Nannochloropsis oceanica as a Microalgal Food Intervention in Diet-Induced Metabolic Syndrome in Rats

The microalgal genus Nannochloropsis has broad applicability to produce biofuels, animal feed supplements and other value-added products including proteins, carotenoids and lipids. This study investigated a potential role of N. oceanica in the reversal of metabolic syndrome. Male Wistar rats (n = 48) were divided into four groups in a 16-week protocol. Two groups were fed either corn starch or high-carbohydrate, high-fat diets (C and H, respectively) for the full 16 weeks. The other two groups received C and H diets for eight weeks and then received 5% freeze-dried N. oceanica in these diets for the final eight weeks (CN and HN, respectively) of the protocol. The H diet was high in fructose and sucrose, together with increased saturated and trans fats. H rats developed obesity, hypertension, dyslipidaemia, fatty liver disease and left ventricular fibrosis. N. oceanica increased lean mass in CN and HN rats, possibly due to the increased protein intake, and decreased fat mass in HN rats. Intervention with N. oceanica did not change cardiovascular, liver and metabolic parameters or gut structure. The relative abundance of Oxyphotobacteria in the gut microbiota was increased. N. oceanica may be an effective functional food against metabolic syndrome as a sustainable protein source.

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Tropical Seaweeds Improve Cardiovascular and Metabolic Health of Diet-Induced Obese and Hypertensive Rats

Proceedings ◽

10.3390/iecn2020-07011 ◽

2020 ◽

Vol 61 (1) ◽

pp. 9

Author(s):

Ryan du Preez ◽

Sunil K. Panchal ◽

Lindsay Brown

Keyword(s):

Gut Microbiota ◽

Corn Starch ◽

Plasma Lipid ◽

Inflammatory Cells ◽

Left Ventricular ◽

Metabolic Health ◽

Liver Fat ◽

Collagen Deposition ◽

Male Wistar Rats ◽

Obesity Hypertension

Seaweeds have been an important part of the diet of coastal populations in Asia possibly for millennia but only a few scattered coastal communities in Europe and the Americas have maintained these traditions. Our studies have investigated the potential of two tropical seaweeds grown commercially in Asia, Sarconema and Caulerpa spp., as functional foods for the reversal of metabolic syndrome and possible mechanisms. Sarconema spp. are a source of carrageenans used as thickening and gelling agents in foods, while Caulerpa spp. are consumed in Southeast Asia as low-energy foods with high contents of vitamins and minerals. For our studies, male Wistar rats were divided into groups in a 16-week protocol: corn starch diet-fed rats (C); C rats supplemented with 5% dried seaweed for the last 8 weeks; high-carbohydrate, high-fat diet-fed rats (H); and H rats supplemented with 5% dried seaweed for the last 8 weeks. H rats developed obesity, hypertension, dyslipidaemia, glucose intolerance, fatty liver and increased left ventricular collagen deposition, infiltration of inflammatory cells and plasma liver enzyme activities. Seaweed supplementation decreased body weight, abdominal and liver fat, systolic blood pressure, plasma lipid concentrations, plasma activities of liver enzymes and collagen deposition. Furthermore, seaweed supplementation modulated gut microbiota. Possible mechanisms for improved cardiovascular and metabolic health include a reduced infiltration of inflammatory cells into organs as well as an increased intake of fibre modulating gut microbiota composition.

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Physiological and Metabolic Effects of Yellow Mangosteen (Garcinia dulcis) Rind in Rats with Diet-Induced Metabolic Syndrome

International Journal of Molecular Sciences ◽

10.3390/ijms21010272 ◽

2019 ◽

Vol 21 (1) ◽

pp. 272 ◽

Cited By ~ 6

Author(s):

Oliver D. John ◽

Peter Mouatt ◽

Marwan E. Majzoub ◽

Torsten Thomas ◽

Sunil K. Panchal ◽

...

