Consuming fructose-sweetened beverages increases body adiposity in mice

The Effect of Boric Acid on Oxidative Stress, Inflammation, and Apoptosis in Embryonic and Fetal Tissues Damage Caused by Consumption of High-Fructose Corn Syrup in Pregnant Rats

This study aimed to determine the protective role of boric acid in a pregnant rat model of high fructose corn syrup consumption. Consumption of high fructose corn syrup has been associated with adverse health outcomes in humans and animals. Twenty-eight healthy female Wistar albino rats (250-300 g weight and 16-24 weeks old) were randomly distributed into four equal groups (n = 7): Control, Boric acid (BA), High Fructose Corn Syrup (HFCS), HFCS + BA. Boric acid (20 mg/kg) was administered to pregnant rats via oral gavage every day during pregnancy. The prepared 30% HFCS (F30) solution (24% fructose, 28% dextrose) was added to the drinking water throughout pregnancy. At the end of pregnancy (day 19), blood, placenta, uterus, and fetuses were collected from rats. The results indicated that HFCS increases oxidative stress by increasing the level of MDA and decreasing GSH, SOD, and CAT activity in the blood of maternal. However, BA administration significantly decreased MDA levels and increased GSH levels, SOD, and CAT activity (p < 0.05). In addition, HFCS consumption significantly increased plasma TNF-α, IL-6, and leptin levels compared to control, BA, and HFCS + BA groups (p < 0.05). However, BA administration significantly decreased plasma TNF-α, IL-6, and leptin levels (p < 0.05). Furthermore, BA (20 mg/kg) significantly decreased HFCS-induced histopathological and immunohistochemical alterations in the placenta, uterus, and fetal tissue. In conclusion, BA may prevent HFCS toxicity in maternal and fetal tissues, as it regulates oxidative imbalance in pregnant rat and alleviates histopathological and immunohistochemical changes. The findings indicate a need for further studies to assess the potential of boron in preventing or mitigating the effects of HFCS during pregnancy.

Dietary Influences on Gut Microbiota and Their Role in Metabolic Dysfunction-Associated Steatotic Liver Disease (MASLD)

Metabolic dysfunction-associated steatotic liver disease (MASLD) is a major contributor to liver-related morbidity, cardiovascular disease, and metabolic complications. Lifestyle interventions, including diet and exercise, are first line in treating MASLD. Dietary approaches such as the low-glycemic-index Mediterranean diet, the ketogenic diet, intermittent fasting, and high fiber diets have demonstrated potential in addressing the metabolic dysfunction underlying this condition. The development and progression of MASLD are closely associated with taxonomic shifts in gut microbial communities, a relationship well-documented in the literature. Given the importance of diet as a primary treatment for MASLD, it is important to understand how gut microbiota and their metabolic byproducts mediate favorable outcomes induced by healthy dietary patterns. Conversely, microbiota changes conferred by unhealthy dietary patterns such as the Western diet may induce dysbiosis and influence steatotic liver disease through promoting hepatic inflammation, up-regulating lipogenesis, dysregulating bile acid metabolism, increasing insulin resistance, and causing oxidative damage in hepatocytes. Although emerging evidence has identified links between diet, microbiota, and development of MASLD, significant gaps remain in understanding specific microbial roles, metabolite pathways, host interactions, and causal relationships. Therefore, this review aims to provide mechanistic insights into the role of microbiota-mediated processes through the analysis of both healthy and unhealthy dietary patterns and their contribution to MASLD pathophysiology. By better elucidating the interplay between dietary nutrients, microbiota-mediated processes, and the onset and progression of steatotic liver disease, this work aims to identify new opportunities for targeted dietary interventions to treat MASLD efficiently.

Long-term metabolic effects of non-nutritive sweeteners

OBJECTIVE

Excessive consumption of added sugars has been linked to the rise in obesity and associated metabolic abnormalities. Non-nutritive sweeteners (NNSs) offer a potential solution to reduce sugar intake, yet their metabolic safety remains debated. This study aimed to systematically assess the long-term metabolic effects of commonly used NNSs under both normal and obesogenic conditions.

METHODS

To ensure consistent sweetness level and controlling for the acceptable daily intake (ADI), eight weeks old C57BL/6 male mice were administered with acesulfame K (ace K, 535.25 mg/L), aspartame (411.75 mg/L), sucralose (179.5 mg/L), saccharin (80 mg/L), or steviol glycoside (Reb M, 536.25 mg/L) in the drinking water, on the background of either regular or high-fat diets (in high fat diet 60% of calories from fat). Water or fructose-sweetened water (82.3.gr/L), were used as controls. Anthropometric and metabolic parameters, as well as microbiome composition, were analyzed following 20-weeks of exposure.

RESULTS

Under a regular chow diet, chronic NNS consumption did not significantly affect body weight, fat mass, or glucose metabolism as compared to water consumption, with aspartame demonstrating decreased glucose tolerance. In diet-induced obesity, NNS exposure did not increase body weight or alter food intake. Exposure to sucralose and Reb M led to improved insulin sensitivity and decreased weight gain. Reb M specifically was associated with increased prevalence of colonic Lachnospiracea bacteria.

CONCLUSIONS

Long-term consumption of commonly used NNSs does not induce adverse metabolic effects, with Reb M demonstrating a mild improvement in metabolic abnormalities. These findings provide valuable insights into the metabolic impact of different NNSs, aiding in the development of strategies to combat obesity and related metabolic disorders.

Partial validation of a six-month high-fat diet and fructose-glucose drink combination as a mouse model of nonalcoholic fatty liver disease

PURPOSE

The need to investigate the pathogenesis and treatment of nonalcoholic fatty liver disease (NAFLD) has led to the development of multiple mouse models. The aim of this study was to validate a fast food diet (FFD) mouse model that is introduced as being close to the human disease.

METHODS

Eight to nine weeks old male and female C57BL/6 J mice were randomly allocated to a FFD group or to a chow diet (CD) group. Every four weeks, mice were weighed, and blood samples were collected for the measurement of glucose, alanine aminotransferase (ALT), aspartate aminotransferase (AST), triglycerides (TGs) and total cholesterol. After 25 weeks, mice were sacrificed, and liver tissue was histologically evaluated.

RESULTS

FFD mice gained more weight (p = 0.049) and presented a higher liver-to-body weight ratio (p < 0.001) compared to CD mice. FFD group presented with greater steatosis, hepatocellular ballooning and NAFLD activity score (NAS), whereas lobular inflammation and fibrosis were not significantly different compared to CD. When stratified by sex, NAS was different between FFD and CD groups in both male and female mice. Group by time interaction was significant for weight, ALT and cholesterol, but not for glucose, AST and TGs.

CONCLUSION

FFD mice presented with morphologic and biochemical features of NAFLD and with greater hepatic steatosis, hepatocellular ballooning and NAS, but not lobular inflammation and fibrosis, compared to CD mice. These results only partly validate the FFD mouse model for NAFLD, at least for a 6-month feeding period.

Pomegranate supplementation alleviates dyslipidemia and the onset of non-alcoholic fatty liver disease in Wistar rats by shifting microbiota and producing urolithin-like microbial metabolites

Non-alcoholic fatty liver disease (NAFLD), obesity and related chronic diseases are major non-communicable diseases with high mortality rates worldwide. While dietary sugars are known to be responsible for insulin resistance and metabolic syndrome (MetS), the underlying pathophysiological effects of sustained fructose consumption require further elucidation. We hypothesize that certain bioactive compounds (i.e. punicalagin and ellagic acid) from dietary pomegranate could counteract the harmful effects of sustained fructose consumption in terms of obesity and liver damage. The present study aimed to elucidate both the molecular mechanisms involved in the pathophysiology associated with fructose intake and the effect of a punicalagin-rich commercial pomegranate dietary supplement (P) used as a nutritional strategy to alleviate fructose-induced metabolic impairments. Thus, nineteen Wistar rats fed on a basal commercial feed were supplemented with either 30% (w/v) fructose in drinking water (F; n = 7) or 30% (w/v) fructose solution plus 0.2% (w/v) P (F + P; n = 6) for 10 weeks. The results were compared to those from a control group fed on the basal diet and provided with drinking water (C; n = 6). Body weight and energy intake were registered weekly. P supplementation decreased fat depots, counteracted the dyslipidemia caused by F and improved markers of liver injury including steatosis. The study of the microbiota by metagenomics and urine by untargeted MS-based metabolomics revealed microbial metabolites from P that may be responsible for these health benefits.

Regulation of Fructose Metabolism in Nonalcoholic Fatty Liver Disease

Elevations in fructose consumption have been reported to contribute significantly to an increased incidence of obesity and metabolic diseases in industrial countries. Mechanistically, a high fructose intake leads to the dysregulation of glucose, triglyceride, and cholesterol metabolism in the liver, and causes elevations in inflammation and drives the progression of nonalcoholic fatty liver disease (NAFLD). A high fructose consumption is considered to be toxic to the body, and there are ongoing measures to develop pharmaceutical therapies targeting fructose metabolism. Although a large amount of work has summarized the effects fructose exposure within the intestine, liver, and kidney, there remains a gap in our knowledge regarding how fructose both indirectly and directly influences immune cell recruitment, activation, and function in metabolic tissues, which are essential to tissue and systemic inflammation. The most recent literature demonstrates that direct fructose exposure regulates oxidative metabolism in macrophages, leading to inflammation. The present review highlights (1) the mechanisms by which fructose metabolism impacts crosstalk between tissues, nonparenchymal cells, microbes, and immune cells; (2) the direct impact of fructose on immune cell metabolism and function; and (3) therapeutic targets of fructose metabolism to treat NAFLD. In addition, the review highlights how fructose disrupts liver tissue homeostasis and identifies new therapeutic targets for treating NAFLD and obesity.

