α-Amyrin attenuates high fructose diet-induced metabolic syndrome in rats

Delphinidin or α-amyrin attenuated liver steatosis and metabolic disarrangement in rats fed a high-fat diet

Non-alcoholic fatty liver disease (NAFLD) is a liver pathology concomitant with metabolic disarrangement. This study assessed the therapeutic impacts of delphinidin, an anthocyanin, or α-amyrin, a pentacyclic triterpenoid, on NAFLD in rats and the underlying mechanisms involved. NAFLD was established by feeding a high-fat diet (HFD) for 10 weeks, either alone or in combination with delphinidin (40 mg/kg, oral) or α-amyrin (20 mg/kg, oral). Delphinidin or α-amyrin ameliorated the metabolic and histopathological perturbations induced by HFD. These compounds markedly attenuated NAFLD-induced hepatic steatosis, as evidenced by a substantial decrease in body weight, insulin resistance, and liver and adipose tissue indices. Alongside normalization of the atherogenic index, both improved HFD-mediated abnormalities in serum lipids, liver enzymes, leptin, and ghrelin levels. Moreover, their intervention activated the NFE2 like bZIP transcription factor 2 and heme oxygenase 1 pathways and abrogated HFD-triggered activation of mitogen-activated protein kinase 1 signaling. These remedies inhibited hepatic apoptosis and modulated the gene expression of lipogenic enzymes. Furthermore, histological analysis corroborated the suppression of lipid accumulation and amelioration of hepatic architecture in the treated rats. Our findings highlight the hepatoprotective value of delphinidin or α-amyrin against NAFLD and related metabolic diseases through their insulin-sensitizing, anti-inflammatory, antioxidant, and antiapoptotic effects.

Molecular Insight into the Pharmacological Potential of Clerodendrum minahassae Leaf Extract for Type-2 Diabetes Management Using the Network Pharmacology Approach

Background and Objectives: The increasing occurrence and prevalence of type-2 diabetes mellitus (T2DM) have led to a growing interest in researching available treatment alternatives. Clerodendrum minahassae, a native plant species of North Sulawesi, has been a focus of ethnopharmacological studies due to its significance contributions to drug development, particularly its potential antidiabetic properties. This study investigated the pharmacological potential of Clerodendrum minahassae (CM) leaf extract for managing type-2 diabetes (T2DM) using a network pharmacology approach. Materials and Methods: Active compounds were extracted from CM leaves, and their interactions with target proteins in T2DM were explored through various in silico analyses. Results: SAR analysis using Way2Drug Pass Online identified 29 bioactive CM leaf extract compounds with promise as T2DM treatments. Additionally, 26 of these met Ro5 criteria for favorable drug-likeness. Most compounds exhibited positive pharmacodynamic and pharmacokinetic profiles, with 22 considered safe, while 7 posed potential toxicity risks when ingested individually. CM leaf extract targeted 60 T2DM-related proteins, potentially affecting T2DM via cytokine regulation, particularly in proteins linked to metabolic processes, cellular response to angiotensin, and the sphingosine-1-phosphate signaling pathway. The network pharmacology analysis identified five genes targeted by CM leaf extract, namely, STAT3, MAPK1, ESR1, PIK3R1, and NFKB1. Among these genes, PIK3R1's interaction with the insulin receptor (INSR) positions it as a crucial candidate gene due to its pivotal role in insulin signal transduction during T2DM development. Conclusions: This research sheds light on the therapeutic potential of CM leaf extract for treating T2DM. This potential is attributed to the diverse array of bioactive compounds present in the extract, which have the capacity to interact with and inhibit proteins participating in the insulin signal transduction pathway crucial for the progression of T2DM. The findings of this study may open up possibilities for future applications of CM leaf extract in the development of novel T2DM treatments.

Study on the Potential Mechanism of Tonifying Kidney and Removing Dampness Formula in the Treatment of Postmenopausal Dyslipidemia Based on Network Pharmacology, Molecular Docking and Experimental Evidence

BACKGROUND

Management of menopausal dyslipidemia is the main measure to reduce the incidence of cardiovascular disease in postmenopausal women. Tonifying Kidney and Removing Dampness Formula (TKRDF) is a traditional Chinese medicine (TCM) formula that ameliorates dyslipidemia in postmenopausal women. This study applied network pharmacology, molecular docking, and in vitro and in vitro experiments to investigate the underlying mechanism of TKRDF against postmenopausal dyslipidemia.