Keyword(s):

Metabolic Syndrome ◽

High Fat Diet ◽

Corn Starch ◽

Left Ventricular ◽

Metabolic Effects ◽

High Fat ◽

High Carbohydrate ◽

Colonic Microbiota ◽

Freeze Dried ◽

Fruit Rind

Metabolic syndrome is a cluster of disorders that increase the risk of cardiovascular disease and diabetes. This study has investigated the responses to rind of yellow mangosteen (Garcinia dulcis), usually discarded as waste, in a rat model of human metabolic syndrome. The rind contains higher concentrations of phytochemicals (such as garcinol, morelloflavone and citric acid) than the pulp. Male Wistar rats aged 8–9 weeks were fed either corn starch diet or high-carbohydrate, high-fat diet for 16 weeks, which were supplemented with 5% freeze-dried G. dulcis fruit rind powder during the last 8 weeks. We characterised metabolic, cardiovascular, liver and gut microbiota parameters. High-carbohydrate, high-fat diet-fed rats developed abdominal obesity, hypertension, increased left ventricular diastolic stiffness, decreased glucose tolerance, fatty liver and reduced Bacteroidia with increased Clostridia in the colonic microbiota. G. dulcis fruit rind powder attenuated these changes, improved cardiovascular and liver structure and function, and attenuated changes in colonic microbiota. G. dulcis fruit rind powder may be effective in metabolic syndrome by appetite suppression, inhibition of inflammatory processes and increased fat metabolism, possibly related to changes in the colonic microbiota. Hence, we propose the use of G. dulcis fruit rind as a functional food to ameliorate symptoms of metabolic syndrome.

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Achacha (Garcinia humilis) Rind Improves Cardiovascular Function in Rats with Diet-Induced Metabolic Syndrome

Nutrients ◽

10.3390/nu10101425 ◽

2018 ◽

Vol 10 (10) ◽

pp. 1425 ◽

Cited By ~ 7

Author(s):

Oliver John ◽

Stephen Wanyonyi ◽

Peter Mouatt ◽

Sunil Panchal ◽

Lindsay Brown

Keyword(s):

Metabolic Syndrome ◽

Glucose Tolerance ◽

High Fat Diet ◽

Corn Starch ◽

Left Ventricular ◽

South American ◽

High Fat ◽

Alcoholic Fatty Liver ◽

High Carbohydrate ◽

Male Wistar Rats

Garcinia humilis is a fruit known as achachairú. It is native to South American countries such as Bolivia, Peru, and Brazil, but it is also cultivated as achacha in northern Australia. The aim of this study was to determine the phytochemicals in achacha rind and pulp and to investigate these components as potential treatments for the symptoms of metabolic syndrome. Both rind and pulp contain procyanidins and citric acid rather than hydroxycitric acid. Male Wistar rats (8–9 weeks old) were fed with either high-carbohydrate, high-fat, or corn starch diets for 16 weeks. Intervention groups were fed with either diet supplemented with 1.5% G. humilis rind powder or 2.0% G. humilis pulp for the last 8 weeks of the protocol. Rats fed a high-carbohydrate, high-fat diet exhibited hypertension, dyslipidemia, central obesity, impaired glucose tolerance, and non-alcoholic fatty liver disease. G. humilis rind decreased systolic blood pressure, diastolic stiffness, left ventricular inflammatory cell infiltration, and collagen deposition in high-carbohydrate, high-fat diet-fed rats. However, there was no change in glucose tolerance, body weight, or body composition. Therefore, G. humilis rind, usually a food by-product, but not the edible pulp, showed potential cardioprotection with minimal metabolic changes in a rat model of diet-induced metabolic syndrome.

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Brown Seaweed Sargassum siliquosum as an Intervention for Diet-Induced Obesity in Male Wistar Rats

Nutrients ◽

10.3390/nu13061754 ◽

2021 ◽

Vol 13 (6) ◽

pp. 1754

Author(s):

Ryan du Preez ◽

Marie Magnusson ◽

Marwan E. Majzoub ◽

Torsten Thomas ◽

Christina Praeger ◽

...