Gut commensal Kineothrix alysoides mitigates liver dysfunction by restoring lipid metabolism and gut microbial balance

Metabolic dysfunction-associated steatotic liver disease (MASLD), previously known as Non-Alcoholic Fatty Liver Disease, is a widespread liver condition characterized by excessive fat buildup in hepatocytes without significant alcohol consumption. Manipulation of the gut microbiome has been considered to prevent and improve the occurrence and progression of MASLD, particularly through the gut-liver axis. This study aimed to investigate the correlation between the gut microbiome and liver function and determine whether the gut microbiome can ameliorate MASLD. We comparatively analyzed the gut microbiome composition between mice fed normal chow and those fed a high-fat diet and observed that the abundance of Kineothrix alysoides decreased in the high-fat group. Further analysis showed that treatment with K. alysoides in the high-fat diet group led to decreased weight loss, and MASLD attenuation. Importantly, K. alysoides treatment attenuated MASLD in mice fed a high-fat, high-fructose diet (HFHF), which can cause advanced liver damage. Furthermore, administration of K. alysoides altered the gut microbial composition in the HFHF diet group and improved MASLD. Overall, these findings demonstrate the potential of K. alysoides in restoring gut health and facilitating lipid metabolism to prevent and treat MASLD.

Dysregulation of Lipid and Glucose Metabolism in Nonalcoholic Fatty Liver Disease

Non-Alcoholic Fatty Liver Disease (NAFLD) is a highly prevalent condition affecting approximately a quarter of the global population. It is associated with increased morbidity, mortality, economic burden, and healthcare costs. The disease is characterized by the accumulation of lipids in the liver, known as steatosis, which can progress to more severe stages such as steatohepatitis, fibrosis, cirrhosis, and even hepatocellular carcinoma (HCC). This review focuses on the mechanisms that contribute to the development of diet-induced steatosis in an insulin-resistant liver. Specifically, it discusses the existing literature on carbon flux through glycolysis, ketogenesis, TCA (Tricarboxylic Acid Cycle), and fatty acid synthesis pathways in NAFLD, as well as the altered canonical insulin signaling and genetic predispositions that lead to the accumulation of diet-induced hepatic fat. Finally, the review discusses the current therapeutic efforts that aim to ameliorate various pathologies associated with NAFLD.

Effects of coconut oil long-term supplementation in Wistar rats during metabolic syndrome - regulation of metabolic conditions involving glucose homeostasis, inflammatory signals, and oxidative stress

This study was designed to evaluate the long-term effects of Fructose (20%) feeding in rats, simulating metabolic syndrome (MetS), and the effects of coconut oil (C.O.) supplementation when administered in a MetS context. MetS is a cluster of systemic conditions that represent an increased chance of developing cardiovascular diseases and type 2 diabetes in the future. C.O. has been the target of media speculation, and recent studies report inconsistent results. C.O. improved glucose homeostasis and reduced fat accumulation in Fructose-fed rats while decreasing the levels of triglycerides (TGs) in the liver. C.O. supplementation also increased TGs levels and fructosamine in serum during MetS, possibly due to white adipose tissue breakdown and high fructose feeding. Pro-inflammatory cytokines IL-1β and TNF-α were also increased in rats treated with Fructose and C.O. Oxidative stress marker nitrotyrosine is increased in fructose-fed animals, and C.O. treatment did not prevent this damage. No significant changes were observed in lipoperoxidation marker 4-Hydroxynonenal; however, fructose feeding increased total conjugated dienes and caused conjugated dienes to switch their conformation from cis-trans to trans-trans, which was not prevented by C.O. treatment. Potential benefits of C.O. have been reported with inconsistent results, and indeed we observed some benefits of C.O. supplementation in aiding weight loss, fat accumulation, and improving glucose homeostasis. Nonetheless, we also demonstrated that long-term C.O. supplementation could present some problematic effects with higher risk for individuals suffering MetS, including increased TGs and fructosamine levels and conformational changes in dienes.

AMPK activation by AICAR reduces diet induced fatty liver in C57BL/6 mice

Dysregulation of 5'-adenosine monophosphate-activated protein kinase (AMPK) occurs in metabolic disorders including non-alcoholic fatty liver disease (NAFLD) which makes it a molecular target for treatment. An AMPK activator, 5-aminoimidazole-4-carboxamide-1-β-D-ribofuranoside (AICAR) alleviates NAFLD in experimental rats, however the specific mechanism remains to be explored. We aimed to study the effect of AICAR on lipid levels, oxidant-antioxidant balance, AMPK and mTOR activation and FOXO3 gene expression in liver of mice model. Fatty liver was induced in two groups of C57BL/6 mice (groups 2 and 3) by providing a high fat high fructose diet (HFFD) for 10 weeks while groups 1 and 4 animals were fed normal pellet. For the last two weeks, groups 3 and 4 were administered AICAR (150 mg/kg bw/day, i.p.) while groups 1 and 2 were administered saline. AICAR decreased fatty liver, decreased glucose and insulin in circulation, prevented the accumulation of triglycerides and collagen and ameliorated oxidative stress in HFFD fed mice. At the molecular level, AICAR upregulated FOXO3 and p-AMPK expression and reduced p-mTOR expression. AMPK activation may involve FOXO3 in protection against NAFLD. The role of AMPK, mTOR and FOXO3 crosstalk in NAFLD needs to be characterised in future.

Effects of Maternal High-Fructose Diet on Long Non-Coding RNAs and Anxiety-like Behaviors in Offspring

Increased fructose intake is an international issue. A maternal high-fructose diet during gestation and lactation could affect nervous system development in offspring. Long non-coding RNA (lncRNA) plays an important role in brain biology. However, the mechanism whereby maternal high-fructose diets influence offspring brain development by affecting lncRNAs is still unclear. Here, we administered 13% and 40% fructose water to establish a maternal high-fructose diet model during gestation and lactation. To determine lncRNAs and their target genes, full-length RNA sequencing was performed using the Oxford Nanopore Technologies platform, and 882 lncRNAs were identified. Moreover, the 13% fructose group and the 40% fructose group had differentially expressed lncRNA genes compared with the control group. Enrichment analyses and co-expression analyses were performed to investigate the changes in biological function. Furthermore, enrichment analyses, behavioral science experiments, and molecular biology experiments all indicated that the fructose group offspring showed anxiety-like behaviors. In summary, this study provides insight into the molecular mechanisms underlying maternal high-fructose diet-induced lncRNA expression and co-expression of lncRNA and mRNA.

Impact of dietary sucralose and sucrose-sweetened water intake on lipid and glucose metabolism in male mice

AIMS

Overconsumption of sugar-sweetened beverages (SSBs) is associated with an increased risk of metabolic disorders, including obesity and diabetes. However, accumulating evidence also suggests the potential negative impact of consuming nonnutritive sweeteners (NNSs) on weight and glycaemic control. The metabolic effects of sucralose, the most widely used NNS, remain controversial. This study aimed to compare the impact of intake of dietary sucralose (acceptable daily intake dose, ADI dose) and sucrose-sweetened water (at the same sweetness level) on lipid and glucose metabolism in male mice.

MATERIALS AND METHODS

Sucralose (0.1 mg/mL) or sucrose (60 mg/mL) was added to the drinking water of 8-week-old male C57BL/6 mice for 16 weeks, followed by oral glucose and intraperitoneal insulin tolerance tests, and measurements of bone mineral density, plasma lipids, and hormones. After the mice were sacrificed, the duodenum and ileum were used for examination of sweet taste receptors (STRs) and glucose transporters.

RESULTS

A significant increase in fat mass was observed in the sucrose group of mice after 16 weeks of sweetened water drinking. Sucrose consumption also led to increased levels of plasma LDL, insulin, lipid deposition in the liver, and increased glucose intolerance in mice. Compared with the sucrose group, mice consuming sucralose showed much lower fat accumulation, hyperlipidaemia, liver steatosis, and glucose intolerance. In addition, the daily dose of sucralose only had a moderate effect on T1R2/3 in the intestine, without affecting glucose transporters and plasma insulin levels.

CONCLUSION

Compared with mice consuming sucrose-sweetened water, daily drinking of sucralose within the ADI dose had a much lower impact on glucose and lipid homeostasis.

Camel milk protein hydrosylate alleviates hepatic steatosis and hypertension in high fructose-fed rats

CONTEXT

Camel milk is used in traditional medicine to treat diabetes mellitus hypertension and other metabolic disorders.

OBJECTIVE

This study evaluated the antisteatotic and antihypertensive effects of camel milk protein hydrolysate (CMH) in high fructose (HF)-fed rats and compared it with the effects afforded by the intact camel milk protein extract (ICM).

