin and atorvastatin on renal lipotoxicity related to renal dysfunction and injury in a high-fat high-fructose diet (HFF)-induced insulin resistant condition. Male Wistar rats were fed on a high-fat diet and were given drinking water with 10% fructose for 16 weeks. After that, rats were divided into: no treatment (HFF), treatment with vildagliptin, atorvastatin and vildagliptin plus atorvastatin for 4 weeks. The results demonstrated that the combination treatment prominently improved insulin resistance, dyslipidemia and kidney morphological changes induced by HFF. These changes correlated well with the increased expression of nephrin and podocin and decreased urine protein. Notably, the combined treatment produced greater improvement in renal lipid metabolism through increasing fatty acid oxidation with the decreases in fatty acid transporters and fatty acid synthesis, thereby reducing renal lipid accumulation in HFF rats. The reduction in renal lipotoxicity via diminishing renal inflammation, ER stress, fibrosis and apoptosis was also more significant in the combined treatment group than in the other groups in which the drug was used as a monotherapy. In conclusion, the combination therapy produced synergistic beneficial effects on metabolic parameters, lipid metabolism and accumulation related to renal lipid accumulation-induced lipotoxicity and kidney injury in the HFF-induced insulin resistant model with improved outcomes.

Clinical Prescription-Protein-Small Molecule-Disease Strategy (CPSD), A New Strategy for Chinese Medicine Development: A Case Study in Cardiovascular Diseases

Chinese medicine is a national treasure that has been passed down for thousands of years in China. According to the statistics of the World Health Organization, there are currently four billion people in the world who use Chinese medicine to treat diseases, accounting for 80% of the world's total population. However, the obscurity of its theory, its unmanageable quality, its complex compositions, and the unknown effective substances and mechanisms are great obstacles to the internationalization of Chinese medicine. Here, we propose a new strategy for the development of Chinese medicine: the clinical prescription (C)-protein (P)-small-molecule (S)-disease (D) strategy, namely the CPSD strategy. The strategy uses clinical prescriptions as the source of medicine and uses computer simulation technology to find small-molecule drugs targeting therapeutic proteins for treating specific diseases so as to deepen awareness of the value of Chinese medicine. At the same time, this article takes cardiovascular drug development as an example to introduce the application of CPSD, which will be instrumental in the further development, modernization, and internationalization of Chinese medicine.

Beneficial Effect of a Multistrain Synbiotic Prodefen® Plus on the Systemic and Vascular Alterations Associated with Metabolic Syndrome in Rats: The Role of the Neuronal Nitric Oxide Synthase and Protein Kinase A

A high fat diet (HFD) intake is crucial for the development and progression of metabolic syndrome (MtS). Increasing evidence links gut dysbiosis with the metabolic and vascular alterations associated with MtS. Here we studied the use of a combination of various probiotic strains together with a prebiotic (synbiotic) in a commercially available Prodefen® Plus. MtS was induced by HFD (45%) in male Wistar rats. Half of the MtS animals received Prodefen® Plus for 4 weeks. At 12 weeks, we observed an increase in body weight, together with the presence of insulin resistance, liver steatosis, hypertriglyceridemia and hypertension in MtS rats. Prodefen® Plus supplementation did not affect the body weight gain but ameliorated all the MtS-related symptoms. Moreover, the hypertension induced by HFD is caused by a diminished both nitric oxide (NO) functional role and release probably due to a diminished neuronal nitric oxide synthase (nNOS) activation by protein kinase A (PKA) pathway. Prodefen® Plus supplementation for 4 weeks recovered the NO function and release and the systolic blood pressure was returned to normotensive values as a result. Overall, supplementation with Prodefen® Plus could be considered an interesting non-pharmacological approach in MtS.

Temporal Measures in Cardiac Structure and Function During the Development of Obesity Induced by Different Types of Western Diet in a Rat Model

Obesity is recognized worldwide as a complex metabolic disorder that has reached epidemic proportions and is often associated with a high incidence of cardiovascular diseases. To study this pathology and evaluate cardiac function, several models of diet-induced obesity (DIO) have been developed. The Western diet (WD) is one of the most widely used models; however, variations in diet composition and time period of the experimental protocol make comparisons challenging. Thus, this study aimed to evaluate the effects of two different types of Western diet on cardiac remodeling in obese rats with sequential analyses during a long-term follow-up. Male Wistar rats were distributed into three groups fed with control diet (CD), Western diet fat (WDF), and Western diet sugar (WDS) for 41 weeks. The animal nutritional profile and cardiac histology were assessed at the 41st week. Cardiac structure and function were evaluated by echocardiogram at four different moments: 17, 25, 33, and 41 weeks. A noninvasive method was performed to assess systolic blood pressure at the 33rd and 41st week. The animals fed with WD (WDF and WDS) developed pronounced obesity with an average increase of 86.5% in adiposity index at the end of the experiment. WDF and WDS groups also presented hypertension. The echocardiographic data showed no structural differences among the three groups, but WDF animals presented decreased endocardial fractional shortening and ejection fraction at the 33rd and 41st week, suggesting altered systolic function. Moreover, WDF and WFS animals did not present hypertrophy and interstitial collagen accumulation in the left ventricle. In conclusion, both WD were effective in triggering severe obesity in rats; however, only the WDF induced mild cardiac dysfunction after long-term diet exposure. Further studies are needed to search for an appropriate DIO model with relevant cardiac remodeling.

Probiotics Improve Chemerin Levels and Metabolic Syndrome Parameters in Obese Rats

Background

Chemerin is a recently discovered adipokine that plays a role in adipocyte metabolism. It is a novel chemoattractant adipokine whose expression and secretion are increased by adipogenesis.

