Effect of green tea extract on lipid profile in patients with type 2 diabetes mellitus: A systematic review and meta-analysis

BACKGROUND

Previous studies have indicated controversial results regarding the efficacy of green tea extract (GTE) in improving the lipid profile of type 2 diabetes mellitus (T2DM) patients. We aimed to conduct a systematic review and meta-analysis to pool data from randomized controlled trials (RCTs).

METHODS

A systematic search was performed in Web of Science, PubMed, and Scopus databases, without any language and time restriction until August 2019, to retrieve the RCTs which examined the effects of GTE on serum concentrations of high-density lipoprotein (HDL), low-density lipoprotein (LDL), triglyceride (TG) or total cholesterol (TC) in T2DM patients. Meta-analyses were carried out using a random effects model. I2 index was used to evaluate the heterogeneity.

RESULTS

Initial search yielded 780 publications. Of these, seven studies were eligible. The supplementary intake of GTE improved lipid profile by reducing serum TG concentrations in patients with T2DM. Meanwhile, subgroup analyses based on duration of interventions (≤8 and > 8 weeks) and intervention dosage (≤800 and > 800 mg/day) showed that the GTE supplementation longer than 8 weeks and in doses >800 mg/day resulted in a significant decrease in serum TG concentrations. Furthermore, intervention longer than 8 weeks with doses lower than 800 mg/day resulted in a significant reduction in serum TC concentrations.

CONCLUSION

In conclusion, present systematic review and meta-analysis revealed that the supplementary intake of GTE may improve lipid profile by reducing serum concentrations of TG in patients with T2DM. Furthermore, the results of our stratified analyses suggested that long-term GTE intervention may reduce serum concentrations of TG and TC.

The selective glucocorticoid receptor antagonist CORT125281 has tissue-specific activity

Glucocorticoids mediate numerous essential processes in the human body via binding to the glucocorticoid receptor (GR). Excessive GR signaling can cause disease, and GR antagonists can be used to treat many symptoms of glucocorticoid-induced pathology. The purpose of this study was to characterize the tissue-specific properties of the selective GR antagonist CORT125281. We evaluated the antagonistic effects of CORT125281 upon acute and subchronic corticosterone exposure in mice. In the acute corticosterone setting, hypothalamus-pituitary-adrenal-axis activity was investigated by measurement of basal- and stress-induced corticosterone levels, adrenocorticotropic hormone levels and pituitary proopiomelanocortin expression. GR signaling was evaluated by RT-PCR analysis of GR-responsive transcripts in liver, muscle, brown adipose tissue (BAT), white adipose tissue (WAT) and hippocampus. Pretreatment with a high dose of CORT125281 antagonized GR activity in a tissue-dependent manner. We observed complete inhibition of GR-induced target gene expression in the liver, partial blockade in muscle and BAT and no antagonism in WAT and hippocampus. Tissue distribution only partially explained the lack of effective antagonism. CORT125281 treatment did not disinhibit the hypothalamus-pituitary-adrenal neuroendocrine axis. In the subchronic corticosterone setting, CORT125281 partially prevented corticosterone-induced hyperinsulinemia, but not hyperlipidemia and immune suppression. In conclusion, CORT125281 antagonizes GR transcriptional activity in a tissue-dependent manner and improves corticosterone-induced hyperinsulinemia. Tailored dosing of CORT125281 may allow tissue-specific inhibition of GR transcriptional activity.

1H-NMR Metabolomics Analysis of the Effect of Rubusoside on Serum Metabolites of Golden Hamsters on a High-Fat Diet

Rubusoside is a natural sweetener and the active component of Rubus suavissimus. The preventive and therapeutic effect of rubusoside on high-fat diet-induced (HFD) serum metabolite changes in golden hamsters was analyzed by ¹H-NMR metabolomics to explore the underlying mechanism of lipid metabolism regulation. ¹H-NMR serum metabolomics analyses revealed a disturbed amino acid-, sugar-, fat-, and energy metabolism in HFD animals. Animals supplemented with rubusoside can partly reverse the metabolism disorders induced by high-fat diet and exerted good anti-hypertriglyceridemia effect by intervening in some major metabolic pathways, involving amino acid metabolism, synthesis of ketone bodies, as well as choline and 4-hydroxyphenylacetate metabolism. This study indicates that rubusoside can interfere with and normalize high-fat diet-induced metabolic changes in serum and could provide a theoretical basis to establish rubusoside as a potentially therapeutic tool able to revert or prevent lipid metabolism disorders.