MATERIALS AND METHODS

Adult male Wistar rats were divided into 6 groups (n = 8 each) as 1) control, 2) ICM (1000 mg/kg), 3) CMH (1000 mg/kg), 4) HF (15% in drinking water), 5) HF (15%) + ICM (1000 mg/kg), and 6) HF (15%) + CMH (1000 mg/kg). All treatments were given orally for 21 weeks, daily.

RESULTS

Both ICM and CMH reduced fasting glucose and insulin levels, serum and hepatic levels of cholesterol and triglycerides, and serum levels of ALT and AST, angiotensin II, ACE, endothelin-1, and uric acid in HF-fed rats. In addition, both ICM and CMH reduced hepatic fat deposition in the hepatocytes and reduced hepatocyte damage. This was associated with an increase in the hepatic activity of AMPK, higher PPARα mRNA, reduced expression of fructokinase C, SREBP1, SREBP2, fatty acid synthase, and HMG-CoA-reductase. Both treatments lowered systolic and diastolic blood pressure. However, the effects of CMH on all these parameters were greater as compared to ICM.

DISCUSSION AND CONCLUSIONS

The findings of this study encourage the use of CMH in a large-scale population and clinical studies to treat metabolic steatosis and hypertension.

The effect of evening primrose oil (Oenothera biennis) on the level of adiponectin and some biochemical parameters in rats with fructose induced metabolic syndrome

The effect of evening primrose oil on adiponectin level and some biochemical parameters in model of fructose-induced metabolic syndrome were investigated. The rats were divided into 4 groups: control, evening primrose oil, fructose, fructose + evening primrose oil. Body weight, daily feed and water consumptions and systolic blood pressures of animals were measured. At the end of trial, blood samples were taken, livers were excised and histopathological examination was performed. Glucose, uric acid, triglyceride, T.cholesterol, LDL, HDL, VLDL, ALT, AST, ALP, LDH, adiponectin, insulin, IL-6, TNF-α, TAC, and TOS levels were analysed. Some analysed parameters and systolic blood pressure of fructose + evening primrose oil group decreased significantly compared to fructose group and adiponectin, TAC, and HDL levels were significantly increased. As conclusion, evening primrose oil can be considered as antioxidant agent by reducing oxidative stress, increasing adiponectin levels and insulin sensitivity, anti-inflammatory properties, exhibiting anti-atherogenic effect by regulating dyslipidemia and systolic blood pressure.

Comparison of oral administration of fructose and glucose on food intake and physiological parameters in broiler chicks

Like glucose, fructose is a monosaccharide, but the mechanisms of its absorption and metabolism in the body are very different between the 2 molecules. In this study, we investigated the effects of oral administration of glucose and fructose on food intake, diencephalic gene expression, and plasma metabolite concentrations in broiler chicks. The animals used in this study were 4-day-old male broiler chicks (Ross 308). They were given glucose, fructose (200 mg/ 0.5 mL/ bird), or a similar volume of distilled water orally after 6 h fasting. After treatment, measurements of food intake (at 0, 30, and 60 min), and blood glucose as well as insulin concentrations were measured over time; however, diencephalic (hypothalamus) gene expression and plasma metabolites were measured at 30 min. The results showed that glucose administration suppressed food intake, but fructose administration did not suppress food intake and it was at the same level as distilled water administration. In addition, fructose administration did not increase plasma glucose and insulin levels as did glucose administration. In the diencephalon, expression levels of genes related to the melanocortin system were unaffected by the treatment, while gene expression levels related to intracellular energy regulation, such as AMP-activated protein kinase were affected by the glucose treatment in the fasted chicks. These results suggest that fructose administration does not suppress feeding behavior as a result of possible reduction in the energy levels in the diencephalon and associated energy metabolism.

Prolonged Consumption of glucose syrup enhances glucose tolerance in mice

There is debate about the metabolic impact of sugar-sweetened beverages. Here, we tested the hypothesis that ad lib consumption of glucose (Gluc) or high-fructose (HiFruc) syrups improves glucose tolerance in mice. We provided C57BL/6 mice with a control (chow and water) or experimental (chow, water and sugar solution) diet across two consecutive 28-day exposure periods, and monitored changes in body composition, glucose tolerance, cephalic-phase insulin release (CPIR) and insulin sensitivity. The sugar solutions contained 11% concentrations of Gluc or HiFruc syrup; these syrups were derived from either corn starch or cellulose. In Experiment 1, consumption of the Gluc diets reliably enhanced glucose tolerance, while consumption of the HiFruc diets did not. Mice on the Gluc diets exhibited higher CPIR (relative to baseline) by the end of exposure period 1, whereas mice on the control and HiFruc diets did not do so until the end of exposure period 2. Mice on the Gluc diets also exhibited higher insulin sensitivity than control mice at the end of exposure period 2, while mice on the HiFruc diets did not. In Experiment 2, we repeated the previous experiment, but limited testing to the corn-based Gluc and HiFruc syrups. We found, once again, that consumption of the Gluc (but not the HiFruc) diet enhanced glucose tolerance, in part by increasing CPIR and insulin sensitivity. These results show that mice can adapt metabolically to high glucose diets, and that this adaptation process involves upregulating at least two components of the insulin response system.

Fructose metabolism and its role in pig production: A mini-review

Epidemiological studies have shown that excessive intake of fructose is largely responsible for the increasing incidence of non-alcoholic fatty liver, obesity, and diabetes. However, depending on the amount of fructose consumption from diet, the metabolic role of fructose is controversial. Recently, there have been increasing studies reporting that diets low in fructose expand the surface area of the gut and increase nutrient absorption in mouse model, which is widely used in fructose-related studies. However, excessive fructose consumption spills over from the small intestine into the liver for steatosis and increases the risk of colon cancer. Therefore, suitable animal models may be needed to study fructose-induced metabolic changes. Along with its use in global meat production, pig is well-known as a biomedical model with an advantage over murine and other animal models as it has similar nutrition and metabolism to human in anatomical and physiological aspects. Here, we review the characteristics and metabolism of fructose and summarize observations of fructose in pig reproduction, growth, and development as well as acting as a human biomedical model. This review highlights fructose metabolism from the intestine to the blood cycle and presents the critical role of fructose in pig, which could provide new strategies for curbing human metabolic diseases and promoting pig production.

Metabolic Syndrome: Lessons from Rodent and Drosophila Models

Overweight and obesity are health conditions tightly related to a number of metabolic complications collectively called “metabolic syndrome” (MetS). Clinical diagnosis of MetS includes the presence of the increased waist circumference or so-called abdominal obesity, reduced high density lipoprotein level, elevated blood pressure, and increased blood glucose and triacylglyceride levels. Different approaches, including diet-induced and genetically induced animal models, have been developed to study MetS pathogenesis and underlying mechanisms. Studies of metabolic disturbances in the fruit fly Drosophila and mammalian models along with humans have demonstrated that fruit flies and small mammalian models like rats and mice have many similarities with humans in basic metabolic functions and share many molecular mechanisms which regulate these metabolic processes. In this paper, we describe diet-induced, chemically and genetically induced animal models of the MetS. The advantages and limitations of rodent and Drosophila models of MetS and obesity are also analyzed.

Fructose-mediated NLRP3 activation induces inflammation and lipogenesis in adipose tissue

Adipose tissue plays a crucial role in energy intake and regulation of metabolic homeostasis. Fructose consumption implicates in development and progression of metabolic dysfunctions. Fructose is a lipogenic sugar known to induce inflammatory response. However, the role of specific inflammatory signal such as nucleotide-binding and oligomerization domain-like receptor, leucine-rich repeat and pyrin domain containing protein 3 (NLRP3) in fructose-induced inflammatory response and its relevance to lipogenesis in adipose tissue are elusive. We assessed NLRP3 activation and its significance in inflammatory response and lipogenesis in epididymal adipose tissue of 60% fructose diet (HFrD)-fed rats. The long term consumption of HFrD led to impairment of glucose metabolism, development of visceral adiposity, insulin resistance, and elevation of serum triglycerides level, accompanied by activation of NLRP3 in adipose tissue. NLRP3 inflammasome activation in adipose tissue was associated with up-regulated expression of Nlrp3, Asc, and Caspase-1, and raised caspase-1 activity, which resulted in increased expression of IL-1β and IL-18 and secretion of IL-1β. Moreover, lipid accumulation and expression of transcription factors exacerbating accumulation of lipids were augmented in adipose tissue of HFrD-fed rats. Treatment with glyburide, quercetin or allopurinol corrected HFrD-induced dyslipidemia or hyperuricemia, and blocked NLRP3 activation, leading to mitigated inflammatory signalling and lipid accumulation in adipose tissue, improved glucose tolerance and insulin sensitivity in HFrD-fed rats. These data suggest the role of NLRP3 inflammasome to establish linkage among inflammation, lipid accumulation and insulin resistance in adipose tissue, and targeting NLRP3 inflammasome may be a plausible approach for prevention and management for fructose-induced metabolic impairments.

