Intestinal Carbohydrate Absorption Research Articles

Protective Effects of Melatonin in High-Fat Diet-Induced Hepatic Steatosis via Decreased Intestinal Lipid Absorption and Hepatic Cholesterol Synthesis.

The preventative effect of melatonin on the development of obesity and the progression of fatty liver under a high-fat diet (HFD) has been well elucidated through previous studies. We investigated the mechanism behind this effect regarding cholesterol biosynthesis and regulation of cholesterol levels. Mice were divided into three groups: normal chow diet (NCD); HFD; and HFD and melatonin administration group (HFD+M). We assessed the serum lipid profile, mRNA expression levels of proteins involved in cholesterol synthesis and reabsorption in the liver and nutrient transporters in the intestines, and cytokine levels. Additionally, an in vitro experiment using HepG2 cells was performed. Expression of hepatic sterol regulatory element-binding protein 2 (SREBP-2), 3-hydroxy-3-methylglutaryl coenzyme A reductase (HMGCR), and low-density lipoprotein receptor (LDLR) demonstrated that melatonin administration significantly reduces hepatic cholesterol synthesis in mice fed an HFD. Expression of intestinal sodium-glucose transporter 1 (SGLT1), glucose transporter 2 (GLUT2), GLUT5, and Niemann-pick C1-like 1 (NPC1L1) demonstrated that melatonin administration significantly reduces intestinal carbohydrate and lipid absorption in mice fed an HFD. There were no differences in local and circulatory inflammatory cytokine levels among the NCD, HFD, and HFD+M group. HepG2 cells stimulated with palmitate showed reduced levels of SREBP, LDLR, and HMGCR indicating these results are due to the direct mechanistic effect of melatonin on hepatocytes. Collectively, these data indicate the mechanism behind the protective effects of melatonin from weight gain and liver steatosis under HFD is through a reduction in intestinal caloric absorption and hepatic cholesterol synthesis highlighting its potential in the treatment of obesity and fatty liver disease.

α- Glucosidase Inhibitory and Antioxidant Activities of Moluccella aucheri (Boiss.) Scheen Extracts

Background & Objective: α-Glucosidase is one of the main enzymes in the intestinal absorption of carbohydrates. Inhibition of this enzyme can improve postprandial hyperglycemia in diabetic patients. Also, antioxidants can ameliorate diabetes complications resulted from oxidative stress. In this study α-glucosidase inhibition, antioxidant activity and total phenol content of different extracts and obtained fractions of Moluccella aucheri have been evaluated.
 Materials & Methods: The ethanol extract of aerial parts of M. aucheri was fractionated using liquid extraction method with petroleum ether, dichloromethane and ethyl acetate, respectively. The extracts and the resulting fractions of M. aucheri were tested against α-glucosidase enzyme from yeast using an in vitro colorimetric model at λ 405 nm. Antioxidant activity was assessed using two different methods, ferric reducing antioxidant power (FRAP) and the scavenging activity of DPPH radicals’ methods.
 Results: The screening results indicated that the antioxidant activity and total phenolic content of the methanol extract were potentially higher than ethanol extract, while the ethanol extract inhibited α-glucosidase enzyme to a greater extent. Ethyl acetate fraction illustrated potentially the highest antioxidant activity and phenolic content, but its inhibition activity against α-glucosidase was placed after the petroleum ether fraction. Two previously isolated methoxy flavones; genkwanin, 5-hydroxyl-7, 4'-dimethoxyflavone inhibited the α-glucosidase enzyme strongly.
 Conclusion: Since the ethyl acetate extract has both considerable antioxidant activity and α-glucosidase inhibitory activity, it may be considered as a potential crude drug for diabetes.