Purslane and Garden Cress Seeds as Source of Unconventional Edible Oils for Prevention of Hyperlipidemia

BACKGROUND AND OBJECTIVE

Hyperlipidemia (HLP) is a leading cause for cardiovascular disease and atherosclerosis. Insufficient physical activity and unhealthy diet plays an important role in the progression of HLP. The present study was conducted to investigate the protective effect of 2 unconventional edible oils (purslane and garden cress) on hyperlipidemia.

MATERIALS AND METHODS

Diet high in fat and cholesterol was used as inducer of hyperlipidemia in rats for 5 weeks. Plasma and hepatic lipid profile were assessed. Plasma levels of malondialdehyde (MDA) as lipid peroxidation indicator was determined. Liver transaminases (AST and ALT) as liver function indicator and kidney function (creatinine and urea) were evaluated.

RESULTS

Results clarified significant elevation in plasma and liver lipid profiles, MDA, liver enzymes (AST and ALT) and kidney function (creatinine and urea) in hyperlipidemic control compared to normal control. Supplementation with purslane and garden cress seeds oils either in diet or oral showed significant improvement in all the studied parameters.

CONCLUSION

Purslane and garden cress oils investigated in the current study produced significant reduction and elevation in bad and good cholesterol, respectively in plasma. Also both oils reduced hepatic lipid accumulation effectively in hyperlipidemia model in rats. Oils administration reduced plasma malondialdehyde and improves liver and kidney functions.

Starch sources influence lipidaemia of diabetic dogs

BACKGROUND

Hyperlipidaemia is considered a cause of other diseases that are clinically important and potentially life threatening. Combination of pea and barley as exclusive starch sources is known to interfere with glycemic control in diabetic dogs, but their effect on lipid profile of hiperlipidaemic dogs is yet to be evaluated. Twelve adult diabetic dogs were fed three dry extruded diets with different starch sources and different fat levels: peas and barley (PB), maize (Mi), and peas, barley and rice (Ba) with 15.7, 15.6 and 9.0% of their dry matter as fat, respectively. Plasmatic cholesterol and triglycerides concentration curves over 10 h were obtained after 60 days on each diet and with the same NPH insulin dose. ANOVA test or Friedman test were used to compare the dietary effects on triglycerides and cholesterol variables among the diets.

RESULTS

Dogs presented lower mean (p = 0.05), fasting (p = 0.03), and time 8-h postprandial (p = 0.05) triglyceridemia after PB diet period than Ba diet period and time 4-h postprandial (p = 0.02) lower after PB than Mi diet. Cholesterolemia mean, minimum, maximum, area under the cholesterol curve and times points: 2, 4, 6, 8 and 10-h postprandial, had lower values after PB ingestion in comparison to Mi, without difference to Ba diet.

CONCLUSION

Inclusion of pea and barley, as exclusive starch sources, in therapeutic diets for diabetic dogs can minimize plasmatic triglycerides and cholesterol concentration at fasting and at different postprandial time, compared to the maize diet or diet with lesser fat content.

Hypolipidemic potential of sterol containing fractions of Jolyna laminarioides: a brown alga

Solvent fractions (n-hexane, cholorofrom, methanol) and fractions containing sterols of Jolyna laminarioides was evaluated in triton-induced and high-fat-diet induced hyperlipidemic rats. Oral administration of J. laminarioides significantly reduced the elevated level of serum total cholesterol, triglycerides and LDL-c, both in triton induced and high fat diet induced hyperlipidemic rat models with increased serum HDL-c. Chloroform: methanol fraction (2:1) and n-hexane fraction containing sterol showed promising results in reducing LDL-c. The methanol fraction showed hypolipidemic effect by increasing HDL-c (90%). The extracts and fractions of the seaweed also decreased the increased level of cardiac and hepatic marker enzymes beside lowering lipid profile. J. laminarioides exhibited high anti-hyperlipidemic effects both in triton induced and high fat diet induced hyperlipidemic rats.

mTORC1 restrains adipocyte lipolysis to prevent systemic hyperlipidemia

Objective

Pharmacological agents targeting the mTOR complexes are used clinically as immunosuppressants and anticancer agents and can extend the lifespan of model organisms. An undesirable side effect of these drugs is hyperlipidemia. Although multiple roles have been described for mTOR complex 1 (mTORC1) in lipid metabolism, the etiology of hyperlipidemia remains incompletely understood. The objective of this study was to determine the influence of adipocyte mTORC1 signaling in systemic lipid homeostasis in vivo.