METHODS

Network pharmacology research was first conducted, and the active compounds and targets of TKRDF, as well as the targets of postmenopausal dyslipidemia, were extracted from public databases. Protein-protein interaction (PPI), Gene Ontology (GO), and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway analysis were used to identify the potential targets and signaling pathways of TKRDF in postmenopausal dyslipidemia. Molecular docking was then performed to evaluate the combination of active compounds with principal targets. Finally, an ovariectomized rat model was used for the in vivo experiment and alpha mouse liver 12 (AML12) cells treated with palmitic acid were used for the in vitro experiments to provide further evidence for the research.

RESULTS

Based on network pharmacology analysis, we obtained 78 active compounds from TKRDF that acted on 222 targets of postmenopausal dyslipidemia. The analysis results indicated that IL6, TNF, VEGFA, AKT1, MAPK3, MAPK1, PPARG and PIK3CA, etc., were the potentially key targets, and the PI3K/AKT signaling pathway was the possibly crucial pathway for TKRDF to treat postmenopausal dyslipidemia. Molecular docking suggested that the active compounds have good binding activity with the core targets. The in vivo and in vitro experiments demonstrated that TKRDF ameliorates postmenopausal dyslipidemia by regulating hormone levels, inhibiting inflammation, promoting angiogenesis and inhibiting lipid synthesis, which appear to be related to TKRDF's regulation of the ERK1/2 and PI3K/AKT signaling pathways.

CONCLUSION

This study clarified the active ingredients, potential targets, and molecular mechanisms of TKRDF for treating postmenopausal dyslipidemia. It also provided a feasible method to uncover the scientific basis and therapeutic mechanism for prescribing TCM in the treatment of diseases.

Anticancer Potential of Betulonic Acid Derivatives

Clinical trials have evidenced that several natural compounds, belonging to the phytochemical classes of alkaloids, terpenes, phenols and flavonoids, are effective for the management of various types of cancer. Latest research has proven that natural products and their semisynthetic variants may serve as a starting point for new drug candidates with a diversity of biological and pharmacological activities, designed to improve bioavailability, overcome cellular resistance, and enhance therapeutic efficacy. This review was designed to bring an update regarding the anticancer potential of betulonic acid and its semisynthetic derivatives. Chemical derivative structures of betulonic acid including amide, thiol, and piperidine groups, exert an amplification of the in vitro anticancer potential of betulonic acid. With the need for more mechanistic and in vivo data, some derivatives of betulonic acids may represent promising anticancer agents.

Bioactive Triterpenes of Protium heptaphyllum Gum Resin Extract Display Cholesterol-Lowering Potential

Hypercholesterolemia is one of the major causes of cardiovascular disease, the risk of which is further increased if other forms of dyslipidemia occur. Current therapeutic strategies include changes in lifestyle coupled with drug administration. Statins represent the most common therapeutic approach, but they may be insufficient due to the onset of resistance mechanisms and side effects. Consequently, patients with mild hypercholesterolemia prefer the use of food supplements since these are perceived to be safer. Here, we investigate the phytochemical profile and cholesterol-lowering potential of Protium heptaphyllum gum resin extract (PHE). Chemical characterization via HPLC-APCI-HRMS² and GC-FID/MS identified 13 compounds mainly belonging to ursane, oleanane, and tirucallane groups. Studies on human hepatocytes have revealed how PHE is able to reduce cholesterol production and regulate the expression of proteins involved in its metabolism. (HMGCR, PCSK9, LDLR, FXR, IDOL, and PPAR). Moreover, measuring the inhibitory activity of PHE against HMGR, moderate inhibition was recorded. Finally, molecular docking studies identified acidic tetra- and pentacyclic triterpenoids as the main compounds responsible for this action. In conclusion, our study demonstrates how PHE may be a useful alternative to contrast hypercholesterolemia, highlighting its potential as a sustainable multitarget natural extract for the nutraceutical industry that is rapidly gaining acceptance as a source of health-promoting compounds.