An in-vivo study on postprandial hyperglycemia to assess antidiabetic activity of alcoholic extract of Cinnamomum verum bark

Background and objective Cinnamomum verum bark is locally known as ‘Daruchini’ and is traditionally reputed as an Ayurvedic medicine, which is used in the treatment of flatulence, toothache, heart diseases, fever, cough, cold, headache, and many others. In this study, we intended to explore the effectiveness of its activity on hyperglycemia.Materials and methods To evaluate its antihyperglycemic activity, we used various experimental designs, including the effect of plant extract on gastrointestinal (GI) motility in the Swiss albino mice model and intestinal disaccharidase enzyme activity and carbohydrate digestion and absorption in the gut of the Long Evans rats.Results and discussion The plant extract significantly (P<0.001) increased the GI motility rate by ∼16% than the control (distilled water, 10 ml/kg body weight) and indicated that it interfered with the rate of glucose absorption in the gut. Furthermore, treatment with C. verum caused a significant (P<0.05) dose-dependent reduction of intestinal disaccharidase enzyme activity from 1.63 to 1.21 µmol/mg protein/h in fasting Long Evans rats. Besides, the extract produced a similar effect in the acute oral sucrose (2.5 g/kg body weight) load assay, in which a substantial amount of unabsorbed sucrose was found in six different parts of the GI tract after sucrose administration. This indicates that C. verum can liberate GI content and reduce or delay glucose absorption.Conclusion All the findings of the present study point to the conclusion that C. verum has the potential to exert postprandial antihyperglycemic activity within type 2 diabetic animal models through reducing or delaying carbohydrate digestion and absorption in the gut.

Acute Low-Intensity Treadmill Running Upregulates the Expression of Intestinal Glucose Transporters via GLP-2 in Mice.

The effects of exercise on nutrient digestion and absorption in the intestinal tract are not well understood. A few studies have reported that exercise training increases the expression of molecules involved in carbohydrate digestion and absorption. Exercise was also shown to increase the blood concentration of glucagon-like peptide-2 (GLP-2), which regulates carbohydrate digestion and absorption in the small intestine. Therefore, we investigated the effects of exercise on the expression of molecules involved in intestinal digestion and absorption, including GLP-2. Six-week-old male mice were divided into a sedentary (SED) and low-intensity exercise (LEx) group. LEx mice were required to run on a treadmill (12.5 m/min, 1 h), whereas SED mice rested. All mice were euthanized 1 h after exercise or rest, and plasma, jejunum, ileum, and colon samples were collected, followed by analysis via IHC, EIA, and immunoblotting. The levels of plasma GLP-2 and the jejunum expression of the GLP-2 receptor, sucrase-isomaltase (SI), and glucose transporter 2 (GLUT2) were higher in LEx mice. Thus, we showed that acute low-intensity exercise affects the expression of molecules involved in intestinal carbohydrate digestion and absorption via GLP-2. Our results suggest that exercise might be beneficial for small intestine function in individuals with intestinal frailty.

Comparison of the Bifidogenic Effects of Goat and Cow Milk-Based Infant Formulas to Human Breast Milk in an in vitro Gut Model for 3-Month-Old Infants.

Human milk contains prebiotic components, such as human milk oligosaccharides (HMOs), which stimulate the growth of specific members of the infant gut microbiota (e.g., Bifidobacteria). Plant-based or synthetic oligosaccharides are often added to infant formulas to simulate the bifidogenic effect of HMOs. Cow milk, the most common source of protein in infant formula, and goat milk, used increasingly in the manufacture of infant formula, contain naturally-occurring prebiotics. This study compared the upper gastrointestinal digestion and subsequent colonic fermentation of human milk vs. goat and cow milk-based infant formulas (goat IF and cow IF, respectively), without additional oligosaccharides using an in vitro model for 3-month-old infants based on the Simulator of the Human Intestinal Microbial Ecosystem (SHIME®). First, a dialysis approach using 3.5 kDa membranes was demonstrated to simulate small intestinal absorption of carbohydrates in conditions similar to those in vivo. During the in vitro digestion experiment, oligosaccharides were detected in human milk and goat IF but barely detected in the cow IF. Further, all three milk matrices decreased colonic pH by boosting acetate, lactate, and propionate production, which related to increased abundances of acetate/lactate-producing Bifidobacteriaceae for human milk (+25.7%) and especially goat IF (33.8%) and cow IF (37.7%). Only cow IF stimulated butyrate production which correlated with an increase in Lachnospiraceae and Clostridiaceae. Finally, Enterobacteriaceae and Acidaminococcaceae also increased with all three milk matrices, while production of proteolytic metabolites (branched-chain fatty acids) was only detected for the cow IF. Overall, goat and cow milk-based formulas without added oligosaccharides impacted gut microbial activity and composition similarly to human milk. This suggests that even without supplementation of formula with oligosaccharides, whole goat milk, whole cow milk and cow milk ingredients already supply compounds in formulas that exert beneficial bifidogenic effects. Further clinical research is warranted to elucidate the effect of whole goat milk-based formulas on the infant gut microbiome.

