Effects of different sweeteners on behavior and neurotransmitters release in mice

Obesogenic potentials of environmental artificial sweeteners with disturbances on both lipid metabolism and neural responses

Artificial sweeteners (ASs) entered the environments after application and emissions. Recent studies showed that some ASs had obesogenic risks. However, it remained unclear whether such risks are common and how they provoke such effects. Presently, the effects of 8 widely used ASs on lipid accumulation were measured in Caenorhabditis elegans. Potential mechanisms were explored with feeding and locomotion behavior, lipid metabolism and neural regulation. Results showed that acesulfame (ACE), aspartame (ASP), saccharin sodium (SOD), sucralose (SUC) and cyclamate (CYC) stimulated lipid accumulation at μg/L levels, showing obesogenic potentials. Behavior investigation showed that ACE, ASP, SOD, SUC and CYC biased more feeding in the energy intake aspect against the locomotion in the energy consumption one. Neotame (NEO), saccharin (SAC) and alitame (ALT) reduced the lipid accumulation without significant obesogenic potentials in the present study. However, all 8 ASs commonly disturbed enzymes (e.g., acetyl-CoA carboxylase) in lipogenesis and those (e.g., carnitine palmitoyl transferase) in lipolysis. In addition, ASs disturbed PPARγ (via expressions of nhr-49), TGF-β/DAF-7 (daf-7) and SREBP (sbp-1) pathways. Moreover, they also interfered neurotransmitters including serotonin (5-HT), dopamine (DA) and acetylcholine (ACh), with influences in Gsα (e.g., via expressions of gsα-1, ser-7), glutamate (e.g., mgl-1), and cGMP-dependent signaling pathways (e.g., egl-4). In summary, environmental ASs commonly disturbed neural regulation connecting behavior and lipid metabolism, and 5 out of 8 showed clear obesogenic potentials. ENVIRONMENTAL IMPLICATION: Artificial sweeteners (ASs) are become emerging pollutants after wide application and continuous emission. Recent studies showed that some environmental ASs had obesogenic risks. The present study employed Caenorhabditis elegans to explore the influences of 8 commonly used ASs on lipid metabolisms and also the underlying mechanisms. Five out of 8 ASs stimulated lipid accumulation at μg/L levels, and they biased energy intake against energy consumption. The other three ASs reduced the lipid accumulation. ASs commonly disturbed lipogenesis and lipolysis via PPARγ, TGF-β and SREBP pathways, and also influenced neurotransmitters with Gsα, glutamate and cGMP-dependent signaling pathways.

Determination of the genotoxic effects of sweeteners, mannitol and lactitol

The changes in dietary habit around the world have led to an increased use of additives in the food. The safety of food additives has been a main focus of research for many years due to the ongoing debate on their potential effects on health. In this study, the in vitro genotoxic effects of mannitol and lactitol, polyols used as sweetener food additives, were evaluated using chromosomal aberrations (CAs) and micronucleus (MN) assays in human peripheral lymphocytes. Additionally, the effects of these sweeteners on the mitotic index (MI) and nuclear division index (NDI) were investigated. Concentrations of 500, 1000, 2000, 4000, and 8000 μg/mL for mannitol and 250, 500, 1000, 2000, and 4000 μg/mL for lactitol were used. The results indicated that both polyols did not affect CA and MN frequency, and did not cause a significant change in NDI at all treatment concentratoins. However, mannitol (except at concentrations of 500 and 1000 μg/mL) and lactitol (except at 250 μg/mL) significantly decreased the MI compared to the control at almost all concentrations and treatment times. In conclusion, it was observed that mannitol and lactitol did not have a significant genotoxic effect at the concentrations used in human lymphocytes in vitro.

Dose of sucrose affects the efficacy of Qiweibaizhu powder on antibiotic-associated diarrhea: Association with intestinal mucosal microbiota, short-chain fatty acids, IL-17, and MUC2

Introduction

Due to the poor taste of Qiweibaizhu powder (QWBZP), patients have difficulty taking medicine, which leads to poor compliance and limits clinical use to a certain extent. In the trend of restricting sugar intake, sweeteners have gained massive popularity, among which sucrose is a commonly used sweetener in preparations. This study aimed to investigate the effect of different sucrose dose addition with antibiotic-associated diarrhea (AAD) by intervened QWBZP on intestinal mucosal microbiota.