Administration of ursolic acid to new-born pups prevents dietary fructose-induced non-alcoholic fatty liver disease in Sprague Dawley rats

Overconsumption of fructose time dependently induces the development of non-alcoholic fatty liver disease (NAFLD). We investigated whether ursolic acid (UA) intake by new-born rats would protect against fructose-induced NAFLD. One hundred and seven male and female Sprague Dawley rat pups were randomly grouped and gavaged (10 ml/kg body weight) with either 0.5% dimethylsulphoxide (vehicle control), 0.05% UA, 50% fructose mixed with UA (0.05%) or 50% fructose alone, from postnatal day 6 (P6) to P20. Post-weaning (P21-P69), the rats received normal rat chow (NRC) and water to drink. On P70, the rats in each group were continued on water or 20% fructose to drink, as a secondary high fructose diet during adulthood. After 8 weeks, body mass, food and fluid intake, circulating metabolites, visceral adiposity, surrogate markers of liver function and indices of NAFLD were determined. Food intake was reduced as a result of fructose feeding in both male and female rats (p < 0.0001). Fructose consumption in adulthood significantly increased fluid intake and visceral adiposity in female rats (p < 0.05) and had no apparent effects in male rats (p > 0.05). In both sexes of rats, fructose had no significant (p > 0.05) effects on body mass, circulating metabolites, total calorie intake and surrogate markers of hepatic function. Fructose consumption in both early life and adulthood in female rats promoted hepatic lipid accumulation (p < 0.001), hypertrophy, microvesicular and macrovesicular steatosis (p < 0.05). Early-life UA intake significantly (p < 0.001) reduced fructose-induced hepatic lipid accumulation in both male and female rats. Administration of UA during periods of developmental plasticity shows prophylactic potential against dietary fructose-induced NAFLD.

Diagnostic Criteria for Metabolic Syndrome in Diet-Induced Rodent Models: A Systematic Review

BACKGROUND

Thousands of publications in recent years have addressed the induction of metabolic syndrome (MetS) in rodents. However, the criteria and the reference values for diagnosing this disease have not been defined.

OBJECTIVE

Our main objective was to carry out a systematic review to gather evidence about the criteria for biochemical and anthropometric parameters in which scientific studies have relied on to report that rats developed MetS from a previous dietary manipulation.

METHODS

We compiled characteristics and findings of diet-induced MetS with high-fat, high-carbohydrate, high-fat/high-carbohydrates, and cafeteria diet from PubMed and Science Direct databases published in the last 5 years.

RESULTS

The results on the principal determinants for the syndrome, published in the reviewed articles, were chosen to propose reference values in the rat models of food induction.

CONCLUSION

The values obtained will serve as reference cut-of points in the development of the disease; in addition, the compilation of data will be useful in planning and executing research protocols in animal models.

Effects of TNF-α antagonist infliximab on fructose-induced metabolic syndrome in rats

Public health issues have been raised regarding fructose toxicity and its serious metabolic disorders. Deleterious effects of high fructose intake on insulin sensitivity, body weight, lipid homeostasis have been identified. The new millennium has witnessed the emergence of a modern epidemic, the metabolic syndrome (MS), in approximately 25% of the world's adult population. The current study aimed to investigate the effect of the TNF-α antagonist infliximab on fructose-induced MS in rats. Rats were administered fructose (10%) in drinking water for 12 weeks to induce the experimental MS model. infliximab (5 mg/kg) was injected once weekly intraperitoneally starting on the 13th week for 4 weeks. Increase in body weight, blood glucose level, serum triglycerides (TGs), adiponectin level and blood pressure were present in MS rats. They also prompted increases in serum of leptin, TNF-α, and malondialdehyde (MDA) levels. Treatment with infliximab did not affect body weight, hyperglycemia or hypertension, but decreased serum TGs and increased serum HDL-c levels. Infliximab also decreased adiponectin levels. Surprisingly, infliximab increased MDA above its value in the MS group. These results reflect the fact that infliximab affects the manifestations of MS in rats. Though infliximab reduced TGs, increased HDL-c levels, reversed adiponectin resistance occurred by fructose, the drug failed to combat MS-mediated hyperglycemia, hypertension, and elevated MDA above the insult.

Health benefits of 4,4-dimethyl phytosterols: an exploration beyond 4-desmethyl phytosterols

4,4-Dimethyl phytosterols possess two methyl groups at the carbon-4 atom of the aliphatic A-ring. The methyl groups are crucial for the molecular recognition of endogenous and exogenous bioactive compounds. Phytosterols have received worldwide attention owing to their recognized health benefits. However, 4,4-dimethyl phytosterols are less appreciated. Recent research studies revealed that 4,4-dimethyl phytosterols exert numerous beneficial effects on disease prevention, and are particularly involved in the endogenous cannabinoid system (ECS). The purpose of this review is to summarize and highlight the currently available information regarding the structures and sources of 4,4-dimethyl phytosterols, and to provide detailed preclinical studies performed to evaluate their potential for treating various diseases. Future research on 4,4-dimethyl phytosterols is warranted to confirm their relationship with the ECS, and to elucidate the mechanism directly toward clinical trials.