Leptin signaling in vagal afferent neurons supports the absorption and storage of nutrients from high-fat diet

Objective:Activation of vagal afferent neurons (VAN) by postprandial gastrointestinal signals terminates feeding and facilitates nutrient digestion and absorption. Leptin modulates responsiveness of VAN to meal-related gastrointestinal signals. Rodents with high-fat diet (HF) feeding develop leptin resistance that impairs responsiveness of VAN. We hypothesized that lack of leptin signaling in VAN reduces responses to meal-related signals, which in turn decreases absorption of nutrients and energy storage from high-fat, calorically dense food.Methods:Mice with conditional deletion of the leptin receptor from VAN (Nav1.8-Cre/LepRfl/fl; KO) were used in this study. Six-week-old male mice were fed a 45% HF for 4 weeks; metabolic phenotype, food intake, and energy expenditure were measured. Absorption and storage of nutrients were investigated in the refed state.Results:After 4 weeks of HF feeding, KO mice gained less body weight and fat mass that WT controls, but this was not due to differences in food intake or energy expenditure. KO mice had reduced expression of carbohydrate transporters and absorption of carbohydrate in the jejunum. KO mice had fewer hepatic lipid droplets and decreased expression of de novo lipogenesis-associated enzymes and lipoproteins for endogenous lipoprotein pathway in liver, suggesting decreased long-term storage of carbohydrate in KO mice.Conclusions:Impairment of leptin signaling in VAN reduces responsiveness to gastrointestinal signals, which reduces intestinal absorption of carbohydrates and de novo lipogenesis resulting in reduced long-term energy storage. This study reveals a novel role of vagal afferents to support digestion and energy storage that may contribute to the effectiveness of vagal blockade to induce weight loss.

Elderberry (Sambucus nigra L.) Fruit Extract Alleviates Oxidative Stress, Insulin Resistance, and Inflammation in Hypertrophied 3T3-L1 Adipocytes and Activated RAW 264.7 Macrophages.

Oxidative stress and inflammation in hypertrophied adipose tissue with excessive fat accumulation play a crucial role in the development of obesity and accompanying metabolic dysfunctions. This study demonstrated the capacity of elderberry fruit (EDB) extract to decrease the elevated production of reactive oxygen species in hypertrophied 3T3-L1 adipocytes. Treatment with the EDB extract resulted in modulation of mRNA expression and protein secretion of key adipokines in hypertrophied adipocytes. Expression of leptin and adiponectin was, respectively, down- and up-regulated. Moreover, glucose uptake stimulation was noticed in mature adipocytes, both sensitive to insulin and insulin resistant. This may suggest a positive effect of EDB extract on insulin resistance status. The extract was also found to alleviate the inflammatory response in activated RAW 264.7 macrophages by down-regulating the expression of proinflammatory genes (TNF-α, IL-6, COX-2, iNOS) and suppressing the enhanced production of inflammatory mediators (TNF-α, IL-6, PGE2, NO). In vitro experiments showed that the EDB extract could inhibit digestive enzymes, including α-amylase, α-glucosidase, and pancreatic lipase, leading to reduced intestinal absorption of dietary lipids and carbohydrates. Further in vivo studies could be postulated to support EDB as a functional food component for the prevention and treatment of obesity and metabolic-immune comorbidities.

SGLT Inhibitors for Type 1 Diabetes: An Obvious Choice or Too Good to Be True?