Impact of High Aspartame and High Fructose Diet on Vascular Reactivity, Glucose Metabolism and Liver Structure in Diabetic Rats

BACKGROUND: Diabetes mellitus is a chronic metabolic disorder, affected by fructose, and artificial sweeteners. Aspartame and fructose are popularly used, by diabetics, as substitutes to glucose. AIM: This study evaluated the effect of high aspartame and fructose on vascular reactivity, glucose, and hepatic metabolism in diabetic rats. MATERIALS AND METHODS: Forty-eight male rats were divided into six groups: Control, control-diabetic, aspartame, aspartame-diabetic, fructose, and fructose-diabetic. After 60 days, blood pressure, vascular reactivity to norepinephrine, Lipid profile, fasting glucose, insulin, homeostasis model assessment of insulin resistance (HOMA-IR), leptin, and Malondialdehyde (MDA) were measured. RESULTS: High aspartame alone or with diabetes, decreased leptin, vascular reactivity, and increased triglyceride, cholesterol, MDA, and fasting blood glucose. Hepatic tissues showed dilated congested vessels, cellular infiltration, decreased Periodic Acid Schiff’s reaction, and increased collagenous fibers. High fructose decreased leptin, high-density lipoprotein, vascular reactivity, and increased cholesterol, Low-density lipoprotein, MDA, glucose, and HOMA-IR. Hepatic tissues showed more fatty infiltration, glycogen deposition, and increased collagenous-fibers. The condition became worse in diabetes-treated rats. CONCLUSION: High aspartame and high fructose diet caused deleterious effects on diabetic rats by atherogenic, oxidative stress, vascular, glucose, and hepatic tissue metabolism impairment.

It's What and When You Eat: An Overview of Transcriptional and Epigenetic Responses to Dietary Perturbations in Pancreatic Islets

Our ever-changing modern environment is a significant contributor to the increased prevalence of many chronic diseases, and particularly, type 2 diabetes mellitus (T2DM). Although the modern era has ushered in numerous changes to our daily living conditions, changes in "what" and "when" we eat appear to disproportionately fuel the rise of T2DM. The pancreatic islet is a key biological controller of an organism's glucose homeostasis and thus plays an outsized role to coordinate the response to environmental factors to preserve euglycemia through a delicate balance of endocrine outputs. Both successful and failed adaptation to dynamic environmental stimuli has been postulated to occur due to changes in the transcriptional and epigenetic regulation of pathways associated with islet secretory function and survival. Therefore, in this review we examined and evaluated the current evidence elucidating the key epigenetic mechanisms and transcriptional programs underlying the islet's coordinated response to the interaction between the timing and the composition of dietary nutrients common to modern lifestyles. With the explosion of next generation sequencing, along with the development of novel informatic and -omic approaches, future work will continue to unravel the environmental-epigenetic relationship in islet biology with the goal of identifying transcriptional and epigenetic targets associated with islet perturbations in T2DM.

Hypertriglyceridemia Acute Pancreatitis: Animal Experiment Research

In recent years, the number of acute pancreatitis cases caused by hypertriglyceridemia has increased gradually, which has caught the attention of the medical community. However, because the exact mechanism of hypertriglyceridemic acute pancreatitis (HTG-AP) is not clear, treatment and prevention in clinical practice face enormous challenges. Animal models are useful for elucidating the pathogenesis of diseases and developing and testing novel interventions. Therefore, animal experiments have become the key research means for us to understand and treat this disease. We searched almost all HTG-AP animal models by collecting many studies and finally collated common animals such as rats, mice and included some rare animals that are not commonly used, summarizing the methods to model spontaneous pancreatitis and induce pancreatitis. We sorted them on the basis of three aspects, including the selection of different animals, analyzed the characteristics of different animals, different approaches to establish hypertriglyceridemic pancreatitis and their relative advantages and disadvantages, and introduced the applications of these models in studies of pathogenesis and drug therapy. We hope this review can provide relevant comparisons and analyses for researchers who intend to carry out animal experiments and will help researchers to select and establish more suitable animal experimental models according to their own experimental design.

Obesity Risk-Factor Variation Based on Island Clusters: A Secondary Analysis of Indonesian Basic Health Research 2018

Obesity has become a rising global health problem affecting quality of life for adults. The objective of this study is to describe the prevalence of obesity in Indonesian adults based on the cluster of islands. The study also aims to identify the risk factors of obesity in each island cluster. This study analyzes the secondary data of Indonesian Basic Health Research 2018. Data for this analysis comprised 618,910 adults (≥18 years) randomly selected, proportionate to the population size throughout Indonesia. We included 20 variables for the socio-demographic and obesity-related risk factors for analysis. The obesity status was defined using Body Mass Index (BMI) ≥ 25 kg/m². Our current study defines 7 major island clusters as the unit analysis consisting of 34 provinces in Indonesia. Descriptive analysis was conducted to determine the characteristics of the population and to calculate the prevalence of obesity within the provinces in each of the island clusters. Multivariate logistic regression analyses to calculate the odds ratios (ORs) was performed using SPSS version 27. The study results show that all the island clusters have at least one province with an obesity prevalence above the national prevalence (35.4%). Six out of twenty variables, comprising four dietary factors (the consumption of sweet food, high-salt food, meat, and carbonated drinks) and one psychological factor (mental health disorders), varied across the island clusters. In conclusion, there was a variation of obesity prevalence of the provinces within and between island clusters. The variation of risk factors found in each island cluster suggests that a government rethink of the current intervention strategies to address obesity is recommended.

Adolescent high-fructose corn syrup consumption leads to dysfunction in adult affective behaviors and mesolimbic proteins in male Sprague-Dawley rats

Adolescence is a critical period of development, during which the brain undergoes rapid maturation. Problematically, adolescents are the top consumers of high fructose corn syrup (HFCS) sweetened beverages and snacks, which may have neurodevelopmental consequences. While HFCS consumption has been linked to an increased likelihood of obesity and other physical health impairments, the link between HFCS and persistent behavioral changes is not yet fully established. The present study aimed to assess whether adolescent HFCS consumption could lead to alterations in adult behaviors and protein expression, following cessation. Adolescent HFCS-exposure contributed to deficits in learning and motivation on an effort-related T-Maze procedure, as well as increased immobility time in the forced swim paradigm during adulthood. Molecularly, protracted decreases in accumbal dopamine D1 and D2 receptors and protein kinase G (PKG), as well as increases in tyrosine hydroxylase and GluA2 receptor subunits, were observed following HFCS-exposure. Taken together, these data suggest that adolescent HFCS-consumption leads to protracted dysfunction in affective behaviors and alterations in accumbal proteins which persist following cessation of HFCS-consumption.

Dietary fructose and its association with the metabolic syndrome in Lebanese healthy adults: a cross-sectional study

BACKGROUND

Epidemiological studies investigating the association between dietary fructose intake and the metabolic syndrome (MetS) are scarce and have produced controversial findings. This study aimed at (1) assessing total dietary fructose intake in a sample of Lebanese healthy adults, and determining the intake levels of natural vs. added fructose; (2) investigating the association of dietary fructose with MetS; and (3) identifying the socioeconomic and lifestyle factors associated with high fructose intake.

METHODS

A cross-sectional survey was conducted on a representative sample of adults living in Beirut, Lebanon (n = 283). Anthropometric and biochemical data were collected, and dietary intake was assessed using a food frequency questionnaire. Intakes of naturally-occurring fructose from fructose-containing food sources, such as fruits, vegetables, honey, were considered as "natural fructose". Acknowledging that the most common form of added sugar in commodities is sucrose or High Fructose Corn Syrup (HFCS), 50% of added sugar in food products was considered as added fructose. Total dietary fructose intake was calculated by summing up natural and added fructose intakes. Logistic regression analyses were conducted to investigate the association of total, added and natural fructose intakes with the MetS and to identify the socioeconomic predictors of high fructose intake.

RESULTS

Mean intake of total fructose was estimated at 51.42 ± 35.54 g/day, representing 6.58 ± 3.71% of energy intakes (EI). Natural and added fructose intakes were estimated at 12.29 ± 8.57 and 39.12 ± 34.10 g/day (1.78 ± 1.41% EI and 4.80 ± 3.56% EI), respectively. Participants in the highest quartile of total and added fructose intakes had higher odds of MetS (OR = 2.84, 95%CI: 1.01, 7.94 and OR = 3.18, 95%CI: 1.06, 9.49, respectively). In contrast, natural fructose intake was not associated with MetS. Age, gender and crowding index were identified as factors that may modulate dietary fructose intakes.

CONCLUSIONS

The observed association between high added fructose intake and the MetS highlights the need for public health strategies aimed at limiting sugar intake from industrialized foods and promoting healthier dietary patterns in Lebanon.

Interaction of dietary carbohydrate and fat on glucose metabolism in growing pigs

Increased consumption of fructose has been suggested to be a contributing cause of the increased rates of obesity in humans. Rodent studies have shown an increase in de novo lipogenesis and decreased insulin sensitivity in response to feeding high levels of fructose, but it is unclear if these effects occur in the same progression in humans. We aimed to develop a swine model for studying changes in glucose metabolism and insulin resistance resulting from dietary carbohydrate alone or in combination with high dietary fat. Two experiments were conducted to determine if the source of dietary carbohydrate, with or without added fat, had an effect on body weight gain, glucose metabolism, or insulin response in growing pigs. In the first experiment, pigs (24 barrows, initial body weight 28 kg) were fed one of 4 diets in which the source of carbohydrate was varied: 1) 20% starch; 2) 10% glucose + 10% starch; 3) 10% fructose + 10% starch; and 4) 20% fructose for 9 weeks. There were no differences in growth rate or glucose clearance observed. Experiment 2 was conducted as a 3 × 2 factorial with the main effects of carbohydrate source (20% starch, glucose, or fructose) and added fat level (0 vs 10%). Pigs (24 barrows, initial body weight 71 kg) were fed one of 6 experimental diets for 9 weeks. Compared to the other dietary treatments, pigs fed fructose with high fat had an elevated glucose area under the curve during the GTT (Carbohydrate x Fat interaction, P < 0.01). This same group had a lower insulin response (Carbohydrate x Fat, P < 0.05). This work demonstrates that pigs can be a viable model to assess the long-term effects of dietary carbohydrates on metabolism and body composition. Studies of longer duration are needed to determine if these changes are indicative of insulin resistance.