Methods

We characterized systemic lipid metabolism in mice lacking the mTORC1 subunit Raptor (Raptor^aKO), the key lipolytic enzyme ATGL (ATGL^aKO), or both (ATGL-Raptor^aKO) in their adipocytes.

Results

Mice lacking mTORC1 activity in their adipocytes failed to completely suppress lipolysis in the fed state and displayed prominent hypertriglyceridemia and hypercholesterolemia. Blocking lipolysis in their adipose tissue restored normal levels of triglycerides and cholesterol in the fed state as well as the ability to clear triglycerides in an oral fat tolerance test.

Conclusions

Unsuppressed adipose lipolysis in the fed state interferes with triglyceride clearance and contributes to hyperlipidemia. Adipose tissue mTORC1 activity is necessary for appropriate suppression of lipolysis and for the maintenance of systemic lipid homeostasis.

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Inhibition of adipose mTORC1 causes hypertriglyceridemia prior to lipodystrophy.

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Genetically inhibiting lipolysis reverses the increase in plasma TG.

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Acute pharmacological inhibition of lipolysis reverses the increase in plasma TG caused by rapamycin treatment.

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Unrestrained lipolysis impairs LPL activity and decreases TG clearance.

Creosote bush-derived NDGA attenuates molecular and pathological changes in a novel mouse model of non-alcoholic steatohepatitis (NASH)

Creosote bush (Larrea tridentata)-derived nordihydroguaiaretic acid (NDGA) was shown to have profound effects on the core components of metabolic syndrome. This study investigated the in vivo potential of NDGA for prevention or attenuation of the pathophysiologic abnormalities of NASH. A novel dietary NASH model with feeding C57BL/6J mice with a high trans-fat, high cholesterol and high fructose (HTF) diet, was used. The HTF diet fed mice exhibited obesity, insulin resistance, hepatic steatosis, fibrosis, inflammation, ER stress, oxidative stress, and liver injury. NDGA attenuated these metabolic abnormalities as well as hepatic steatosis and fibrosis together with attenuated expression of genes encoding fibrosis, progenitor and macrophage markers with no effect on the levels of mRNAs for lipogenic enzymes. NDGA increased expression of fatty acid oxidation genes. In conclusion, NDGA exerts anti-NASH/anti-fibrotic actions and raises the therapeutic potential of NDGA for treatment of NASH patients with fibrosis and other associated complications.

Short-Term Betanin Intake Reduces Oxidative Stress in Wistar Rats

Oxidative stress is a common condition described in risk factors for cardiovascular disease. Betanin, a bioactive pigment from red beetroot demonstrates anti-inflammatory and antioxidant properties. The main aim of this study was to evaluate the short-term intake of betanin against oxidative stress in a rodent model, a common condition described in several risk factors for cardiovascular disease. Oxidative stress was induced in Wistar rats by a hyperlipidemic diet for 60 days, followed by betanin administration (20 mg·kg-1) through oral gavage for 20 days. Plasma biochemical parameters and antioxidant enzyme activities were evaluated. Lipid peroxidation and histopathological changes were determined in the liver. The hyperlipidemic diet caused hyperglycemia, hyperinsulinemia, insulin resistance, and increases in alanine transaminase and aspartate transaminase levels. Oxidative stress status was confirmed by reduction of antioxidant enzyme activities, increased lipid peroxidation, and liver damage. Purified betanin regulated glucose levels, insulin, and insulin resistance. Hepatic damage was reversed as evidenced by the reduction in alanine transaminase and aspartate transaminase levels and confirmed by histological analyses. Betanin reduced hepatic malondialdehyde and increased superoxide dismutase, catalase, and glutathione peroxidase activities. Short-term betanin intake modulated biochemical parameters, reversed hepatic tissue damage, and attenuated oxidative stress in Wistar rats.