In the recent past we have been fortunate to find new treatments based on entirely new mechanisms . . . or is that really so? The sodium–glucose cotransporter inhibitors (SGLTi) offer an instructive case in point. These apparently “ new” agents were preceded by phlorizin, a naturally occurring compound that has been used for physiologic studies for over 100 years (1). Given orally it interferes with intestinal absorption of carbohydrates and causes glucosuria. Studies in animal models of diabetes have provided useful insights, such as evidence that reduction of hyperglycemia can restore insulin sensitivity toward normal (2). However, phlorizin was considered unsuited for use by humans due to undesirable side effects. Recently its mechanism of action has been traced to effects on sodium–glucose cotransporters (SGLT) in the intestinal mucosa and the renal proximal tubule (3), and drugs with more nuanced effects on these transporters have been developed (4,5). These newer agents have greater affinity for SGLT2, which is expressed mainly in the kidney, and less for SGLT1, which facilitates intestinal absorption of glucose. Clinical effects of the newer SGLTi drugs in type 2 diabetes (T2D) include modest reductions of plasma glucose and A1C, weight, and blood pressure and are mediated in large part by glucosuria and sodium diuresis. These agents are taken once daily by mouth and do not require dose titration. Symptomatic side effects—mostly urinary or genital irritation or infections—are common but tolerated by most patients. Importantly, the new SGLTi drugs have highly desirable—and somewhat unexpected—cardiac and renal protective effects, as least in selected cohorts. Large trials of empagliflozin and canagliflozin, aiming to demonstrate safety in patients with T2D and high cardiovascular risk, have shown favorable effects on heart failure, cardiovascular death, and progression of albuminuria (6–9). Unwanted effects have been reported as well, including …

A proof-of-concept study to evaluate the efficacy and safety of BTI320 on post-prandial hyperglycaemia in Chinese subjects with pre-diabetes

BackgroundGalactomannan(s) are plant-derived fiber shown to reduce post-prandial blood glucose by delaying intestinal absorption of carbohydrates and slowing down gastric emptying. We examined glucose-lowering effects of BTI320, a propriety fractionated mannan(s) administered as a chewable tablet before meal in a proof-of-concept study in Chinese subjects with prediabetes.MethodsSixty Chinese adults aged 18–70 years with either impaired fasting glucose, impaired glucose tolerance, or glycated haemoglobin 5.7–6.4% (39-46 mmol/mol), were randomly assigned in 2:2:1 ratio to either BTI320 8 g (high dose), BTI320 4 g (low dose) or matching-placebo three times daily before meal for 16 weeks. The primary endpoint was change in fructosamine in subjects treated with BTI320 compared with placebo from baseline to week 4. Indices of glycaemic variability based on continuous glucose monitoring (CGM) and standard meal tolerance test were explored in secondary analyses.ResultsOf 60 subjects randomized, 3 subjects discontinued study treatment prematurely. In intention-to-treat analysis, no significant differences in change in serum fructosamine between low or high dose BTI320 and placebo were observed. Using random effect models, adjusted for variability by meals, treatment with low dose BTI320 was associated with reduction in 1-h (p < 0.01), 2-h (p = 0.01) and 3-h (p = 0.02) post-prandial incremental glucose area-under-curve and post-meal maximum glucose (p = 0.03) compared with placebo. Subjects receiving low dose BTI320 had greater body weight reduction than placebo group.ConclusionsBTI320 did not change fructosamine levels compared with placebo. BTI320 reduced glycaemic variability based on CGM indices.Trial registrationThe study was registered at www.clinicaltrials.gov, reference number NCT02358668 (9 February 2015).

Acute Post-Prandial Cognitive Effects of Brown Seaweed Extract in Humans.

