Thymus atlanticus (Ball) Roussine Aqueous Extract Exerts Lipid-lowering and Anti-atherosclerotic Effects in Hyperlipidemic Guinea Pigs

BACKGROUND

Thymus atlanticus (Ball) Roussine (T. atlanticus) is traditionally used in the Moroccan high Atlas Mountains to treat several disorders, including cardiovascular disease. In the present study, the lipid-lowering and anti-atherosclerotic activities of the traditionally used aqueous extract of T. atlanticus were evaluated on guinea pigs subjected to chronic hyperlipidemia.

METHODS

Animals were given a diet containing 2% cholesterol and 20% lard for 12 weeks. Moreover, thyme extract was given daily at 400 mg/kg. At the end of the experiment, lipid levels and paraoxonase arylesterase activity were measured, and aorta histology was studied.

RESULTS

Our findings revealed that there was an important elevation of blood lipids in the HFD group along with a significant decrease in paraoxonase arylesterase activity (-40.06%). Moreover, the consumption of fat altered the histology of aorta by thickening the intima media and forming atherosclerotic lesions and foam cells in these tissues. However, the administration of thyme extract attenuated HFD-caused alterations by decreasing blood lipids, elevating paraoxonase activity (+24.04%), and limiting the progression of atherosclerotic lesions.

CONCLUSION

We conclude that the supplementation with the aqueous extract of T. atlanticus could potentially protect against hyperlipidemia and consequently, the development of atherosclerosis.

The Modulatory Bioeffects of Pomegranate (Punica granatum L.) Polyphenols on Metabolic Disorders: Understanding Their Preventive Role against Metabolic Syndrome

Modern research achievements support the health-promoting effects of natural products and diets rich in polyphenols. Pomegranate (PG) (Punica granatum L.) contains a considerable number of bioactive compounds that exert a broad spectrum of beneficial biological activities, including antimicrobial, antidiabetic, antiobesity, and atheroprotective properties. In this context, the reviewed literature shows that PG intake might reduce insulin resistance, cytokine levels, redox gene expression, blood pressure elevation, vascular injuries, and lipoprotein oxidative modifications. The lipid parameter corrective capabilities of PG-ellagitannins have also been extensively reported to be significantly effective in reducing hyperlipidemia (TC, LDL-C, VLDL-C, and TAGs), while increasing plasma HDL-C concentrations and improving the TC/HDL-C and LDL-C/HDL-C ratios. The health benefits of pomegranate consumption seem to be acheived through the amelioration of adipose tissue endocrine function, fatty acid utilization, GLUT receptor expression, paraoxonase activity enhancement, and the modulation of PPAR and NF-κB. While the results from animal experiments are promising, human findings published in this field are inconsistent and are still limited in several aspects. The present review aims to discuss and provide a critical analysis of PG's bioeffects on the components of metabolic syndrome, type-2 diabetes, obesity, and dyslipidemia, as well as on certain cardiovascular-related diseases. Additionally, a brief overview of the pharmacokinetic properties, safety, and bioavailability of PG-ellagitannins is included.

Narrative Review: The Effect of Vitamin A Deficiency on Gut Microbiota and Their Link with Autism Spectrum Disorder

Autism spectrum disorder (ASD) is a group of neurodevelopmental disorders defined by a lack of social behaviors, repetitive behaviors and nonverbal interactions, such as limited eye contact, facial expression, and body gesturing. It is not a single condition, but rather a multi-factorial disorder caused by hereditary and non-genetic risk factors, as well as their interaction. According to several studies, the gut microbiota may have a role in the pathophysiology of autism spectrum disorder. Various studies have found differences in the composition of the gastrointestinal (GI) microbiota in children with ASD compared to unaffected siblings and/or healthy unrelated controls. The processes that relate the gut microbiota to brain dysfunctions (the gut-brain axis) in ASD are yet to be fully understood. However, the differences in the gastrointestinal composition might be due to vitamin A deficiency because vitamin A (VA) plays a role in the regulation of the intestinal microbiota. This narrative review discusses the impact of vitamin A deficiency on the gut microbiota composition and tries to understand how this may contribute for the development and severity of ASD.

Loquat (Eriobotrya japonica (Thunb) Lindl.): Evaluation of nutritional value, polyphenol composition, antidiabetic effect, and toxicity of leaf aqueous extract

ETHNOPHARMACOLOGICAL RELEVANCE

Loquat (Eriobotrya japonica (Thunb.) Lindl.) is an evergreen tree native to China, which is introduced in many Mediterranean countries. As in many ancient medical systems, loquat leaves have been used in Moroccan traditional medicine to treat diabetes and its complications.