Non-HDL cholesterol should not generally replace LDL cholesterol in the management of hyperlipidaemia

PURPOSE OF REVIEW

Non-HDL cholesterol was originally conceived as a therapeutic target for statin treatment in hypertriglyceridaemia when apolipoprotein B100 assays were not widely available. Recently non-HDL cholesterol has been recommended to replace LDL cholesterol in the clinical management of dyslipidaemia routinely in general medical practice. This is misguided.

RECENT FINDINGS

Non-HDL cholesterol is heterogeneous, constituting a mixture of triglyceride-rich VLDL, intermediate density lipoprotein and LDL in which small dense LDL is poorly represented and to which VLDL cholesterol contributes increasingly as triglyceride levels rise. This makes it unsuitable as a goal of lipid-lowering treatment or as an arbiter of who should receive such treatment. Results of trials designed to lower LDL cholesterol are not easily translated to non-HDL cholesterol. Fasting is no longer thought essential for screening the general population for raised LDL cholesterol. ApoB100 measurement also does not require fasting even in rarer more extreme lipoprotein disorders encountered in the Lipid Clinic, provides greater precision and specificity and overcomes the problems posed by LDL and non-HDL cholesterol. It is more easily interpreted both in diagnosis and as a therapeutic goal and it includes SD-LDL.

SUMMARY

If we are to discourage use of LDL cholesterol, it should be in favour of apoB100 not non-HDL cholesterol.

Indole-3-carbinol inhibits lipid deposition and promotes autophagy in hyperlipidemia zebrafish larvae

Indole-3-carbinol (I3C) is extracted from cruciferous vegetables and is well known for its anti-cancer, antioxidant and anti-inflammatory effects. This study investigated the protective effect of I3C in hyperlipidemia zebrafish larvae and early life stage toxicity of I3C on zebrafish embryos/larvae. Zebrafish larvae were fed with 4% high-cholesterol diet (HCD) and treated with I3C 2.5μmol/L and 5μmol/L for two weeks. Confocal image analysis, oil Red O staining were used to analysis vascular lipid accumulation and western blotting was used to evaluate possible mechanics. In addition, zebrafish embryos were treated with I3C for 96 h to assess the general toxicity and cardiotoxicity. We found that lipid deposition on vasculature was dose-dependently decreased in the I3C treated groups as compared with control group (47%, 23%, p<0.01). Moreover, we demonstrated that I3C inhibited lipid deposition by inducing autophagy, as identified by the enhancement of LC3-II, beclin-1, hVps34 and m-cathepsin D as well as by the reduction of P62, Bcl-2, Akt, p- Akt, mTOR, and p- mTOR in HCD fed zebrafish larvae (p<0.05). In summary, I3C shows protective effects on hyperlipidemia zebrafish larvae and maybe a promising multitarget drug in the prevention and protection against atherosclerotic.

Effect of Nutrient and Micronutrient Intake on Chylomicron Production and Postprandial Lipemia

Postprandial lipemia, which is one of the main characteristics of the atherogenic dyslipidemia with fasting plasma hypertriglyceridemia, low high-density lipoprotein cholesterol and an increase of small and dense low-density lipoproteins is now considered a causal risk factor for atherosclerotic cardiovascular disease and all-cause mortality. Postprandial lipemia, which is mainly related to the increase in chylomicron production, is frequently elevated in individuals at high cardiovascular risk such as obese or overweight patients, type 2 diabetic patients and subjects with a metabolic syndrome who share an insulin resistant state. It is now well known that chylomicron production and thus postprandial lipemia is highly regulated by many factors such as endogenous factors: circulating factors such as hormones or free fatty acids, genetic variants, circadian rhythms, or exogenous factors: food components, dietary supplements and prescription drugs. In this review, we focused on the effect of nutrients, micronutrients and phytochemicals but also on food structure on chylomicron production and postprandial lipemia.

Proanthocyanidins of Natural Origin: Molecular Mechanisms and Implications for Lipid Disorder and Aging-Associated Diseases

Proanthocyanidins are phytonutrients formed by oligomerization or polymerization of subunits catechin, epicatechin, and their gallic acid esters. Proanthocyanidins are a component of many plants and thus form an integral part of the human diet. Oligomeric proanthocyanidins are currently marketed as medicinal products that target vascular disorders and chronic pathological conditions, many of which are age-associated. Proanthocyanidins are also characterized by their effects on energy homeostasis. Not dissimilar to their chemically synthesized counterparts, naturally extracted proanthocyanidins act via inhibition of lipases, stimulation of energy expenditure, or suppression of appetite. Here we review the current knowledge-base and highlight challenges and future impacts regarding involvement of proanthocyanidins in global lipid metabolism, with a focus on the molecular mechanisms and pathological conditions that progress with aging.