Dietary high calories from sunflower oil, sucrose and fructose sources alters lipogenic genes expression levels in liver and skeletal muscle in rats

INTRODUCTION AND OBJECTIVES

The objectives of this study were to investigate the underlying mechanism of PPARα, LXRα, ChREBP, and SREBP-1c at the level of gene and protein expression with high-energy diets in liver and skeletal muscle.

MATERIALS AND METHODS

Metabolic changes with consumption of high fat (Hfat), high sucrose (Hsuc) and high fructose (Hfru) diets were assessed. Levels of mRNA and protein of PPARα, LXRα, ChREBP, and SREBP-1c were investigated. Body weight changes, histological structure of liver and plasma levels of some parameters were also examined.

RESULTS

In Hfru group, body weights were higher than other groups (P<0.05). In liver, LXRα levels of Hsuc and Hfru groups were upregulated as 1.87±0.30 (P<0.05) and 2.01±0.29 (P<0.01). SREBP-1c levels were upregulated as 4.52±1.25 (P<0.05); 4.05±1.11 (P<0.05) and 3.85±1.04 (P<0.05) in Hfat, Hsuc, and Hfru groups, respectively. In skeletal muscle, LXRα and SREBP-1c were upregulated as 1.77±0.30 (P<0.05) and 2.71±0.56 (P<0.05), in the Hfru group. Protein levels of ChREBP (33.92±8.84ng/mg protein (P<0.05)) and SREBP-1c (135.16±15.57ng/mg protein (P<0.001)) in liver were higher in Hfru group. In skeletal muscle, LXRα, ChREBP and SREBP-1c in Hfru group were 6.67±0.60, 7.11±1.29 and 43.17±6.37ng/mg, respectively (P<0.05; P<0.01; P<0.05). The rats in Hfru group had the most damaged livers.

CONCLUSION

Besides liver, fructose consumption significantly effects skeletal muscle and leads to weight gain, triggers lipogenesis and metabolic disorders.

Pentacyclic triterpenes: New tools to fight metabolic syndrome

BACKGROUND

Metabolic syndrome is a combination of dysregulated cardiometabolic risk factors characterized by dyslipidemia, impaired glucose tolerance, insulin resistance, inflammation, obesity as well as hypertension. These factors are tied to the increased risk for type-II diabetes and cardiovascular diseases including myocardial infarction in patients with metabolic syndrome.

PURPOSE

To review the proposed molecular mechanisms of pentacyclic triterpenes for their potential use in the metabolic syndrome.

METHODS

PubMed, Science Direct, and Google Scholar database were searched from commencement to April 2018. Following keywords were searched in the databases with varying combinations: "metabolic syndrome", "pentacyclic triterpenes", "transcription factors", "protein kinase", "lipogenesis", "adipogenesis", "lipolysis", "fatty acids", "gluconeogenesis", "cardiovascular", "mitochondria", "oxidative stress", "pancreas", "hepatic cells", "skeletal muscle", "3T3-L1", "C2C12", "obesity", "inflammation", "insulin resistance", "glucose uptake", "clinical studies" and "bioavailability".

RESULTS

Pentacyclic triterpenes, such as asiatic acid, ursolic acid, oleanolic acid, 18β-glycyrrhetinic acid, α,β-amyrin, celastrol, carbenoxolone, corosolic acid, maslinic acid, bardoxolone methyl and lupeol downregulate several metabolic syndrome components by regulating transcription factors, protein kinases and enzyme involved in the adipogenesis, lipolysis, fatty acid oxidation, insulin resistance, mitochondria biogenesis, gluconeogenesis, oxidative stress and inflammation.

CONCLUSION

In vitro and in vivo studies suggests that pentacyclic triterpenes effectively downregulate various factors related to metabolic syndrome. These phytochemicals may serve as promising candidates for clinical trials for the management of metabolic syndrome.