Keyword(s):

Gut Microbiota ◽

Wistar Rats ◽

Corn Starch ◽

Therapeutic Potential ◽

Brown Seaweed ◽

Left Ventricular ◽

Fat Deposition ◽

Liver Fat ◽

Male Wistar Rats ◽

Ventricular Fibrosis

The therapeutic potential of Sargassum siliquosum grown in Australian tropical waters was tested in a rat model of metabolic syndrome. Forty-eight male Wistar rats were divided into four groups of 12 rats and each group was fed a different diet for 16 weeks: corn starch diet (C); high-carbohydrate, high-fat diet (H) containing fructose, sucrose, saturated and trans fats; and C or H diets with 5% S. siliquosum mixed into the food from weeks 9 to 16 (CS and HS). Obesity, hypertension, dyslipidaemia, impaired glucose tolerance, fatty liver and left ventricular fibrosis developed in H rats. In HS rats, S. siliquosum decreased body weight (H, 547 ± 14; HS, 490 ± 16 g), fat mass (H, 248 ± 27; HS, 193 ± 19 g), abdominal fat deposition and liver fat vacuole size but did not reverse cardiovascular and liver effects. H rats showed marked changes in gut microbiota compared to C rats, while S. siliquosum supplementation increased gut microbiota belonging to the family Muribaculaceae. This selective increase in gut microbiota likely complements the prebiotic actions of the alginates. Thus, S. siliquosum may be a useful dietary additive to decrease abdominal and liver fat deposition.

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Caulerpa lentillifera (Sea Grapes) Improves Cardiovascular and Metabolic Health of Rats with Diet-Induced Metabolic Syndrome

Metabolites ◽

10.3390/metabo10120500 ◽

2020 ◽

Vol 10 (12) ◽

pp. 500

Author(s):

Ryan du Preez ◽

Marwan E. Majzoub ◽

Torsten Thomas ◽

Sunil K. Panchal ◽

Lindsay Brown

Keyword(s):

Metabolic Syndrome ◽

Gut Microbiota ◽

Corn Starch ◽

Plasma Concentrations ◽

Inflammatory Cells ◽

Left Ventricular ◽

High Fat ◽

High Carbohydrate ◽

Insoluble Fibre ◽

Caulerpa Lentillifera

Caulerpa lentillifera (sea grapes) is widely consumed in South-East Asia as a low-energy food with high contents of vitamins and minerals. This study investigated dried sea grapes containing 16.6% insoluble fibre commercially produced in Vietnam as an intervention. We hypothesised that insoluble fibre is the primary metabolite that will reverse diet-induced metabolic syndrome. Male Wistar rats (n = 48) were randomly allocated to four groups in a 16 week protocol. Two groups were fed either corn starch (C) or high-carbohydrate, high-fat (H) diets for the full 16 weeks. The other two groups received C and H diets for eight weeks and then received C. lentillifera added to these diets for the final eight weeks (CCL and HCL, respectively). High-carbohydrate, high-fat diet-fed rats developed obesity, hypertension, dyslipidaemia, fatty liver disease and increased left ventricular collagen deposition. C. lentillifera supplementation in HCL rats decreased body weight, systolic blood pressure, plasma concentrations of total cholesterol and non-esterified fatty acids, inflammatory cells in heart and liver, and visceral adiposity. The Firmicutes to Bacteroidetes ratio decreased in the gut microbiota of HCL rats. Therefore, C. lentillifera attenuated cardiovascular and metabolic symptoms of metabolic syndrome in rats, possibly by preventing infiltration of inflammatory cells together with modulating gut microbiota.