Knowing is not half the battle: Impacts of information from the National Health Screening Program in Korea

Health screening provides information on disease risk and diagnosis, but whether this promotes health is unclear. We estimate the impacts of information provided by Korea's National Health Screening Program by applying a regression discontinuity design around different biomarker thresholds of diabetes, obesity, and hyperlipidemia risk using administrative data that includes medical claims, biomarkers, and behavioral surveys over four years after screening. Generally, we find limited responses to disease risk information alone. However, we find evidence for weight loss around the high risk threshold for diabetes, where information is combined with active prompting for a secondary examination for diagnosis and treatment.

Prevention of Obesity and Hyperlipidemia by Heptamethoxyflavone in High-fat Diet-induced Rats

Polymethoxyflavones (PMFs) have been shown to prevent obesity, ameliorate type 2 diabetes, and regulate lipid metabolism in vitro and in vivo. However, little is known about the contribution of 3,5,6,7,8,3',4'-heptamethoxyflavone (HMF) to prevent obesity and regulate lipid metabolism in vivo. We aimed to investigate the potential efficacy of HMF on preventing obesity and hyperlipidemia in rats fed a high-fat diet (HFD) and its underlying mechanisms. Male Sprague-Dawley rats were fed a normal diet or an HFD with or without HMF (0.02%, 0.04% and 0.08%, w/w) for 6 weeks. The supplementation of HMF not only significantly decreased body weight gain (HFD, 336.50 ± 18.84 g; LHMF, 309.43 ± 20.74 g; MHMF, 296.83 ± 13.88 g; HHMF, 265.71 ± 19.09 g; respectively, p < 0.05) and adipose tissues weight ( p < 0.05), but also markedly lowered serum levels of total cholesterol, triacylglycerol, and low-density lipoprotein cholesterol ( p < 0.05) in the sixth week in a dose-dependent manner compared with the HFD group. HMF also significantly alleviated hepatic steatosis in the liver (liver weight g/100 g body weight of HFD, 4.86 ± 0.11%; LHMF, 4.02 ± 0.33%; MHMF, 4.05 ± 0.31%; HHMF, 3.72 ± 0.34%; respectively, p < 0.05). Furthermore, transcriptome analysis and real-time quantitative RT-PCR demonstrated that HMF supplementation markedly downregulated hepatic genes related to adipogenesis transcription and inflammatory responses, and significantly upregulated genes related to fatty acid oxidation and energy expenditure. These results indicated that HMF could effectively prevent obesity and hyperlipidemia by regulation of the expression of lipid metabolism-related and inflammatory response-related genes.

Heparin-binding EGF-like growth factor (HB-EGF) antisense oligonucleotide protected against hyperlipidemia-associated atherosclerosis

BACKGROUND AND AIMS

Heparin-binding EGF-like growth factor (HB-EGF) is a representative EGF family member that interacts with EGFR under diverse stress environment. Previously, we reported that the HB-EGF-targeting using antisense oligonucleotide (ASO) effectively suppressed an aortic aneurysm in the vessel wall and circulatory lipid levels. In this study, we further examined the effects of the HB-EGF ASO administration on the development of hyperlipidemia-associated atherosclerosis using an atherogenic mouse model.

METHODS AND RESULTS

The male and female LDLR deficient mice under Western diet containing 21% fat and 0.2% cholesterol content were cotreated with control and HB-EGF ASOs for 12 weeks. We observed that the HB-EGF ASO administration effectively downregulated circulatory VLDL- and LDL-associated lipid levels in circulation; concordantly, the HB-EGF targeting effectively suppressed the development of atherosclerosis in the aorta. An EGFR blocker BIBX1382 administration suppressed the hepatic TG secretion rate, suggesting a positive role of the HB-EGF signaling for the hepatic VLDL production. We newly observed that there was a significant improvement of the insulin sensitivity by the HB-EGF ASO administration in a mouse model under the Western diet as demonstrated by the improvement of the glucose and insulin tolerances.

CONCLUSION

The HB-EGF ASO administration effectively downregulated circulatory lipid levels by suppressing hepatic VLDL production rate, which leads to effective protection against atherosclerosis in the vascular wall.