Glucose but Not Fructose Alters the Intestinal Paracellular Permeability in Association With Gut Inflammation and Dysbiosis in Mice

A causal correlation between the metabolic disorders associated with sugar intake and disruption of the gastrointestinal (GI) homeostasis has been suggested, but the underlying mechanisms remain unclear. To unravel these mechanisms, we investigated the effect of physiological amounts of fructose and glucose on barrier functions and inflammatory status in various regions of the GI tract and on the cecal microbiota composition. C57BL/6 mice were fed chow diet and given 15% glucose or 15% fructose in drinking water for 9 weeks. We monitored caloric intake, body weight, glucose intolerance, and adiposity. The intestinal paracellular permeability, cytokine, and tight junction protein expression were assessed in the jejunum, cecum, and colon. In the cecum, the microbiota composition was determined. Glucose-fed mice developed a marked increase in total adiposity, glucose intolerance, and paracellular permeability in the jejunum and cecum while fructose absorption did not affect any of these parameters. Fructose-fed mice displayed increased circulation levels of IL6. In the cecum, both glucose and fructose intake were associated with an increase in Il13, Ifnγ, and Tnfα mRNA and MLCK protein levels. To clarify the relationships between monosaccharides and barrier function, we measured the permeability of Caco-2 cell monolayers in response to IFNγ+TNFα in the presence of glucose or fructose. In vitro, IFNγ+TNFα-induced intestinal permeability increase was less pronounced in response to fructose than glucose. Mice treated with glucose showed an enrichment of Lachnospiracae and Desulfovibrionaceae while the fructose increased relative abundance of Lactobacillaceae. Correlations between pro-inflammatory cytokine gene expression and bacterial abundance highlighted the potential role of members of Desulfovibrio and Lachnospiraceae NK4A136 group genera in the inflammation observed in response to glucose intake. The increase in intestinal inflammation and circulating levels of IL6 in response to fructose was observed in the absence of intestinal permeability modification, suggesting that the intestinal permeability alteration does not precede the onset of metabolic outcome (low-grade inflammation, hyperglycemia) associated with chronic fructose consumption. The data also highlight the deleterious effects of glucose on gut barrier function along the GI tract and suggest that Desulfovibrionaceae and Lachnospiraceae play a key role in the onset of GI inflammation in response to glucose.

Low Dietary n6/n3 Ratio Attenuates Changes in the NRF 2 Gene Expression, Lipid Peroxidation, and Inflammatory Markers Induced by Fructose Overconsumption in the Rat Abdominal Adipose Tissue

The objective of this study was to examine the benefits of different n6/n3 polyunsaturated fatty acid ratios on the lipid metabolism, insulin resistance, and oxidative stress in the adipose tissue of rats fed a high-fructose diet. Male and female rats were divided into four groups: a control group (CON) (n6/n3 ratio ~7), a high-fructose group (HF) (n6/n3 ratio ~7), an N6-HF group (n6/n3 ratio ~50), and the DHA-HF group (n6/n3 ratio ~1, with the addition of docosahexaenoic (DHA) and eicosapentaenoic (EPA) acid). The CON group received plain water and the HF group received 15% fructose in their drinking water. Fructose induced an increase in the content of serum triglycerides, serum cholesterol, and HOMA-IR index. Among the fatty acids, elevated proportions of C18:1n9 and C16:1n7, as well as an increase in total monounsaturated fatty acid (MUFA), were found in the adipose tissue of the HF group. Fructose treatment also changed oxidative parameters, including a marked increase in the serum malondialdehyde (MDA) content. Meanwhile, DHA supplementation caused a significant decrease in the serum MDA concentration in comparison with the HF group. In addition, DHA/EPA supplementation attenuated oxidative stress by increasing NRF 2 gene expression. Fructose treatment also significantly decreased the adiponectin level, while DHA supplementation ameliorated it. The changes observed in this trial, including the decrease in the content of DHA and EPA, the decreased EPA/ARA ratio, and the increase in the expression of inflammatory genes, are characteristics of the low-grade inflammation caused by fructose treatment. These changes in the rat adipose tissue could be prevented by dietary intervention consisting of DHA supplementation and a low n6/n3 ratio.

Temporal effect of fructose supplementation at different concentrations on hepatic metabolism of Wistar rats

INTRODUCTION

Introduction: in the last few years important changes have occurred in nutritional patterns. There has been an increase in the consumption of simple carbohydrates such as fructose, which has been associated with numerous metabolic disorders, including hepatic steatosis. Materials and methods: we sought to evaluate the impact of fructose consumption, as diluted in water at different concentrations, for two time periods, on the metabolic parameters of Wistar rats using ANOVA. Results: our data indicate that both time and fructose concentration promote variations in animal body mass, and in food, water, and caloric intake. The time variable influenced the modulation of biochemical parameters such as serum concentrations of glucose and total cholesterol. Both fructose concentration and time of exposure influenced the concentrations of serum triglycerides, creatinine, AST, TNF, and IL-6. When evaluating redox status and oxidative damage markers, we observed that fructose concentration and exposure time had an effect on total glutathione levels, which decreased with an increase in concentration and time. For superoxide dismutase, we evaluated the effects of time and interaction. A significant interaction was observed for TBARS. For carbonylated proteins, exposure time was a fundamental factor in generating an effect. Conclusions: we demonstrated that fructose modulates the parameters of triglycerides and total liver cholesterol, and that time influences the number of hepatocytes. Our data suggest that fructose concentration, exposure time, and an interaction between these two parameters have a significant effect on the metabolic parameters responsible for the development of non-alcoholic fatty liver disease.

Danggui-Shaoyao-San Improves Gut Microbia Dysbiosis and Hepatic Lipid Homeostasis in Fructose-Fed Rats

Metabolic syndrome (MetS) is a pathological state of many abnormal metabolic sections. These abnormalities are closely related to diabetes, heart pathologies and other vascular diseases. Danggui-Shaoyao-San (DSS) is a traditional Chinese medicine formula that has been used as a therapy for Alzheimer’s disease. DSS has rarely been reported in the application of MetS and its mechanism of how it improves gut microbia dysbiosis and hepatic lipid homeostasis. In this study, three extracts of DSS were obtained using water, 50% methanol in water and methanol as extracting solvents. Their chemical substances were analyzed by ultra-performance liquid chromatography coupled with quadrupole time-of-flight mass (UPLC-Q/TOF-MS). Pharmacodynamic effect of the extracts were evaluated by comparison of biochemical factors, 16S rRNA sequencing test for gut microbiota analysis, as well as metabonomic and transcriptomic assessments on liver tissues from fructose-fed rats. This study aimed at investigating DSS’s mechanism of regulating blood lipid, anti-inflammation and reducing blood glucose. The results showed that the 50% methanol extract (HME) was more effective. It was worth noting that hydroxysteroid 17β-dehydrogenase 13 (HSD17β13) as a critical element of increasing blood lipid biomarker-triglyceride (TG), was decreased markedly by DSS. The influence from upgraded hydroxysteroid 17β-dehydrogenase 7 (HSD17β7) may be stronger than that from downgraded Lactobacillus in the aspect of regulating back blood lipid biomarker-total cholesterol (TC). The differential down-regulation of tumornecrosis factor alpha (TNF-α) and the significant up-regulation of Akkermansia showed the effective effect of anti-inflammation by DSS. The declining glycine and alanine induced the lowering glucose and lactate. It demonstrated that DSS slowed down the reaction of gluconeogenesis to reduce the blood glucose. The results demonstrated that DSS improved pathological symptoms of MetS and some special biochemical factors in three aspects by better regulating intestinal floras and improving hepatic gene expressions and metabolites.

The association between Sugars Sweetened Beverages (SSBs) and lipid profile among children and youth: A systematic review and dose-response meta-analysis of cross-sectional studies

BACKGROUND

The relationship between sugar-sweetened beverages (SSBs) intake and serum lipids among children and youth has been reported in several studies, but the results are still controversial.

OBJECTIVE

In the current study, we summarized the results of studies that assessed the relationship between SSBs consumption and serum lipids among children and youth in a systematic review and dose-response meta-analysis.

METHODS

The PubMed, Web of Sciences, Cochrane and Scopus electronic databases were searched for observational studies reporting an association between SSBs intake and serum lipids among children and youth that were published before May 2020. For data extracted from cohort studies, only cross-sectional baseline data were included in the current meta-analysis. The Random effects model was used to estimate the pooled weighted mean difference (WMD) and 95% confidence intervals (CI). Heterogeneity was assessed with the Cochran Q test and I² statistics.