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Inulin oligofructose attenuates metabolic syndrome in high-carbohydrate, high-fat diet-fed rats

British Journal Of Nutrition ◽

10.1017/s0007114516003627 ◽

2016 ◽

Vol 116 (9) ◽

pp. 1502-1511 ◽

Cited By ~ 19

Author(s):

Senthil A. Kumar ◽

Leigh C. Ward ◽

Lindsay Brown

Keyword(s):

Metabolic Syndrome ◽

Corn Starch ◽

Body Weight Gain ◽

Fasting Blood Glucose ◽

Plasma Concentrations ◽

Left Ventricular ◽

High Fat ◽

Soluble Fibre ◽

High Carbohydrate ◽

The Metabolic Syndrome

AbstractPrebiotics alter bacterial content in the colon, and therefore could be useful for obesity management. We investigated the changes following addition of inulin oligofructose (IO) in the food of rats fed either a corn starch (C) diet or a high-carbohydrate, high-fat (H) diet as a model of diet-induced metabolic syndrome. IO did not affect food intake, but reduced body weight gain by 5·3 and 12·3 % in corn starch+inulin oligofructose (CIO) and high-carbohydrate, high-fat with inulin oligofructose (HIO) rats, respectively. IO reduced plasma concentrations of free fatty acids by 26·2 % and TAG by 75·8 % in HIO rats. IO increased faecal output by 93·2 %, faecal lipid excretion by 37·9 % and weight of caecum by 23·4 % and colon by 41·5 % in HIO rats. IO improved ileal morphology by reducing inflammation and improving the density of crypt cells in HIO rats. IO attenuated H diet-induced increases in abdominal fat pads (C 275 (sem 19), CIO 264 (sem 40), H 688 (sem 55), HIO 419 (sem 32) mg/mm tibial length), fasting blood glucose concentrations (C 4·5 (sem 0·1), CIO 4·2 (sem 0·1), H 5·2 (sem 0·1), HIO 4·3 (sem 0·1) mmol/l), systolic blood pressure (C 124 (sem 2), CIO 118 (sem 2), H 152 (sem 2), HIO 123 (sem 3) mmHg), left ventricular diastolic stiffness (C 22·9 (sem 0·6), CIO 22·9 (sem 0·5), H 27·8 (sem 0·5), HIO 22·6 (sem 1·2)) and plasma alanine transaminase (C 29·6 (sem 2·8), CIO 32·1 (sem 3·0), H 43·9 (sem 2·6), HIO 33·6 (sem 2·0) U/l). IO attenuated H-induced increases in inflammatory cell infiltration in the heart and liver, lipid droplets in the liver and plasma lipids as well as impaired glucose and insulin tolerance. These results suggest that increasing soluble fibre intake with IO improves signs of the metabolic syndrome by decreasing gastrointestinal carbohydrate and lipid uptake.

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Low-Dose Curcumin Nanoparticles Normalise Blood Pressure in Male Wistar Rats with Diet-Induced Metabolic Syndrome

Nutrients ◽

10.3390/nu11071542 ◽

2019 ◽

Vol 11 (7) ◽

pp. 1542 ◽

Cited By ~ 1

Author(s):

Ryan du Preez ◽

Jessica Pahl ◽

Meenakshi Arora ◽

M. N. V. Ravi Kumar ◽

Lindsay Brown ◽

...

Keyword(s):