AIM OF THE STUDY

This study aims to determine the nutritional and polyphenol composition and to evaluate the in vivo antidiabetic, and antihyperlipidemic properties and oral toxicity of a leaf aqueous extract (LLE) derived from loquat grown in Morocco.

MATERIALS AND METHODS

Energy value and fiber, fatty acids, minerals, vitamins, total carbohydrate, sugar, lipid, and protein contents were determined according to international methods committee guidelines. Polyphenol profiling was carried out using the HPLC-DAD method. Mice fed a high-fat and high-glucose (HFG) diet for 10 weeks were used as a model to assess the antidiabetic and antihyperlipidemic effects of a daily administration of LLE at three different doses (150, 200, 250 mg/kg body weight (BW)/day), in comparison with metformin (50 mg/kg BW/day) and pravastatin (20 mg/kg BW/day). The oral toxicity was determined following OECD 425 Guideline.

RESULTS

Loquat leaves were found to be rich in fiber, minerals (potassium, calcium, magnesium, iron, and sodium), and vitamins (B2, B6, and B12) and lower in energy, sugar, and fat. Ten different phenolic compounds were characterized. Naringenin, procyanidin C1, epicatechin, and rutin were the more abundant compounds in LLE. The administration of the LLE dose-dependently ameliorated hyperglycemia, insulin resistance, oxidative stress, and hyperlipidemia in HFG diet-fed mice. The median lethal dose of LLE was higher than 5000 mg/kg BW.

CONCLUSIONS

Loquat leaves are a potential source of micronutrients and polyphenols with beneficial effects on diabetes and its complications.

Pomegranate (Punica granatum L.) Attenuates Neuroinflammation Involved in Neurodegenerative Diseases

Food scientists have studied the many health benefits of polyphenols against pernicious human diseases. Evidence from scientific studies has shown that earlier healthy lifestyle changes, particularly in nutrition patterns, can reduce the burden of age-related diseases. In this context, a large number of plant-derived components belonging to the class of polyphenols have been reported to possess neuroprotective benefits. In this review, we examined studies on the effect of dietary polyphenols, notably from Punica granatum L., on neurodegenerative disease, including Alzheimer's disease, which is symptomatically characterized by impairment of cognitive functions. Clinical trials are in favor of the role of some polyphenols in maintaining neuronal homeostasis and attenuating clinical presentations of the disease. However, discrepancies in study design often bring inconsistent findings on the same component and display differences in their effectiveness due to interindividual variability, bioavailability in the body after administration, molecular structures, cross-blood-brain barrier, and signaling pathways such as nuclear factor kappa B (NF-κB). Based on preclinical and clinical trials, it appears that pomegranate may prove valuable in treating neurodegenerative disorders, including Alzheimer's disease (AD) and Parkinson's disease (PD). Therefore, due to the lack of information on human clinical trials, future in-depth studies, focusing on human beings, of several bioactive components of pomegranate's polyphenols and their synergic effects should be carried out to evaluate their curative treatment.

Effect of supplementation with polyphenol extract of Thymus atlanticus on paraoxonase-1 activity, insulin resistance, and lipid profile in high-fat diet-fed hamsters

Thymus atlanticus has been used by Moroccan people to treat a variety of health problems, particularly metabolic disorders. In this study, hamsters fed a high-fat diet daily received distilled water (a positive control) or a single dose of Thymus atlanticus polyphenols (Pp) for 63 days. The negative control was fed a normal diet and received distilled water. Results showed that the supplementation of HFD with Pp significantly (p < .001) reduced the levels of MDA and LDL cholesterol, restored insulin level, and increased the activities of serum paraoxonase-1 and HDL cholesterol levels, but did not affect (p > .05) the activity of superoxide dismutase and glutathione peroxidase when compared with the group feeding HFD alone. Thymus atlanticus could be an effective agent against dyslipidemia, oxidative stress, and insulin resistance. PRACTICAL APPLICATIONS: HFD consumption is a risk factor for oxidative stress and the development of metabolic disorders, such as hyperlipidemia and insulin resistance, which may result in atherosclerosis and related cardiovascular diseases, the leading causes of death globally. The management of these alterations is an important strategy to prevent and treat heart complications. Our results showed thatT. atlanticus effectively alleviated HFD-induced hyperlipidemia and insulin resistance and improved PON1 activity. T. atlanticus is a source of biomolecules that may be an effective supplement for controlling HFD-related metabolic disorders. Therefore, the findings of this study may be helpful in the preparation of effective supplements from T. atlanticus to control metabolic disorders and related complications.