RESULTS

In our search, 1845 studies were retrieved of which 13 studies (two cohorts and eleven cross-sectional) were included. High SSB consumption was associated with 1.21 mg/dL increase in low-density lipoprotein cholesterol (LDL-C; pooled WMD: 1.21 mg/dL; 95% CI: 0.23, 2.20; P = .01), 1.45 mg/dL decrease in high-density lipoprotein cholesterol (HDL-C, pooled WMD: -1.46 mg/dL; 95% CI, -2.25, -0.67; P < .0001) and 2.49 mg/dL decrease in total cholesterol (TC, pooled WMD: -2.49 mg/dL; 95% CI, -2.89, -2.10; P < .0001). In dose-response meta-analysis, there was an evidence of departure from linearity in the relationship between SSB consumption and change in LDL-C (P-_nonlinearity  = .03) and TC (P-_nonlinearity  = .01). However, no departure from linearity was observed between SSB intake and change in HDL-C (P-_nonlinearity  = .56) or triglyceride (TG) values (P-_nonlinearity  = .85).

CONCLUSION

According to our results, high SSB consumption was significantly associated with higher LDL-C and lower HDL-C and TC among children and youth. However, owing to the limited number of the included studies, further well-designed interventional studies are needed to better elucidate causality.

Neural mechanisms underlying the role of fructose in overfeeding

Fructose consumption has been linked with metabolic syndrome and obesity. Fructose-based sweeteners like high fructose corn syrup taste sweeter, improve food palatability, and are increasingly prevalent in our diet. The increase in fructose consumption precedes the rise in obesity and is a contributing driver to the obesity epidemic worldwide. The role of dietary fructose in obesity can be multifactorial by promoting visceral adiposity, hypertension, and insulin resistance. Interestingly, one emergent finding from human and animal studies is that dietary fructose promotes overfeeding. As the brain is a critical regulator of food intake, we reviewed the evidence that fructose can act in the brain and elucidated the major brain systems underlying fructose-induced overfeeding. We found that fructose acts on multiple interdependent brain systems to increase orexigenic drive and the incentive salience of food while decreasing the latency between food bouts and reducing cognitive control to disinhibit feeding. We concluded that the collective actions of fructose may promote feeding behavior by producing a hunger-like state in the brain.

The high-fructose intake of dams during pregnancy and lactation exerts sex-specific effects on adult rat offspring metabolism

Experimental studies have demonstrated the effects of maternal fructose consumption during pregnancy and lactation on metabolic alterations in their offspring, especially male offspring. However, few studies have focused on female offspring after providing fructose in food to dam rats. Here, we studied whether offspring of both sexes were differentially affected by a maternal high-fructose diet (HFD). For this purpose, Sprague-Dawley rats were fed during pregnancy and lactation with a standard diet (SD) or a HFD (50% w/w). After weaning, offspring were fed an SD; 3 days later, dams were sacrificed, and their offspring were sacrificed on postnatal day 90. Body weight (BW), food and water intake (only for dams), and various biomarkers of metabolic syndrome were measured. When compared to the SD-fed dams, HFD-fed dams had a reduction in BW and food and water intake. Conversely, adiposity, liver weight, liver lipids, and plasma levels of glucose, insulin, cholesterol, triglycerides, and uric acid were increased in HFD-fed dams. Moreover, the BW, food consumption, weight of retroperitoneal fat pads, and liver lipids increased in female and male offspring of HFD-fed dams. Interestingly, the pups of HFD-fed mothers showed increased levels of leptin and insulin resistance and decreased levels of adiponectin which were more pronounced in male offspring than in female offspring. In contrast, a higher increase in BW was shown earlier in female offspring. Thus, high-fructose consumption by dams during pregnancy and lactation led to sex-specific developmental programming of the metabolic syndrome phenotype in adult offspring.

The association between Healthy Beverage Index and anthropometric measures among children: a cross-sectional study

PURPOSE

Several studies evaluated the associations between specific beverages and cardio-metabolic risks among children. However, the evidence on the association between patterns of the beverage consumption and children's anthropometric indices is rare. Therefore, this study was conducted to examine the association between Healthy Beverage Index (HBI) and anthropometric measures among 6-year-old girl children.

METHODS

In this cross-sectional study, 788 children selected from health centers in Tehran, Iran. Data on beverage intake, socio-demographic, physical activity, and anthropometric characteristics were evaluated using reliable and validated standard protocols. The predefined HBI was calculated based on the previous research.

RESULTS

After controlling for several confounders [mother age, mother body mass index, mother physical activity, socioeconomic status, children physical activity and energy intake, total oils (all kinds of oils like animal and plant oils), and total sweet foods (sweet foods except sweetened beverages)], being in the third compared to the first tertile of HBI among children was associated with increased odds of wasting (OR: 5.16; 95% CI 1.5-17.79) and underweight/wasting (OR: 1.81; 95% CI 1.07-3.07). Among the HBI components, just being in the third compared to the first tertile of high-fat milk was inversely associated with decreased odds of wasting (OR: 0.18; 95% CI 0.04-0.73).

CONCLUSIONS

The HBI among children was associated with higher odds of wasting and underweight/wasting. In addition, high-fat milk consumption decreased the odds of wasting among children. Further prospective studies need to confirm these results.

LEVEL OF EVIDENCE

Level V, descriptive cross-sectional study.

High Fructose Corn Syrup-Moderate Fat Diet Potentiates Anxio-Depressive Behavior and Alters Ventral Striatal Neuronal Signaling

The neurobiological mechanisms that mediate psychiatric comorbidities associated with metabolic disorders such as obesity, metabolic syndrome and diabetes remain obscure. High fructose corn syrup (HFCS) is widely used in beverages and is often included in food products with moderate or high fat content that have been linked to many serious health issues including diabetes and obesity. However, the impact of such foods on the brain has not been fully characterized. Here, we evaluated the effects of long-term consumption of a HFCS-Moderate Fat diet (HFCS-MFD) on behavior, neuronal signal transduction, gut microbiota, and serum metabolomic profile in mice to better understand how its consumption and resulting obesity and metabolic alterations relate to behavioral dysfunction. Mice fed HFCS-MFD for 16 weeks displayed enhanced anxiogenesis, increased behavioral despair, and impaired social interactions. Furthermore, the HFCS-MFD induced gut microbiota dysbiosis and lowered serum levels of serotonin and its tryptophan-based precursors. Importantly, the HFCS-MFD altered neuronal signaling in the ventral striatum including reduced inhibitory phosphorylation of glycogen synthase kinase 3β (GSK3β), increased expression of ΔFosB, increased Cdk5-dependent phosphorylation of DARPP-32, and reduced PKA-dependent phosphorylation of the GluR1 subunit of the AMPA receptor. These findings suggest that HFCS-MFD-induced changes in the gut microbiota and neuroactive metabolites may contribute to maladaptive alterations in ventral striatal function that underlie neurobehavioral impairment. While future studies are essential to further evaluate the interplay between these factors in obesity and metabolic syndrome-associated behavioral comorbidities, these data underscore the important role of peripheral-CNS interactions in diet-induced behavioral and brain function. This study also highlights the clinical need to address neurobehavioral comorbidities associated with obesity and metabolic syndrome.

Fructose Consumption-Free Sugars and Their Health Effects

BACKGROUND

The excessive consumption of free sugars, including fructose, is considered a cause of overweight and metabolic syndrome throughout the Western world. In Germany, the prevalence of overweight and obesity among adults (54%, 18%) and children (15%, 6%) has risen in the past few decades and has now become stable at a high level. The causative role of fructose is unclear.

METHODS

This review is based on publications retrieved by a selective search in PubMed and the Cochrane Library, with special attention to international guidelines and expert recommendations.

RESULTS

The hepatic metabolism of fructose is insulin-independent; because of the lack of a feedback mechanism, it leads to substrate accumulation, with de novo lipogenesis and gluconeogenesis. Recent meta-analyses with observation periods of one to ten weeks have shown that the consumption of fructose in large amounts leads to weight gain (+ 0.5 kg [0.26; 0.79]), elevated triglyceride levels (+ 0.3 mmol/L [0.11; 0.41]), and steatosis hepatis (intrahepatocellular fat content: + 54% [29; 79%]) when it is associated with a positive energy balance (fructose dose + 25-40% of the total caloric requirement). Meta-analyses in the isocaloric setting have not shown any comparable effects. Children, with their preference for sweet foods and drinks, are prone to excessive sugar consumption. Toddlers under age two are especially vulnerable.

CONCLUSION

The effects that have been observed with the consumption of large amounts of fructose cannot be reliably distinguished from the effects of a generally excessive caloric intake. Further randomized and controlled intervention trials of high quality are needed in order to determine the metabolic effects of fructose consumed under isocaloric conditions. To lessen individual consumption of sugar, sugary dietary items such as sweetened soft drinks, fruit juice, and smoothies should be avoided in favor of water as a beverage and fresh fruit.