(Poly)phenols and, specifically, phlorotannins present in brown seaweeds have previously been shown to inhibit α-amylase and α-glucosidase, key enzymes involved in the breakdown and intestinal absorption of carbohydrates. Related to this are observations of modulation of post-prandial glycemic response in mice and increased insulin sensitivity in humans when supplemented with seaweed extract. However, no studies to date have explored the effect of seaweed extract on cognition. The current randomized, placebo-controlled, double-blind, parallel groups study examined the impact of a brown seaweed extract on cognitive function post-prandially in 60 healthy adults (N = 30 per group). Computerized measures of episodic memory, attention and subjective state were completed at baseline and 5 times at 40 min intervals over a 3 h period following lunch, with either seaweed or placebo consumed 30 min prior to lunch. Analysis was conducted with linear mixed models controlling for baseline. Seaweed led to significant improvements to accuracy on digit vigilance (p = 0.035) and choice reaction time (p = 0.043) tasks. These findings provide the first evidence for modulation of cognition with seaweed extract. In order to explore the mechanism underlying these effects, future research should examine effects on cognition in parallel with blood glucose and insulin responses.

Effectiveness of three commonly used transition phase diets in the inpatient management of children with severe acute malnutrition: a pilot randomized controlled trial in Malawi

BackgroundThe case fatality rate of severely malnourished children during inpatient treatment is high and mortality is often associated with diarrhea. As intestinal carbohydrate absorption is impaired in severe acute malnutrition (SAM), differences in dietary formulations during nutritional rehabilitation could lead to the development of osmotic diarrhea and subsequently hypovolemia and death. We compared three dietary strategies commonly used during the transition of severely malnourished children to higher caloric feeds, i.e., F100 milk (F100), Ready-to-Use Therapeutic Food (RUTF) and RUTF supplemented with F75 milk (RUTF + F75).MethodsIn this open-label pilot randomized controlled trial, 74 Malawian children with SAM aged 6–60 months, were assigned to either F100, RUTF or RUTF + F75. Our primary endpoint was the presence of low fecal pH (pH ≤ 5.5) measured in stool collected 3 days after the transition phase diets were introduced. Secondary outcomes were duration of hospital stay, diarrhea and other clinical outcomes. Chi-square test, two-way analysis of variance and logistic regression were conducted and, when appropriate, age, sex and initial weight for height Z-scores were included as covariates.ResultsThe proportion of children with acidic stool (pH ≤5.5) did not significantly differ between groups before discharge with 30, 33 and 23% for F100, RUTF and RUTF + F75, respectively. Mean duration of stay after transitioning was 7.0 days (SD 3.4) with no differences between the three feeding strategies. Diarrhea was present upon admission in 33% of patients and was significantly higher (48%) during the transition phase (p < 0.05). There was no significant difference in mortality (n = 6) between diets during the transition phase nor were there any differences in other secondary outcomes.ConclusionsThis pilot trial does not demonstrate that a particular transition phase diet is significantly better or worse since biochemical and clinical outcomes in children with SAM did not differ. However, larger and more tightly controlled efficacy studies are needed to confirm these findings.Trial registrationISRCTN13916953 Registered: 14 January 2013.

Inhibitory Effects of Oncoba spinosa on Key Enzymes Related to Diabetes Mellitus (A-Amylase and A-Glucosidase) and Obesity (Pancreatic Lipase) in Vitro

Aim and Objective: Oncoba spinosa Forssk. (Flacourtiaceae) (OS) is traditionally used for the management of diabetes mellitus. In previous studies, we studied the effect of OS on α-amylase and α-glucosidase inhibition, however the effect of OS on pancreatic lipase inhibition and kinetics of α-amylase, α-glucosidase and pancreatic lipase inhibition were not studied. This study determined the in vitro inhibitory effects of OS against pancreatic lipase and characterized the kinetics of α-amylase, α-glucosidase and pancreatic lipase inhibition. Materials and Methods: Dried powdered roots were successively extracted with various solvents such as petroleum ether, chloroform, ethyl acetate, and 70% ethanol. The successive extracts obtained (62.5-1000 μg/ml) were subjected to in vitro pancreatic lipase inhibitory assay and the most active extract was selected for kinetic studies. Results: Of all the successive extracts studied, the ethanolic extract showed highest pancreatic lipase inhibitory activity. The ethanolic extract showed mixed type of inhibition against α-amylase and pancreatic lipase whereas noncompetitive inhibition against α-glucosidase. Conclusion: The data of this study suggests that OS inhibits amylase, glucosidase and lipase activities, which leads to a reduction in the intestinal absorption of carbohydrates and lipids.