Olanzapine Induced Dysmetabolic Changes Involving Tissue Chromium Mobilization in Female Rats

Atypical antipsychotics, such as olanzapine, are commonly prescribed to patients with schizophrenic symptoms and other psychiatric disorders. However, weight gain and metabolic disturbance cause adverse effects, impair patient compliance and limit clinical utility. Thus, a better understanding of treatment-acquired adverse effects and identification of targets for therapeutic intervention are believed to offer more clinical benefits for patients with schizophrenia. Beyond its nutritional effects, studies have indicated that supplementation of chromium brings about beneficial outcomes against numerous metabolic disorders. In this study, we investigated whether olanzapine-induced weight gain and metabolic disturbance involved chromium dynamic mobilization in a female Sprague-Dawley rat model, and whether a dietary supplement of chromium improved olanzapine-acquired adverse effects. Olanzapine medicated rats experienced weight gain and adiposity, as well as the development of hyperglycemia, hyperinsulinemia, insulin resistance, hyperlipidemia, and inflammation. The olanzapine-induced metabolic disturbance was accompanied by a decrease in hepatic Akt and AMP-activated Protein Kinase (AMPK) actions, as well as an increase in serum interleukin-6 (IL-6), along with tissue chromium depletion. A daily intake of chromium supplements increased tissue chromium levels and thermogenic uncoupling protein-1 (UCP-1) expression in white adipose tissues, as well as improved both post-olanzapine weight gain and metabolic disturbance. Our findings suggest that olanzapine medicated rats showed a disturbance of tissue chromium homeostasis by inducing tissue depletion and urinary excretion. This loss may be an alternative mechanism responsible for olanzapine-induced weight gain and metabolic disturbance.

Hypolipidemic and antioxidant activities of volatile oils from fresh leaves of Michelia martini Levl

.This study aimed to investigate the hypolipidemic and antioxidant activities of volatile oils from Michelia martini Levl. The antioxidant property of volatile oils from Michelia martini in vitro was investigated by establishment of various systems. High fat diet induced rats were used to assess the hypolipidemic and antioxidant activities of Michelia martini volatile oils in vivo. The level of total cholesterol, triglycerides, high density lipoprotein cholesterol, low density lipoprotein cholesterol, alanine transaminase, aspartate aminotransferase, alkaline phosphatase and gamma-glutamyl transpeptidase in serum, and the activities of catalase, malondialdehyde, super oxide dismutase and glutathione in liver of rats were assayed by standard procedures. Our results showed that Michelia martini exhibits strong hypolipidemic and antioxidant activities both in vitro and vivo. Our data were also supplemented with histopathological studies on liver tissues and aorta sections of rats.

Action of corilagin on hyperglycemia, hyperlipidemia and oxidative stress in streptozotocin-induced diabetic rats

Diabetes mellitus is the world's most common endocrine disease involving metabolic disorders of carbohydrate, protein and fat. This study was undertaken to investigate the anti-diabetic activity of corilagin, a member of polyphenolic tannins used against hyperglycemia and many other diseases in well-known animal models. Diabetes was induced chemically by intraperitoneal administration of Streptozotocin (40 mg/kg bw) to albino Wistar rats. Diabetic rats showed significant increase in the levels of fasting blood glucose, glycated haemoglobin, total cholesterol, triglyceride, low density lipoprotein cholesterol, very low density lipoprotein cholesterol, and a significant decrease in the level of body weight, plasma insulin, high density lipoprotein cholesterol, antioxidant activities, viz. superoxide dismutase, catalase and reduced glutathione when compared to controls. However, after 30 days of oral administration of corilagin (10 and 20 mg/kg bw/day) to these diabetic rats evoked significant alterations in the above mentioned parameters. The effect of corilagin was compared with the standard drug, glibenclamide (0.1 mg/kg body weight/day). Thus, the present study suggests that the corilagin acts as a natural, effective therapeutic agent to regulate diabetes, by exhibiting antidiabetic, antihyperlipidemic and antioxidant properties in STZ induced diabetic rats.