Macronutrient Determinants of Obesity, Insulin Resistance and Metabolic Health

Obesity caused by the overconsumption of calories has increased to epidemic proportions. Insulin resistance is often associated with an increased adiposity and is a precipitating factor in the development of cardiovascular disease, type 2 diabetes, and altered metabolic health. Of the various factors contributing to metabolic impairments, nutrition is the major modifiable factor that can be targeted to counter the rising prevalence of obesity and metabolic diseases. However, the macronutrient composition of a nutritionally balanced "healthy diet" are unclear, and so far, no tested dietary intervention has been successful in achieving long-term compliance and reductions in body weight and associated beneficial health outcomes. In the current review, we briefly describe the role of the three major macronutrients, carbohydrates, fats, and proteins, and their role in metabolic health, and provide mechanistic insights. We also discuss how an integrated multi-dimensional approach to nutritional science could help in reconciling apparently conflicting findings.

Hepatoprotective effect of silymarin on fructose induced nonalcoholic fatty liver disease in male albino wistar rats

BACKGROUND

Nonalcoholic fatty liver disease (NAFLD) is one of the most common causes of chronic liver disease in the Western world, and it's likely to parallel the increasing prevalence of type 2 diabetes, obesity, and other components of metabolic syndrome. However, optimal treatment for NAFLD has not been established yet. Therefore, this study investigated the hepatoprotective effect of silymarin on fructose-induced nonalcoholic fatty liver disease in rats.

METHODS

Thirty male Wistar rats were randomly divided into five groups; normal control group that consumed tap water, silymarin control group that consumed tap water and silymarin (400 mg/kg/day), fructose control group that consumed 20% fructose solution, treatment group that consumed 20% fructose solution and silymarin (200 mg/kg/day), and another treatment group that consumed 20% fructose solution and silymarin (400 mg/kg/day). Hepatic triglyceride, serum lipid profile, lipid peroxidation, antioxidant level, morphological features, and histopathological changes were investigated. The data were analyzed using one-way analysis of variance (ANOVA) followed by Tukey multiple comparison test. Statistical significance was determined at p < 0.05.

RESULTS

This study showed that the fructose control group had a significantly high value in the stage of steatosis grade, hepatic triglyceride, serum triglyceride, total cholesterol, low-density lipoprotein cholesterol, alanine aminotransferase, aspartate aminotransferase, and hepatic malondialdehyde concentration as compared to the normal control. However, significantly low values of reduced glutathione and plasma total antioxidant capacity were found. The altered parameters due to fructose drastic effect were ameliorated by silymarin treatment.

CONCLUSIONS

The fructose control group developed dyslipidemia, oxidative stress, and mild steatosis that are the characteristics features of NAFLD. However, silymarin-treated groups showed amelioration in oxidative stress, dyslipidemia, and steatosis.

Ipomoea hederacea Jacq.: A plant with promising antihypertensive and cardio-protective effects

ETHNOPHARMACOLOGICAL RELEVANCE

Seeds of Ipomoea hederacea Jacq. (family: Convolvulaceae) are traditionally used to treat high blood pressure and cardiac diseases.

AIM OF THE STUDY

Present study was conducted to validate the traditional claim and explore the possible mechanism(s) of antihypertensive effects of I. hederacea.

MATERIALS AND METHODS

Aqueous-ethanolic extract and activity based fractions of I. hederacea were evaluated using invasive blood pressure measuring technique, isolated tissue experiments, fructose induced hypertension/metabolic syndrome and biochemical analysis.Phytochemical analysis of active fraction was performed with aim to identify chemical composition of I. hederacea seeds. LC-MS analysis was also performed to identify the compounds proposed to be present in active fraction of I. hederacea seeds.

RESULTS

Crude extract/fractions of I. hederacea showed dose (0.01-100 mg/kg) dependent significant hypotensive effect in normotensive anesthetized rats, similar to verapamil (0.01-30 mg/kg). Pretreatment with hexamethonium and atropine mediated no significant changes in hypotensive effect of butanol fraction of I. hederacea (Ih.Bn) at 3 mg/kg dose. However, a significant decrease in the hypotensive effect of Ih.Bn 3 mg/kg (-34.82 ± 3.36%; p < 0.05) was observed in the presence of L-NAME (20 mg/kg). Similarly, Ih.Bn (3 mg/kg) showed no significant effect on angiotensin-II response. However, response of phenylephrine (45.60 ± 9.63%; p < 0.05) and dobutamine (18.25 ± 2.10%; p < 0.01) was significantly decreased in the presence of Ih.Bn 3 mg/kg. Ih.Bn also exhibited dose dependent (0.01-100 mg/kg) antihypertensive effect in fructose induced hypertensive rats, similar to verapamil (0.01-30 mg/kg). Concomitant treatment with Ih.Bn (3, 10 and 30 mg/kg) for six weeks showed a dose dependent profound protection with significant (p < 0.01) effect at 30 mg/kg against fructose induced basal mean arterial pressure (142.2 ± 4.62 mmHg). Ih.Bn did not significantly change response of PE, Ang-II and Epi was observed in invasive and ex vivo techniques. However, Ih.Bn significantly (p < 0.01; p < 0.001) prevented against decrease in vascular response of acetylcholine in anesthetized rats and in isolated aorta of rat. A significant dose dependent decrease in triglyceride and glucose level (p < 0.001), and increase in HDL level (p < 0.05) was observed in Ih.Bn treated groups. Results of LC-MS analysis of Ih.Bn showed the presence of 24 compounds that belong to different chemical classes, including carboxylic acid, flavonoids, oligopeptides and tripeptide that are known to have antihypertensive and vasorelaxant properties.

CONCLUSIONS

Results of present study indicate the presence of hypotensive/antihypertensive effect in crude extract/fractions of I. hederacea with most potent effect shown by butanol fraction (Ih.Bn), possibly mediated through α₁ blocking, β blocking and iNOS/cGMP stimulating activity.

Fructose and Non-Alcoholic Steatohepatitis

Background: The excessive consumption of free sugars is mainly responsible for the high prevalence of obesity and metabolic syndrome in industrialized countries. More and more studies indicate that fructose is involved in the pathophysiology and also in the degree of disease of non-alcoholic fatty liver disease (NAFLD). In epidemiologic studies, energy-adjusted higher fructose consumption correlates with NAFLD in overweight adults. In addition to glucose, fructose, as an equivalent component of conventional household sugar, appears to have negative metabolic effects in particular due to its exclusive hepatic metabolism. Liver-related mortality is strictly associated with the degree of fibrosis, whereas the most common cause of death in patients suffering from NAFLD and non-alcoholic steatohepatitis (NASH) are still cardiovascular diseases. In this review article, we have summarized the current state of knowledge regarding a relationship between fructose consumption, liver fibrosis and life expectancy in NASH. Method: Selective literature search in PubMed using the keywords 'non-alcoholic fatty liver', 'fructose', and 'fibrosis' was conducted. Results: The rate of overweight and obesity is significantly higher in both, adult and pediatric NASH patients. The consumption of free sugars is currently three times the maximum recommended amount of 10% of the energy intake. The current literature shows weight gain, negative effects on fat and carbohydrate metabolism and NASH with hypercaloric intake of fructose. Conclusions: Excessive fructose consumption is associated with negative health consequences. Whether this is due to an excess of energy or the particular metabolism of fructose remains open with the current study situation. The urgently needed reduction in sugar consumption could be achieved through a combination of binding nutritional policy measures including taxation of sugary soft drinks. Previous studies suggest that diet-related fructose intake exceeding the amount contained in vegetables and fruits lead to an increase of hepatic lipogenesis. Thus, further studies to clarify the protective contribution of low-fructose intake to positively influence NAFLD in industrial population are urgently required.

Exposure to high fructose corn syrup during adolescence in the mouse alters hepatic metabolism and the microbiome in a sex-specific manner

KEY POINTS

The prevalence of obesity and non-alcoholic fatty liver disease in children is dramatically increasing at the same time as consumption of foods with a high sugar content. Intake of high fructose corn syrup (HFCS) is a possible aetiology as it is thought to be more lipogenic than glucose. In a mouse model, HFCS intake during adolescence increased fat mass and hepatic lipid levels in male and female mice. However, only males showed impaired glucose tolerance. Multiple metabolites including lipids, bile acids, carbohydrates and amino acids were altered in liver in a sex-specific manner at 6 weeks of age. Some of these changes were also present in adulthood even though HFCS exposure ended at 6 weeks. HFCS significantly altered the gut microbiome, which was associated with changes in key microbial metabolites. These results suggest that HFCS intake during adolescence has profound metabolic changes that are linked to changes in the microbiome and these changes are sex-specific.

ABSTRACT

The rapid increase in obesity, diabetes and fatty liver disease in children over the past 20 years has been linked to increased consumption of high fructose corn syrup (HFCS), making it essential to determine the short- and long-term effects of HFCS during this vulnerable developmental window. We hypothesized that HFCS exposure during adolescence significantly impairs hepatic metabolic signalling pathways and alters gut microbial composition, contributing to changes in energy metabolism with sex-specific effects. C57bl/6J mice with free access to HFCS during adolescence (3-6 weeks of age) underwent glucose tolerance and body composition testing and hepatic metabolomics, gene expression and triglyceride content analysis at 6 and 30 weeks of age (n = 6-8 per sex). At 6 weeks HFCS-exposed mice had significant increases in fat mass, glucose intolerance, hepatic triglycerides (females) and de novo lipogenesis gene expression (ACC, DGAT, FAS, ChREBP, SCD, SREBP, CPT and PPARα) with sex-specific effects. At 30 weeks, HFCS-exposed mice also had abnormalities in glucose tolerance (males) and fat mass (females). HFCS exposure enriched carbohydrate, amino acid, long chain fatty acid and secondary bile acid metabolism at 6 weeks with changes in secondary bile metabolism at 6 and 30 weeks. Microbiome studies performed immediately before and after HFCS exposure identified profound shifts of microbial species in male mice only. In summary, short-term HFCS exposure during adolescence induces fatty liver, alters important metabolic pathways, some of which continue to be altered in adulthood, and changes the microbiome in a sex-specific manner.