Effect of Oral Insulin on the Development of Small Intestine Carbohydrate Hydrolysis and Absorption in Suckling Rats

The study is conducted to reveal the effect of oral insulin on the development of carbohydrate hydrolysis and transport in the small intestine in suckling rats. Oral insulin administration (5 U/kg/day) from the 1st to the 21st day of postnatal life resulted in induction of the carbohydrate assimilation in the small intestine of growing rats. Oral insulin increased intestinal maltase, sucrase and lactase activity as well as absorption of free and hydrolysis-dependent glucose from maltose in the small intestine of suckling rats. The effect was age-dependent and was clearly expressed during the second half of the milk nutrition period. After weaning oral insulin effect on the intestinal carbohydrate digestion and absorption was absent. These data show oral insulin keeps its biological activity in the intestinal cavity and they suggest involvement of milk insulin in the hydrolysis and absorption of carbohydrates in the small intestine.

Effect of Dietary Purified Xanthohumol from Hop (Humulus lupulus L.) Pomace on Adipose Tissue Mass, Fasting Blood Glucose Level, and Lipid Metabolism in KK-Ay Mice.

We previously showed that xanthohumol-rich hop extract (XRHE, ~18% xanthohumol) exerts anti-obesity effects in rats fed a high-fat diet through regulation of fatty acid metabolism. In this study, we examined the effects of dietary purified xanthohumol from XRHE (PX, ~91.9% xanthohumol) in KK-Ay mice in order to understand the anti-obesity effects of xanthohumol alone because XRHE contains 82% unknown compounds. Dietary consumption of PX significantly inhibited an increase in the visceral fat weight of mice compared to those fed control diet without PX. Plasma leptin level was significantly lower in the PX-fed group than in the control group. Dietary PX lowered hepatic fatty acid synthesis by down-regulation of SREBP1c mRNA expression in the liver. On the other hand, fatty acid β-oxidation in the liver was promoted by dietary PX through the up-regulation of PPARα mRNA expression. Moreover, the fecal levels of fatty acids and carbohydrates increased by dietary PX. PX inhibited lipase or α-amylase activity in vitro. Thus, we found that PX may exert anti-obesity effects through the regulation of lipid metabolism and inhibition of intestinal fat and carbohydrate absorption, and that xanthohumol alone may exert anti-obesity effects.

Single-dose acarbose decreased glucose-dependent insulinotropic peptide and glucagon levels in Chinese patients with newly diagnosed type 2 diabetes mellitus after a mixed meal.

BackgroundAcarbose slows down the intestinal absorption of carbohydrates, but its effects on the secretion of incretins are still poorly known. This study aimed to examine the effects of single-dose acarbose on the secretion of incretins in patients with newly diagnosed type 2 diabetes mellitus (T2DM).MethodsIn this pilot study, twenty-three patients diagnosed with T2DM were randomly assigned to the oral glucose tolerance test (OGTT) group (n = 11) and the mixed meal test (MMT) group (n = 12). Fourteen subjects with normal OGTT were included as controls. Plasma glucose, insulin, glucagon, glucagon-like peptide-1 (GLP-1), and glucose-dependent insulinotropic peptide (GIP) were measured at 0 (fasting), 15, 30, 60, 90, and 120 min after nutrient load. A week later, controls underwent MMT, the OGTT group underwent OGTT receiving 100 mg acarbose, and the MMT group underwent MMT receiving 100 mg acarbose. The same blood markers were measured again.ResultsNo significant difference was observed in the OGTT group before and after administering acarbose. In the MMT group, postprandial levels of glucose (P < 0.01), insulin (P < 0.01), glucagon at 15 min (P < 0.05), glucagon area under the curve (AUC) (P < 0.05), GIP levels at 30 min (P < 0.05), and GIP AUC (P < 0.05) were decreased after receiving acarbose with a mixed meal, but GLP-1 levels and GLP-1 AUC did not change.ConclusionsSingle-dose acarbose could reduce the secretion of GIP and glucagon after a mixed meal in patients with newly diagnosed T2DM. The influence of acarbose on incretin levels could be related to the types of carbohydrate being consumed.Trial registrationThis study was registered with the Chinese Clinical Trial Registry (Registration Number: ChiCTR-TRC-14004260, Date of Registration: 2014-01-19).