Aims

To evaluate the effects of probiotic supplementation on chemerin level, inflammation, and metabolic syndrome components in obese Wistar rats.

Study Design

Animal experiment.

Methods

We divided the experimental animals into three groups, each consisting of eight rats. Group 1 was the control group. Group 2 was the experimentally obese group, in which rats were fed with a high-fat diet. Group 3 was the obese intervention group, in which rats were supplemented with probiotics after obesity induction.

Results

At the end of the study, a statistically significant difference was found between the groups in final weights, weight changes, and body mass index values (p<0.05). Weight gain was 34.12±3.70 g in group 3 post-probiotic supplementation and 53.25±8.35 g in group 2 (p<0.05). Obese rats showed increased levels of fasting plasma glucose, insulin, insulin resistance (homeostatic model assessment-insulin resistance), total cholesterol, low-density lipoprotein cholesterol, inflammatory markers, and leptin compared to those in the control group. Chemerin levels were 14.31±13.34 ng/mL in group 2 and 2.67±2.42 ng/mL in group 3 (p<0.05).

Conclusion

Probiotic supplementation (group 3) reduced weight gain, and there were positive effects on the levels of fasting plasma glucose, insulin, homeostatic model assessment-insulin resistance, triglycerides, inflammatory markers, leptin, and chemerin.

Melatonin protects the heart and endothelium against high fructose corn syrup consumption-induced cardiovascular toxicity via SIRT-1 signaling

High fructose corn syrup (HFCS) has been shown to cause cardiovascular toxicity via oxidative stress and inflammation. The aim of this study is to demonstrate the protective effects of melatonin (MLT) against HFCS-induced endothelial and cardiac dysfunction via oxidative stress and inflammation. Thirty-two Sprague Dawley male rats were distributed into three groups as control, HFCS, and HFCS + MLT. HFCS form F55 was prepared as 20% fructose syrup solution and given to the rats through drinking water for 10 weeks, and MLT administrated 10 mg/kg/day orally for last 6 weeks in addition to F55. After decapitation, blood and half of the heart samples were collected for biochemical analysis and other half of the tissues for histopathological and immunohistochemical analysis. Aspartate transaminase, creatine kinase MB, lactate dehydrogenase, total oxidant status and oxidative stress index, and caspase-3 levels increased and total antioxidant status levels decreased significantly in HFCS group. MLT treatment reversed all these parameters. Histopathologically, hyperemia, endothelial cell damage and increased levels of angiogenin, C-reactive protein, inducible nitric oxide synthase, myeloperoxidase and decreased sirtuin-1 (SIRT-1) expressions were observed in HFCS group. MLT ameliorated all these changes. MLT has an anti-inflammatory, antioxidant, antiapoptotic effects on HFCS-induced cardiovascular toxicity through enhancing the expression of SIRT-1.

Increased systolic blood pressure associated with hypertriglyceridemia in female Sprague-Dawley rats

The effect of hyperlipidemia on the cardiovascular system is uncertain in females. The aim of the present study was to determine whether administration of a lipogenic diet alters cardiovascular parameters in female rats. Fifty female Sprague-Dawley rats were assigned into 2 groups of rats receiving a standard or a high-fat, high-sucrose diet (HFHS) for 6 weeks (n = 25 per group). Body mass, blood lipids concentrations, triglycerides clearance, blood pressures (BPs), systolic and diastolic functions, as well as vascular reactivity were assessed at the end of the diet intervention. At termination, body mass was similar between the 2 groups. Fasting blood triglycerides concentration (BTG) was greater in the HFHS group. Triglycerides clearance was impaired in the HFHS group. High-density lipoprotein (HDL) cholesterol concentration was lower in the HFHS group. The early-to-late diastolic filling velocity ratio (E/A) was lower in the HFHS group and negatively associated with BTG. The sensitivity (EC₅₀) of mesenteric arteries to phenylephrine was greater in HFHS and was negatively associated with BTG, but not HDL. Systolic BP was higher in the HFHS group and was positively associated with BTG and HDL. The association between systolic BP and BTG was independent of other lipids measured. In conclusion, hypertriglyceridemia may have increased resistance arteries responsiveness to alpha-agonist and systolic BP in female rats.

Peel flour of Passiflora edulis Var. Flavicarpa supplementation prevents the insulin resistance and hepatic steatosis induced by low-fructose-diet in young rats

The increase in fructose consumption in the last decades has an important correlation with the growth of overweight population. Fructose is a monosaccharide found in fruits, vegetables and honey, however, it is widely used in processed food and beverages such as sweeteners. This monosaccharide is metabolized in the liver, so it can produce glucose, lactate, triglycerides, free fatty acids and uric acid, which are responsible for negative effects on the liver and extrahepatic tissues. One effect of the high consumption of fructose is the resistance to Insulin, which appears to be an important issue in the development of metabolic abnormalities observed in animals that were subjected to a high fructose diet. The population and, consequently, the market search for natural sources to manage metabolic abnormalities is increasing, but, adequate scientific proof still is necessary. The Passiflora edulis peel flour (PEPF) is a byproduct of the juice industry, and, represents an important source of fiber and bioactive compounds. The present study investigates the PEPF supplementation (30%) effects on insulin sensitivity, adiposity and metabolic parameters in young rats that were given beverages enriched with 10% of fructose for 8 weeks. Fructose intake induced insulin resistance, increased serum triglycerides levels, growth of fat deposits in the liver and widening of the diameter of adipocytes. In contrast, the group that received PEPF did not present such abnormalities, which could be related to the presence of fiber or bioactive compounds (phenolics compounds, e.g., caffeic acid and isoorientin) in its composition, as identified by analytical methods. Thus, for the first time, it has been demonstrated that PEPF supplementation prevents insulin resistance and hepatic steatosis induced by low-fructose-diet in young rats.