Antioxidant Effect of Moroccan Pomegranate (Punica granatum L. Sefri Variety) Extracts Rich in Punicalagin against the Oxidative Stress Process

Natural antioxidants products are widely distributed in food and medicinal plants. These natural antioxidants, especially polyphenols, exhibit a wide range of biological activities including anti-cancer, anti-inflammatory, and anti-atherosclerosis activities. Pomegranate (Punica granatum L.) is a rich source of polyphenolic components. The purpose of this study was to characterize the phenolic composition and flavonoids and anthocyanin content of different parts (peel and aril) of the Sefri variety of pomegranate. Our results showed that Peel extract was richer in these compounds than that of the Arils, especially in Punicalagin (A and B). DPPH free radical scavenging, reducing power (FRAP), β-carotene bleaching, and hydrogen peroxide scavenging assays revealed a greater dose-dependent activity of pomegranate peel phenolic extract (PPPE) compared to pomegranate aril phenolic extract (PAPE). PPPE was also more potent than PAPE concerning its ability to inhibit conjugated diene formation and to reduce α-tocopherol disappearance induced by CuSO4-mediated LDL peroxidation. Interestingly, both extracts (PPPE and PAPE) significantly inhibited lipid peroxidation and the formation of reactive oxygen species (ROS) in stressed J82 human bladder cancer cells. These results reflect the protective effects that this Moroccan variety of pomegranate can provide against the development of metabolic disorder, cancer, atherosclerosis, and cardiovascular disease. Given these properties, further studies should be undertaken to investigate possible applications of Sefri pomegranate extracts in the fields of food preservation and health supplements.

Thymus atlanticus polyphenol-rich extract regulates cholesterol metabolism by inhibiting its biosynthesis without affecting its excretion in hamsters fed a high-fat diet

CONTEXT

Thymus atlanticus has been reported to have significant hypolipidaemic effect in animal models. However, the mechanism of this hypolipidaemic action still unknown.

OBJECTIVE

To determinate the possible mechanism(s) of hypolipidaemic action of a Thymus atlanticus polyphenol-rich extract (PRE).

MATERIALS AND METHODS

Plasma, faecal, and liver cholesterol, bile acid content in the faeces, and gene expression level of HMG-CoA reductase, CYP7A1, ABCG5 and ABCG8 were analysed after 9 weeks in hamsters feeding normal diet, high-fat diet (HFD) or HFD supplemented with 400 mg/kg body weight/day of PRE.

RESULTS

PRE significantly decreased total cholesterol content (p < .05) and HMG-CoA reductase expression (p < .05), but did not affect the faecal cholesterol, bile acid contents and CYP7A1 and ABCG5/G8 expression (p > .05).

CONCLUSION

We can conclude that the T. atlanticus extract is efficient in the alleviation of chronic hyperlipidaemia by acting as cholesterol biosynthesis inhibitor.

Effect of polyphenol, flavonoid, and saponin fractions from Thymus atlanticus on acute and chronic hyperlipidemia in mice

Background

Thymus atlanticus is an endemic plant of the Mediterranean region, which has been used in the Moroccan mountain area to treat several diseases. This study aimed to investigate the effect of polyphenol, flavonoid, and saponin fractions derived from this plant on acute and chronic hyperlipidemia in male albino mice.

Results

The results indicated that the injection of Triton WR-1339 (20 mg/100 g body weight (B.wt.)) and 6-week administration of a high-fat diet (which is an 81.8% standard diet supplemented with 2% cholesterol, 16% lard, and 0.2% cholic acid) significantly increased plasma total cholesterol, triglycerides and low-density lipoprotein cholesterol (LDL-C), but did not affect high-density lipoprotein cholesterol (HDL-C) levels in mice. Administration of a single dose (2 mg/kg B.wt.) of polyphenol, flavonoid, or saponin fractions significantly suppressed the effect of Triton injection on plasma total cholesterol, triglycerides, and LDL-C. In addition, the supplementation of the high-fat diet with polyphenol fraction (2 mg/kg B.wt./day) prevented the increase of total cholesterol, triglycerides, and LDL-C, and effectively increased HDL-C level when compared to mice feeding only the high-fat diet.

Conclusion

In conclusion, phenolic compounds from Thymus atlanticus possess a significant hypocholesterolemic and hypotriglyceridemic effects and, therefore, could have an important role in the management of dyslipidemia.