The use of combined high-fructose diet and glyphosate to model rats type 2 diabetes symptomatology

An ideal food-chemical combination that will promote insulin resistance and its consequent development of pancreatic beta-cell dysfunction may open a new vista for Type 2 diabetes (T2D) research. Thus, we investigated the modulatory effects of a high-fructose diet (FRC) combined with glyphosate (GP). Male albino Wistar rats were randomly divided into five groups of eight/group and received distilled water, FRC, GP, and their combinations orally for eight consecutive weeks. We assessed the changes in fasting blood glucose levels (FBGLs), biochemical indices, oxidative stress parameters, and organ histopathology. From the results obtained, FBGLs and serum insulin levels were increased in the FRC-GP (2.3-3.1 and 1.9-2.2 folds) treated rats compared with the control baseline group. Also, the FRC-GP high dose increased FBGLs (1.9 folds), insulin (1.4 folds), triglycerides (1.5 folds), and uric acid (2 folds) levels compared with the FRC group. Malondialdehyde levels increased in the pancreas (54% and 78%) and liver (31.3% and 56.6%) of the FRC-GP treated rats. The FRC-GP treatments reduced serum high-density lipoprotein (57%), total protein (47%), and antioxidant parameters (non-enzymatic and enzymatic, 1.6-1.9 folds) respectively in the treated animals. The weight of the pancreas relative to the body increased (2-3 folds) while we observed mild inflammation and vascular congestion in vital organs in the treated rats. Overall, these results demonstrate the potential of FRC-GP-diet to induce conditions of rats T2D. Also, this novel finding suggests a cost-effective GP as an alternative in this model type and provides further insight into understanding FRC-GP interactions.

N-acetyl cysteine can blunt metabolic and cardiovascular effects via down-regulation of cardiotrophin-1 in rat model of fructose-induced metabolic syndrome

In this study, we investigated the ability of N-acetyl cysteine (NAC) to alleviate the metabolic disorders in fructose-induced metabolic syndrome (MS) in male rats and to examine its protective effect on aortic and cardiac tissues via its influence on cardiotrophin-1 (CT-1) expression. NAC (20 mg/kg b.w./day) was administered to fructose induced MS animals for 12 weeks. Chronic fructose consumption (20% w/v) increased body weight gain, relative heart weight, systolic blood pressure (SBP), diastolic blood pressure (DBP), insulin resistance (IR), and associated with metabolic alterations. Histological and immunohistochemical examination revealed aortic stiffness and myocardial degeneration and fibrosis together with increased CT-1 expression. Treatment with NAC improved IR, SBP, DBP, and mitigated dyslipidaemia and oxidative stress. Additionally, NAC down-regulated CT-1 expression in the heart and aorta. These findings demonstrated the protective effect of NAC against aortic and myocardial degeneration and fibrosis through down-regulation of CT-1 in fructose induced MS animal model.

Direct and Indirect Effect of Honey as a Functional Food Against Metabolic Syndrome and Its Skeletal Complications

Metabolic syndrome (MetS) refers to the simultaneous presence of hypertension, hyperglycemia, dyslipidemia and/or visceral obesity, which predisposes a person to cardiovascular diseases and diabetes. Evidence suggesting the presence of direct and indirect associations between MetS and osteoporosis is growing. Many studies have reported the beneficial effects of polyphenols in alleviating MetS in in vivo and in vitro models through their antioxidant and anti-inflammation actions. This review aims to summarize the effects of honey (based on unifloral and multi-floral nectar sources) on bone metabolism and each component of MetS. A literature search was performed using the PubMed and Scopus databases using specific search strings. Original studies related to components of MetS and bone, and the effects of honey on components of MetS and bone were included. Honey polyphenols could act synergistically in alleviating MetS by preventing oxidative damage and inflammation. Honey intake is shown to reduce blood glucose levels and prevent excessive weight gain. It also improves lipid metabolism by reducing total cholesterol, triglycerides and low-density lipoprotein, as well as increasing high-density lipoprotein. Honey can prevent bone loss by reducing the adverse effects of MetS on bone homeostasis, apart from its direct action on the skeletal system. In conclusion, honey supplementation could be integrated into the management of MetS and MetS-induced bone loss as a preventive and adjunct therapeutic agent.

Diet-induced rodent models of obesity-related metabolic disorders-A guide to a translational perspective

Diet is a critical element determining human health and diseases, and unbalanced food habits are major risk factors for the development of obesity and related metabolic disorders. Despite technological and pharmacological advances, as well as intensification of awareness campaigns, the prevalence of metabolic disorders worldwide is still increasing. Thus, novel therapeutic approaches with increased efficacy are urgently required, which often depends on cellular and molecular investigations using robust animal models. In the absence of perfect rodent models, those induced by excessive consumption of fat and sugars better replicate the key aspects that are the root causes of human metabolic diseases. However, the results obtained using these models cannot be directly compared, particularly because of the use of different dietary protocols, and animal species and strains, among other confounding factors. This review article revisits diet-induced models of obesity and related metabolic disorders, namely, metabolic syndrome, prediabetes, diabetes and nonalcoholic fatty liver disease. A critical analysis focused on the main pathophysiological features of rodent models, as opposed to the criteria defined for humans, is provided as a practical guide with a translational perspective for the establishment of animal models of obesity-related metabolic diseases.

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

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

Effects on weaned male Wistar rats after 104, 197, and 288 days of chronic consumption of nutritive and non-nutritive additives in water

Abstract

It has been suggested that the consumption of artificial sweeteners is related to greater body mass gain and diverse metabolic alterations. In this study, the effect of chronic consumption of nutritive sweeteners (fructose 7% and sucrose 10%) and non-nutritive or low-calorie sweeteners (acesulfame 0.015%, aspartame 0.3%, aspartame:acesulfame mixture 0.04%, saccharin 0.3%, and sucralose 0.19%), in drinking water, as well as a control group with no sweeteners, was evaluated. Body mass gain and glucose, insulin, triglycerides, and total cholesterol levels in blood were the parameters considered. For this purpose, 120 weaned male Wistar rats of the HsdHan:WIST line were used, 15 per group in first stage, then 10 and 5 per group for 2nd and 3rd stages, respectively. Body mass gain, food intake, and beverage consumption were daily quantified. After 104, 197, and 288 days of experimentation the concentrations of glucose, triglycerides, cholesterol, and insulin were determined. Only in the first stage there were significant differences in the body mass gain. In the three stages there were significant differences in the patterns of beverage intake and food consumption. The trend was the same in all 3 stages: rats drank more in the groups of drinks sweetened with nutritive sweeteners and ate more in the groups that drank non-nutritive artificial sweeteners. Regarding the biochemical profile, no sweetener either nutritive or non-nutritive caused that the serum levels of glucose, triglycerides, and cholesterol were at pathological levels. It is concluded that the sweeteners by themselves can modify certain biochemical parameters but not at a pathological level. Furthermore, by themselves they are not capable of triggering excess of body mass or obesity in the early and medium stages of life when consumed together with a balanced diet.

Graphic abstract

The physio-metabolic effects of time-restricting liquid sugar intake to six-hour windows during the mouse active phase: The effects of active phase liquid sugar consumption

Obesity is a major public health concern and overconsumption of unhealthy fats and sugary beverages are contributing factors. Time-restricted feeding can reduce obesity-associated pathophysiological parameters by limiting the time of food consumption; however, the effects of time-restricted sugary water consumption are unknown. To examine whether liquid calorie restriction impacts metabolic health, we measured metabolic parameters in mice provided liquid sugar at various intervals during the active phase. The control (Con) group received tap water, the adlibitum fructose-glucose (ALFG) group received ad libitumsugar water and the early fructose-glucose (EFG) and late fructose-glucose (LFG) groups received liquid sugar during the first and last six hours of the active period, respectively. Each group was given free access to chow. Zeitgeber time (ZT) notation was used to set all experimental time points to lights on as ZT 0. The ALFG group exhibited elevated body and adipose tissue weights compared to the other groups and increased hepatic steatosis compared to the Con group. The ALFG group consumed more calories than the other groups during ZT 6-11, indicating that this window may be critical in the promotion of weight gain from liquid sugar consumption. The EFG group exhibited higher levels of energy expenditure than the Con and LFG groups during the first half of the active period (ZT 12-17); however, there was no difference among the groups during the second half of the active period (ZT18-23). In contrast, the EFG group exhibited lower respiratory exchange ratio than other groups during the inactive period as well as the second half of the active period, indicating that the EFG group had greater metabolic flexibility and utilized lipids when carbohydrates from liquid sugar were not available. Additionally, the EFG group was more insulin tolerant than the ALFG and Con groups. Our results support the hypothesis that time-restricted liquid calorie restriction aids in reducing the detrimental metabolic effects of sugary drink consumption.