Blood Pressure ◽

Metabolic Syndrome ◽

Systolic Blood Pressure ◽

Wistar Rats ◽

Low Dose ◽

Left Ventricular ◽

High Dose ◽

Curcumin Nanoparticles ◽

Diastolic Stiffness ◽

Male Wistar Rats

Nanoparticle formulations improve bioavailability and so may allow low-dose formulations of food-derived compounds such as curcumin to attenuate chronic systemic disease despite intrinsically low oral bioavailability. The current study induced metabolic syndrome in male Wistar rats aged eight–nine weeks using a high-carbohydrate, high-fat diet (H) with corn starch diet (C) as control. Using a reversal protocol, rats were given curcumin as either nanoparticles encapsulated in poly(lactic–co–glycolic acid) (5 mg/kg/day, HCNP) or as an unformulated low dose or high-dose suspension in water (low-dose, 5 mg/kg/day, HC5; high-dose, 100 mg/kg/day, HC100) or blank nanoparticles (HBNP) for the final eight weeks of the 16 week study. We analysed cardiovascular parameters including systolic blood pressure and left ventricular diastolic stiffness along with histopathology, liver parameters including plasma liver enzymes, histopathology and metabolic parameters, including glucose tolerance, blood lipid profile and body composition, and plasma curcumin concentrations. HC100 and HCNP but not HBNP normalised systolic blood pressure (C = 120 ± 4; H = 143 ± 5; HBNP = 141 ± 3; HC5 = 143 ± 4; HC100 = 126 ± 4; HCNP = 128 ± 4 mmHg), left ventricular diastolic stiffness and liver fat deposition. No other improvements were induced in HC100 or HCNP or other intervention groups (HC5 and HBNP). We conclude that 5 mg/kg/day curcumin nanoparticles in H rats showed similar improvements in cardiovascular function as 100 mg/kg/day unformulated curcumin correlating with similar plasma curcumin concentrations.

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Carrageenans from the Red Seaweed Sarconema filiforme Attenuate Symptoms of Diet-Induced Metabolic Syndrome in Rats

Marine Drugs ◽

10.3390/md18020097 ◽

2020 ◽

Vol 18 (2) ◽

pp. 97 ◽

Cited By ~ 7

Author(s):

Ryan du Preez ◽

Nicholas Paul ◽

Peter Mouatt ◽

Marwan E. Majzoub ◽

Torsten Thomas ◽

...

Keyword(s):

Metabolic Syndrome ◽

High Fat Diet ◽

Corn Starch ◽

Dry Weight ◽

Left Ventricular ◽

Liver Fat ◽

Red Seaweed ◽

High Fat ◽

High Carbohydrate ◽

Sarconema Filiforme

Carrageenans are thickening and gelling agents that may provide health benefits. Iota (ι)-carrageenan, a linear sulfated polysaccharide, is produced by the red seaweed, Sarconema filiforme. This study investigated the potential of this seaweed as a functional food for the reversal of metabolic syndrome and possible mechanisms. Male Wistar rats were divided into four groups in a 16-week protocol: corn starch diet-fed rats (C); C rats supplemented with 5% S. filiforme for the last 8 weeks (CSF); high-carbohydrate, high-fat diet-fed rats (H); and H rats supplemented with 5% S. filiforme for the last 8 weeks (HSF). S. filiforme was produced in tank-based aquaculture yielding 27 g dry weight/day/m2 of culture area. H rats developed obesity, hypertension, dyslipidaemia, glucose intolerance, fatty liver and increased left ventricular collagen deposition. S. filiforme supplementation decreased body weight, abdominal and liver fat, systolic blood pressure, plasma total cholesterol concentrations, and plasma activities of alanine transaminase and aspartate transaminase. S. filiforme supplementation modulated gut microbiota without changing the Firmicutes to Bacteroidetes ratio. S. filiforme improved symptoms of high-carbohydrate, high-fat diet-induced metabolic syndrome in rats. Possible mechanisms include a reduced infiltration of inflammatory cells into organs as well as prebiotic actions in the gastrointestinal tract.

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Modulation of Renal Function in a Metabolic Syndrome Rat Model by Antioxidants in Hibiscus sabdariffa L.

Molecules ◽

10.3390/molecules26072074 ◽

2021 ◽

Vol 26 (7) ◽

pp. 2074

Author(s):

Félix Leao Rodríguez-Fierros ◽

Verónica Guarner-Lans ◽

María Elena Soto ◽

Linaloe Manzano-Pech ◽

Eulises Díaz-Díaz ◽

...