Do dietary supplements for weight loss work?

also reduce caloric intake, food ingestion rate, and nutrient absorption due to its soluble fi ber backbone. Glucomannan’s effect on satiety is the result of its fi ber content; it was associated with a modest weight loss of 5 pounds in 8 weeks, according to a November 2005 study published in Alternative Therapies in Health and Medicine (http:// apha.us/ZVeaAG). A slight decrease in total cholesterol and triglyceride concentrations may occur with the use of glucomannan, although similar results may be obtained with a high-fi ber diet. Sensa is another popular weight loss product heavily promoted to consumers. Invented by neurologist Alan Hirsch, the product is based on the central mechanisms that regulate satiety. Sensa’s manufacturers claim that when it is sprinkled on food, it enhances the smell and taste of the food and, as a result, the feeling of satiety. There has been no evidence documenting the effi cacy of Sensa for signifi cant weight loss or maintenance of weight loss published in peer-reviewed journals, however. White kidney bean (Phaseolus vulgaris) extract (WKBE) acts as an inhibitor of alpha amylase, resulting in decreased digestion and intestinal absorption of carbohydrates. In Diabetes, Metabolic Syndrome, and Obesity: Targets and Therapy, researchers reported a reduction in postprandial blood glucose with WKBE, which may be helpful for patients with type 2 diabetes (http:// apha.us/15i8baA). The best results occurred when WKBE was taken with meals containing large amounts of carbohydrates. The product may delay gastric emptying, thus simulating the feeling of satiety, and resulting in weight loss. WKBE should not contain phytohemagglutinin, a toxic protein found in P. vulgaris. Products should have a hemagglutinating activity less than 700 units/g and trypsin inhibiting activity less than 20 units/g (dry weight), according to a review published in Nutrition Journal (http://apha.us/ZNt3DC). Raspberry ketone, present in raspberries, cranberries, and blackberries, has a structure similar to capsaicin and synephrine. Researchers have theorized that capsaicin enhances thermogenesis, resulting in increased energy expenditure. There are limited data on the safety and effi cacy of synephrine, an alpha-adrenergic agonist, as an alternative to ephedra, and it may increase blood pressure. In a 2010 study published in Planta Medica, raspberry ketone, when fed to male mice in high dosages, prevented high-fat diet–induced increase in weight, stimulated lipolysis in white adipocytes, and increased expression of adiponectin. Bitter orange, Citrus aurantium, has been proposed to work similarly to raspberry ketone because it includes synephrine, N-methyltyramine, and furocoumarins. The product is believed to increase metabolism and suppress appetite, but evidence on its safety and effi cacy is limited. Fainting, heart attacks, and strokes in otherwise healthy people have been reported with bitter orange alone or in combination with caffeine.

Dietary intake of green tea polyphenols regulates insulin sensitivity with an increase in AMP‐activated protein kinase α content and changes in mitochondrial respiratory complexes

The intake of food rich in polyphenols is related to a lower incidence in almost all chronic degenerative diseases. However, relatively little is known about the molecular mechanisms involved in its antioxidant properties. The aim of this study was to determine whether the mechanism of action of polyphenols could be related to a modulation in energy uptake and metabolism, and further induced mitochondrial changes. For this purpose, male C57BL6 mice were fed during 3 months with a tea-based beverage rich in polyphenols. Insulin sensitivity, tissue oxidative damage biomarkers, as well as energy-related signaling pathways were determined to evaluate its mechanism of action. As a result, a tissue- and protein-specific subtle reduction in oxidative damage was observed. Skeletal muscle showed mitochondrial changes in respiratory complexes and an increase in AMP-activated protein kinase α levels, suggesting reduced energy availability. These changes were also associated with adipose tissue cellular metabolism. This was confirmed by a decline in the potential of energy uptake, evidenced by a diminished intestinal and systemic absorption of carbohydrates together with an inhibition of insulin sensitivity. Our results suggest that the mechanisms of action of green tea polyphenols may be related to their ability to modulate energy uptake leading to mitochondrial adaptations possibly responsible for the changes in protein oxidative damage.