Ginger alleviates hyperglycemia-induced oxidative stress, inflammation and apoptosis and protects rats against diabetic nephropathy

Oxidative stress plays a major role in the development and progression of diabetic nephropathy (DN). In this study, the potential protective effect of ginger (Zingiber officinale) rhizome extract on hyperglycemia-induced oxidative stress, inflammation and apoptosis was investigated. An experimental diabetic rat model was induced by intraperitoneal injection of streptozotocin. Diabetic rats were treated orally with 400 or 800 mg/kg/day Z. officinale extract for six weeks. Diabetic animals exhibited elevated blood glucose levels and glycated hemoglobin (HbA1c) with altered lipid profile. Blood urea nitrogen, serum creatinine and urea, and urine albumin levels were significantly increased in diabetic rats. Treatment with Z. officinale ameliorated hyperglycemia, hyperlipidemia and kidney function. In addition, Z. officinale minimized the histological alterations in the kidney of diabetic rats. Chronic hyperglycemia resulted in a significant increase in malondialdehyde, protein carbonyl, pro-inflammatory cytokines, cytochrome c and caspase-3 in the kidney of rats. Z. officinale extract significantly attenuated oxidative stress, inflammation and apoptosis, and enhanced antioxidant defenses in the diabetic kidney. In conclusion, this study strongly suggests that Z. officinale rhizome extract exerts a protective role against diabetes-induced renal injury by ameliorating oxidative stress, inflammation and apoptosis.

Cost-effectiveness of Financial Incentives for Patients and Physicians to Manage Low-Density Lipoprotein Cholesterol Levels

IMPORTANCE

Financial incentives shared between physicians and patients were shown to significantly reduce low-density lipoprotein cholesterol (LDL-C) levels in a randomized clinical trial, but it is not known whether these health benefits are worth the added incentive and utilization costs required to achieve them.

OBJECTIVE

To evaluate the long-term cost-effectiveness of financial incentives on LDL-C level control.

DESIGN, SETTING, AND PARTICIPANTS

In this economic evaluation, a previously validated microsimulation computer model was parameterized using individual-level data from the randomized clinical trial on financial incentives, National Health and Nutrition Examination Surveys for model population inputs, and other published sources. The study was conducted from April 15, 2016, to March 29, 2018.

INTERVENTIONS

The following interventions were used: (1) usual care, (2) trial control strategy (increased cholesterol level monitoring and use of electronic pill bottles), (3) financial incentives for physicians, (4) financial incentives for patients, and (5) incentives shared between physicians and patients.

MAIN OUTCOMES AND MEASURES

Discounted costs (2017 US dollars), lifetime cardiovascular disease risk, quality-adjusted life-years (QALYs), and incremental cost-effectiveness ratios (ICERs).

RESULTS

The model population (n = 1 000 000 [30.7% women]) had similar mean (SD) age (61.5 [11.9] years) and LDL-C level (153.9 mg/dL) as the observed trial population (n = 1503 [42.7% women]; age, 62.0 [8.7] years; and LDL-C level, 160.6 mg/dL). Using base-case assumptions (including a 10-year waning period of LDL-C level reductions), the usual-care strategy was dominated (higher costs and lower QALYs) by all other strategies. Strategies for physician- or patient-only incentives were dominated by the shared-incentives strategy, which had an ICER of $60 000/QALY compared with the trial control strategy. In a sensitivity analysis regarding the duration of LDL-C level reductions, the shared-incentives strategy remained cost-effective (ICERs <$100 000/QALY and <$150 000/QALY) for scenarios with LDL-C level reductions lasting, with linear waning, at least 7 and 5 years, respectively. In the 1-way sensitivity analysis for the time horizon of the analysis, the ICER of the shared-incentives strategy exceeded $100 000/QALY at 11 years and $150 000/QALY at 8 years. In probabilistic sensitivity analysis, the shared-incentives intervention was cost-effective in 69% to 77% of iterations using cost-effectiveness thresholds of $100 000 to $150 000/QALY. Cost-effectiveness results were also sensitive to the duration of intervention costs.

CONCLUSIONS AND RELEVANCE

This study suggests that the financial incentives shared between patients and physicians for LDL-C level control meet conventional standards of cost-effectiveness, but these results appeared to be sensitive to assumptions about the durations of LDL-C level reductions and years of intervention costs included, as well as to the choice of time horizon.