Keyword(s):

Metabolic Syndrome ◽

Renal Function ◽

Rat Model ◽

Natural Antioxidants ◽

Antioxidant Systems ◽

Hibiscus Sabdariffa ◽

Glutathione S Transferase ◽

Total Antioxidant ◽

Male Wistar Rats ◽

Obesity Hypertension

Metabolic syndrome (MS) is the association of three or more pathologies among which obesity, hypertension, insulin resistance, dyslipidemia, and diabetes are included. It causes oxidative stress (OS) and renal dysfunction. Hibiscus sabdariffa L. (HSL) is a source of natural antioxidants that may control the renal damage caused by the MS. The objective of this work was to evaluate the effect of a 2% HSL infusion on renal function in a MS rat model induced by the administration of 30% sucrose in drinking water. 24 male Wistar rats were divided into 3 groups: Control rats, MS rats and MS + HSL rats. MS rats had increased body weight, systolic blood pressure, triglycerides, insulin, HOMA index, and leptin (p ≤ 0.04). Renal function was impaired by an increase in perfusion pressure in the isolated and perfused kidney, albuminuria (p ≤ 0.03), and by a decrease in clearance of creatinine (p ≤ 0.04). The activity of some antioxidant enzymes including the superoxide dismutase isoforms, peroxidases, glutathione peroxidase, glutathione-S-transferase was decreased (p ≤ 0.05). Lipoperoxidation and carbonylation were increased (p ≤ 0.001). The nitrates/nitrites ratio, total antioxidant capacity, glutathione levels and vitamin C were decreased (p ≤ 0.03). The treatment with 2% HSL reversed these alterations. The results suggest that the treatment with 2% HSL infusion protects renal function through its natural antioxidants which favor an improved renal vascular response. The infusion contributes to the increase in the glomerular filtration rate, by promoting an increase in the enzymatic and non-enzymatic antioxidant systems leading to a decrease in OS and reestablishing the normal renal function.

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Coffee Pulp, a By-Product of Coffee Production, Modulates Gut Microbiota and Improves Metabolic Syndrome in High-Carbohydrate, High-Fat Diet-Fed Rats

Pathogens ◽

10.3390/pathogens10111369 ◽

2021 ◽

Vol 10 (11) ◽

pp. 1369

Author(s):

Nikhil S. Bhandarkar ◽

Peter Mouatt ◽

Marwan E. Majzoub ◽

Torsten Thomas ◽

Lindsay Brown ◽

...

Keyword(s):

Metabolic Syndrome ◽

Gut Microbiota ◽

High Fat Diet ◽

Plasma Concentrations ◽

Left Ventricular ◽

Raw Material ◽

High Fat ◽

Coffee Pulp ◽

High Carbohydrate ◽

Freeze Dried

Waste from food production can be re-purposed as raw material for usable products to decrease industrial waste. Coffee pulp is 29% of the dry weight of coffee cherries and contains caffeine, chlorogenic acid, trigonelline, diterpenes and fibre. We investigated the attenuation of signs of metabolic syndrome induced by high-carbohydrate, high-fat diet in rats by dietary supplementation with 5% freeze-dried coffee pulp for the final 8 weeks of a 16-week protocol. Coffee pulp decreased body weight, feed efficiency and abdominal fat; normalised systolic blood pressure, left ventricular diastolic stiffness, and plasma concentrations of triglycerides and non-esterified fatty acids; and improved glucose tolerance in rats fed high-carbohydrate, high-fat diet. Further, the gut microbiota was modulated with high-carbohydrate, high-fat diet and coffee pulp supplementation and 14 physiological parameters were correlated with the changes in bacterial community structures. This study suggested that coffee pulp, as a waste from the coffee industry, is useful as a functional food for improving obesity-associated metabolic, cardiovascular and liver structure and function, and gut microbiota.

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