Anti-inflammatory and anticoagulant effects of polyphenol-rich extracts from Thymus atlanticus: An in vitro and in vivo study

ETHNOPHARMACOLOGICAL EVIDENCE

Thymus atlanticus (TA) is used in traditional medicine in Morocco to treat chronic inflammatory diseases, after local and oral treatment.

AIM OF STUDY

This study aimed to investigate the in vitro and in vivo anti-inflammatory and anticoagulant activities of an aqueous extract (AE) and polyphenol fraction (PF) derived from TA.

MATERIALS AND METHODS

The effect of AE and PF on monocyte chemoattractant protein-1 (MCP-1) production by naïve and LPS-stimulated peritoneal macrophages isolated from C57Bl/6 mice was assessed by ELISA assay. The effect of chronic administration of the extracts at three different doses by oral rout for 2 weeks on blood coagulation and inflammation induced by carrageenan in Wistar rats was evaluated. In addition, the in vitro anticoagulant effect was tested on blood plasma collected from healthy rats using the activated partial thromboplastin time (APTT), prothrombin time (PT) and thrombin time (TT) tests. The acute toxicity of AE was investigated. Phytochemical analysis was carried out by HPLC.

RESULTS

Analysis by HPLC indicated rosmarinic acid as the main phenolic acid in TA extracts. Compared to control macrophages, MCP-1 level was lower in medium supplemented with AE at 50 and 500 μg/mL and PF at 500 μg/mL, but higher in medium with PF at 50 μg/mL. Rosmarinic and chicoric acids, served as controls, significantly decreased MCP-1 production. Chronic oral administration of TA extracts prevented inflammation induced by carrageenan and induced a significant prolongation of blood coagulation time, in a dose dependant manner, in Wistar rats. The results of the in vitro assay showed that the coagulation time was significantly prolonged in plasma incubated with extracts in APTT, PT and TT tests. Lethal dose 50 of AE in mice was 27.90 ± 1.19 g/kg.

CONCLUSION

This study indicated TA as an herb with anti-inflammatory and anticoagulant proprieties and supports the traditional use of this plant for the treatment of inflammatory diseases.

Phenolic profile and anti-inflammatory activity of four Moroccan date (Phoenix dactylifera L.) seed varieties

Date (Phoenix dactylifera L.) seeds are seen as good drug to cure rheumatoid arthritis and asthma in Moroccan traditional medicine. The present research aimed to study the anti-inflammatory effect, of methanol extract of different date seed varieties using membrane stabilizing effect, nitric oxide radical scavenging activity, inhibition of protein denaturation, carrageenan-induced paw edema and croton oil induced ear edema. The polyphenolic profile was examined using HPLC-DAD. Rutin, quercetin, p-coumaric and caffeic acids were the main among the analysed phenolic compounds. Concerning the anti-inflammatory activity, the analysed date seed were significantly effective in scavenging nitric oxide free radical, in stabilisation of erythrocyte membrane and possessed a high anti denaturation effect. In agreement with this finding, date seed exhibited a profound ability to reduce paw and ear swelling induced by carrageenan and croton oil respectively. The biochemical parameters showed that date seed are able to reduce the erythrocyte sedimentation rate (ERS) and C-reactive protein (CRP) concentration in rats used in Carrageenan-induced paw edema model. The predominant phenolic compounds are the potential candidates that drive these activities and the differences observed among varieties are related to their chemical composition. These data suggest that date seeds can be explored as a therapeutic agent for the treatment of inflammatory diseases.

Antioxidant, anti-inflammatory and anticoagulant activities of three Thymus species grown in southeastern Morocco

Background

Thyme has been used for centuries in southeastern Morocco to treat a wide range of diseases such as inflammation disorders. The aim of the current study is to examine and to compare in vitro the anti-inflammatory, antioxidant, and anticoagulant activities of three thyme species grown in southeastern Morocco.

Results

Data showed that all studied species possess an important antioxidant activity: Thymus atlanticus (IC50 = 16.59 μg/mL), Thymus zygis (IC50 = 15.43 μg/mL), and Thymus satureioides (IC50 = 14.65 μg/mL). Concerning the anti-inflammatory activity, the highest effect was depicted in Thymus atlanticus followed by Thymus zygis and Thymus satureioides. With regard to the anticoagulant activity, the aqueous extract of these species prolongs activated partial thromboplastin time, prothrombin time, and thrombin time significantly (p < 0.05) in a dose-dependent manner.

Conclusion

Our results provide evidence that thymus extract exhibits marked antioxidant, anticoagulant, and anti-inflammatory effects, thus justifying the popular uses of these plants to treat some inflammatory and cardiovascular illnesses.