Pharmacological effects of the isomeric mixture of alpha and beta amyrin from Protium heptaphyllum: a literature review

Protium heptaphyllum Aubl. belongs to the Burseraceae family. It is commonly called 'almecegueira' and is known to produce an amorphous resin which has constituents such as α- and β-amyrin, taraxastan-3-oxo-20-ol and sitostenonein. The α- and β-amyrin from P. heptaphyllum have pharmacological activities in several systems, such as central and peripheral nervous system, gastrointestinal tract and immunological system. In this study, our objective was to review pharmacological activities and to gather more information on the mixture of α- and β-amyrin obtained from P. heptaphyllum to guide future preclinical and clinical studies using this compound. This review consisted of searches performed using scientific databases such as PubMed, SciELO, LILACS, SciFinder and Science Direct. Some uses of α- and β-amyrin have been partially confirmed by previous studies demonstrating analgesic, anti-inflammatory, anticonvulsant, antidepressive, gastroprotective, hepatoprotective, antipancreatitic, anticholytic, antihyperglycemic and hypolipidemic effects. It is noteworthy that there are no α- and β-amirin toxicity tests described in the literature as recommended in the international guidelines, and such tests are one of the research stages to proceed in clinical and preclinical trials if this compound was to be used.

Inhibition of adiposity and related metabolic disturbances by polyphenol-rich extract of Boswellia serrata gum through alteration of adipo/cytokine profiles

BACKGROUND

The role of proinflammatory cytokines in adiposity is well established. The anti-inflammatory and antihyperglycemia effects of Boswellia serrata (B. Serrata) gum have been demonstrated by many investigators. The present study aimed to investigate the anti-obesity potential of B. serrata extract.

METHODS

The effects of B. serrata extract on lipase activity and acute food intake were investigated. The present study aimed to investigate the anti-obesity potential of B. serrata extract. The effects on lipase activity and acute food intake were investigated. Body weight changes, biochemical and histopathological markers were demonstrated in rats fed a high-fat diet.

RESULTS

Boswellia serrata extract inhibited alterations in pancreatic lipase activity, but orlistat was more efficacious. B. serrata and ephidrene, but not orlistat, significantly suppressed cumulative food intake in mice. In obese rats, B. serrata or orlistat significantly decreased weight gain and weight of visceral white adipose tissue. B. serrata-treated animals exhibited a significant reduction in serum glucose, TC, TG, LDL-C, FFA, IL-1β, TNF-α, insulin and leptin levels of obese rat groups while HDL-C and adiponectin levels were significantly increased by orlistat or B. serrata extract. Histopathological examination of the liver revealed that B. serrata was more effective than orlistat in alleviating steatosis and adipocyte hypertrophy shown in obese control rats.

CONCLUSIONS

Boswellia serrata is as effective as orlistat in preventing obesity, hyperlipidemia, steatosis and insulin resistance. These actions may be mediated by suppression of food intake and decrease levels of TNF-α, IL-1β and leptin resistance along with increasing adiponectin.

Fructose-rich diet differently affects angiotensin II receptor content in the nucleus and a plasma membrane fraction of visceral adipose tissue

The adipose tissue renin-angiotensin system (RAS) is proposed to be a pathophysiological link between adipose tissue dysregulation and metabolic disorders induced by a fructose-rich diet (FRD). RAS can act intracellularly. We hypothesized that adipocyte nuclear membranes possess angiotensin receptor types 1 and 2 (AT1R and AT2R), which couple to nuclear signaling pathways and regulate oxidative gene expression under FRD conditions. We analyzed the effect of consumption of 10% fructose solution for 9 weeks on biochemical parameters, adipocyte morphology, and expression of AT1R, AT2R, AT1R-associated protein (ATRAP), NADPH oxidase 4 (NOX4), matrix metalloproteinase-9 (MMP-9), and manganese superoxide dismutase (MnSOD) in adipose tissue of Wistar rats. We detected AT1R and AT2R in the nuclear fraction. FRD reduced the level of angiotensin receptors in the nucleus, while increased AT1R and decreased AT2R levels were observed in the plasma membrane. FRD increased the ATRAP mRNA level and decreased MnSOD mRNA and protein levels. No significant differences were observed for MMP-9 and NOX4 mRNA levels. These findings coincided with hyperleptinemia, elevated blood pressure and triglycerides, and unchanged visceral adipose tissue mass and morphology in FRD rats. Besides providing evidence for nuclear localization of angiotensin receptors in visceral adipose tissue, this study demonstrates the different effects of FRD on AT1R expression in different cellular compartments. Elevated blood pressure and decreased antioxidant capacity in visceral fat of fructose-fed rats were accompanied by an increased AT1R level in the plasma membrane, while upregulation of ATRAP and a decrease of nuclear membrane AT1R suggest an increased capacity for attenuation of excessive AT1R signaling and visceral adiposity.