Oral administration of Pantoea agglomerans-derived lipopolysaccharide prevents development of atherosclerosis in high-fat diet-fed apoE-deficient mice via ameliorating hyperlipidemia, pro-inflammatory mediators and oxidative responses

Pantoea agglomerans (P. agglomerans) is a Gram-negative bacterium that grows symbiotically with various edible plants, and the oral or sublingual administration of lipopolysaccharide derived from P. agglomerans (LPSp) have been suggested to contribute to prevention of immune-related diseases. Our previous study indicated that orally administered LPSp was shown to exhibit an LDL-lowering effect in hyperlipidemic volunteers; however, a preventive effect of LPSp on atherosclerosis is unclear. The present study attempted to evaluate the anti-atherosclerotic effect by LPSp in a mouse model of high-fat diet (HFD)-induced atherosclerosis. For 16 weeks, apoE-deficient mice were fed an HFD and received drinking water containing LPSp (0.3 or 1 mg/kg body weight/day). The results showed that the orally administered LPSp decreased body weight. A significant reduction in atherosclerotic plaque deposition was observed even with the lower dose of LPSp. The biochemical analyses showed that LPSp markedly improved glucose tolerance and reduced plasma LDL and oxidized LDL levels. In addition, LPSp significantly reduced the production of pro-inflammatory mediators including MCP-1 (in the plasma), TNF-α and IL-6 (in the colon), and decreased the oxidative burst activities in the peripheral blood sample. Taken together, these results suggest the possibility that oral administration of LPSp can effectively ameliorate HFD-induced hyperlipidemia and inflammatory/oxidative responses to prevent atherosclerosis and related metabolic disorders.

Health Benefits of the Mediterranean Diet: Metabolic and Molecular Mechanisms

Consuming a Mediterranean diet rich in minimally processed plant foods has been associated with a reduced risk of developing multiple chronic diseases and increased life expectancy. Data from several randomized clinic trials have demonstrated a beneficial effect in the primary and secondary prevention of cardiovascular disease, type 2 diabetes, atrial fibrillation, and breast cancer. The exact mechanism by which an increased adherence to the traditional Mediterranean diet exerts its favorable effects is not known. However, accumulating evidence indicates that the five most important adaptations induced by the Mediterranean dietary pattern are: (a) lipid-lowering effect, (b) protection against oxidative stress, inflammation and platelet aggregation, (c) modification of hormones and growth factors involved in the pathogenesis of cancer, (d) inhibition of nutrient sensing pathways by specific amino acid restriction, and (e) gut microbiota-mediated production of metabolites influencing metabolic health. More studies are needed to understand how single modifications of nutrients typical of the Mediterranean diet interact with energy intake, energy expenditure, and the microbiome in modulating the key mechanisms that promote cellular, tissue, and organ health during aging.

Effect of liraglutide on dietary lipid-induced insulin resistance in humans

AIMS

To test whether liraglutide suppresses postprandial elevations in lipids and thus protects against high saturated fatty acid (SFA) diet-induced insulin resistance.

METHODS

In a randomized placebo-controlled crossover study, 32 participants with normal or mildly impaired glucose tolerance received liraglutide and placebo for 3 weeks each. Insulin suppression tests (IST) were conducted at baseline and after a 24-hour SFA-enriched diet after each treatment. Plasma glucose, insulin, triglycerides and non-esterified fatty acids (NEFA) were measured over the initial 8 hours (breakfast and lunch) on the SFA diet. A subset of participants underwent ex vivo measurements of insulin-mediated vasodilation of adipose tissue arterioles and glucose metabolism regulatory proteins in skeletal muscle.

RESULTS

Liraglutide reduced plasma glucose, triglycerides and NEFA concentrations during the SFA diet (by 50%, 25% and 9%, respectively), and the SFA diet increased plasma glucose during the IST (by 36%; all P < .01 vs placebo). The SFA diet-induced impairment of vasodilation on placebo (-9.4% vs baseline; P < .01) was ameliorated by liraglutide (-4.8%; P = .1 vs baseline). In skeletal muscle, liraglutide abolished the SFA-induced increase in thioredoxin-interacting protein (TxNIP) expression (75% decrease; P < .01 vs placebo) and increased 5'AMP-activated protein kinase (AMPK) phosphorylation (50% vs -3%; P = .04 vs placebo).

CONCLUSIONS

Liraglutide blunted the SFA-enriched diet-induced peripheral insulin resistance. This effect may be related to improved microvascular function and modulation of TxNIP and AMPK pathways in skeletal muscle.