Quality assessment and anti-obesity activity of Stellaria media (Linn.) Vill

BackgroundObesity is recognized as a social problem, associated with serious health risks and increased mortality. Numerous trials have been conducted to find and develop new anti-obesity drugs through herbal sources to minimize side effects associated with the present anti-obesity drugs. The present study was designed to evaluate the quality control parameters, quantitative phytochemical analysis (total phenolic, total flavonoids and total saponin content), and the anti-obesity effect of lyophilized juice (LJ) of Stellaria media (Linn.) Vill. by employing in vitro and in vivo models.MethodsIn vitro studies were performed to evaluate the inhibitory activity of LJ on pancreatic amylase and lipase. The in vivo pancreatic lipase activity was evaluated by measurement of plasma triacylglycerol levels after oral administration of lipid emulsion to swiss albino mice. Furthermore, the anti-obesity effect of LJ was assessed at two doses, 400 mg/kg and 900 mg/kg body weight in mice fed a high-fat-diet with or without LJ for 6 weeks.ResultsThe LJ inhibited pancreatic amylase and lipase activity in vitro and elevated plasma triacylglycerol level in mice. LJ suppressed the increase in body weight, retroperitoneal adipose tissue, liver weights and serum parameters viz., total cholesterol, total triglyceride, LDL-cholesterol level at the dose of 900 mg/kg body weight of the mice fed with high fat diet. The total phenolic, flavonoid and saponin contents were found to be 0.26 mg/g, 1.4 mg/g and 1.19 μg/g respectively of LJ.ConclusionThe anti-obesity effects of LJ in high-fat-diet fed mice may be partly mediated through delaying the intestinal absorption of dietary fat and carbohydrate by inhibiting digestive enzymes.

Evaluation of sucromalt digestion in healthy children using breath hydrogen as a biomarker of carbohydrate malabsorption

The measurement of hydrogen in exhaled breath is widely accepted as a non-invasive yet efficient means to evaluate carbohydrate malabsorption. Hydrogen is not normally produced by mammalian cells and its appearance in breath indicates incomplete small intestinal carbohydrate absorption with subsequent breakdown of the carbohydrate by anaerobic bacteria in the colon. This study was undertaken to evaluate the absorption of a novel, slowly digestible carbohydrate sweetener, sucromalt. Two experiments occurred approximately 2 weeks apart with the participants randomly consuming one of two test foods on each visit. Following baseline breath hydrogen measurements, healthy 8-10 year-old children (n = 10) consumed a yogurt breakfast containing either 15 g of inulin (positive control) or 30 g of sucromalt. Every 15 min during the next 6 h, samples of exhaled breath were taken from each participant for hydrogen content analysis, thereby establishing 24 total data points. Participants' 6 h breath hydrogen responses were plotted against their baseline measurement and appropriate statistical evaluations were applied to the data. Following ingestion of inulin, breath hydrogen stayed near baseline for approximately 2 h but rose rapidly thereafter to a steady state of 20-30 ppm, which continued to the end of the study period. In contrast, exhaled hydrogen following sucromalt ingestion remained at or near baseline for the entire 6 h test period. A significantly higher level of hydrogen was exhaled with inulin ingestion compared to sucromalt (incremental area under the curve, p = 0.002). Results indicated complete absorption of sucromalt's saccharide constituents in children.

Delayed enteral feeding impairs intestinal carbohydrate absorption in critically ill patients

Delayed enteral feeding impairs intestinal carbohydrate absorption in critically ill patients