Methods

Thirty specific-pathogen-free (SPF) Kunming (KM) male mice were randomly divided into normal group (N), natural recovery group (M), QWBZP group (Q), low dose sucrose group (LQ), medium dose sucrose group (MQ), and high dose sucrose group (HQ). Subsequently, 16S rRNA amplicon sequencing and GC-MS techniques were used to analyze the intestinal mucosal microbiota and short-chain fatty acid (SCFAs) in intestinal contents, respectively, and enzyme-linked immunosorbent assay was used to determine mucin 2 (MUC2) and interleukin 17 (IL-17).

Results

Compared with the Q group, the results showed that with the increase of sucrose dose, the intestinal microbial structure of mice was significantly altered, and the intestinal microbial diversity was elevated, with the poor restoration of the intestinal biological barrier, decreased content of SCFAs, high expression of inflammatory factor IL-17 and decreased content of mucosal protective factor MUC2. In conclusion, we found that the addition of sucrose had an effect on the efficacy of the AAD intervented by QWBZP, which was less effective than QWBZP, showing a certain dose-response relationship. In this experiment, it was concluded that the addition of sucrose might also further lead to intestinal inflammation and the disruption of the intestinal mucosal barrier, and the production of metabolites SCFAs.

Discussion

The addition of sucrose might also further lead to intestinal inflammation and the disruption of the intestinal mucosal barrier, and the production of metabolites SCFAs. However, these findings still need to be verified in a more extensive study. The effect of adding the sweetener sucrose on the efficacy of Chinese herbal medicine in treating diseases also still needs more research.

Effect of different sweeteners on the quality, fatty acid and volatile flavor compounds of braised pork

This study aimed to assess how several sweeteners (white sugar, Siraitia grosvenorii fruit, mogrosides, and stevia glycoside) affected the flavor, fatty acid composition, and quality of braised pork. The findings indicated that braised meat prepared with sweeteners differed from typical braised pork. When simmered for 60 min, the typical braised pork with white granulated sugar exhibited a significant cooking loss (CL) and little water content. Significantly more than in the group containing Siraitia grosvenorii, mogroside, and stevia glycoside, the Thiobarbituric acid (TBARS) value increased by 14.39% (P < 0.05). The sample in the group that included mogroside had a low CL rate. After 40 min of stewing, the lean pork has the highest L* value, but the 60-min stew sample is nicely colored and stretchy. Mogroside can prevent protein, and lipid oxidation, is thermally stable and reduces CL during stewing. Additionally, Siraitia grosvenorii and stevia glycosides help prevent oxidation from intensifying during stewing. When Siraitia grosvenorii is added, lipid oxidation is significantly inhibited, and stevia glycosides are more beneficial for enhancing meat color. With an increase in heating time, the fatty acids in braised pork reduced; the unsaturated fatty acid (UFA) of the Siraitia grosvenorii fruit (SF) and mg group also fell somewhat, and the UFA: SFA ratio was higher than that of the white sugar (WS) group. The SFA content of the braised meat in the stevia glycoside group was higher than that of the WS group. In all, 75 volatile flavor elements in braised pork were discovered by Gas chromatography-ion mobility spectrometry (GC-IMS). The sweetener increased alcohols, esters, and acids in the braised pork. As stewing time increased, ketones decreased, but aldehydes and esters increased. The pork formed antioxidant peptides with great nutritional value after cooking. Braised pork with mogroside and stevia glycoside additions primarily have some protein color protection and antioxidant effects. This study may offer fresh perspectives on applying natural sweeteners and enhancing braised pork’s flavor.

Acute and Sub-Chronic Exposure to Artificial Sweeteners at the Highest Environmentally Relevant Concentration Induce Less Cardiovascular Physiology Alterations in Zebrafish Larvae

Artificial sweeteners are widely used food ingredients in beverages and drinks to lower calorie intake which in turn helps prevent lifestyle diseases such as obesity. However, as their popularity has increased, the release of artificial sweetener to the aquatic environment has also increased at a tremendous rate. Thus, our study aims to systematically explore the potential cardiovascular physiology alterations caused by eight commercial artificial sweeteners, including acesulfame-K, alitame, aspartame, sodium cyclamate, dulcin, neotame, saccharine and sucralose, at the highest environmentally relevant concentration on cardiovascular performance using zebrafish (Danio rerio) as a model system. Embryonic zebrafish were exposed to the eight artificial sweeteners at 100 ppb and their cardiovascular performance (heart rate, ejection fraction, fractional shortening, stroke volume, cardiac output, heartbeat variability, and blood flow velocity) was measured and compared. Overall, our finding supports the safety of artificial sweetener exposure. However, several finding like a significant increase in the heart rate and heart rate variability after incubation in several artificial sweeteners are noteworthy. Biomarker testing also revealed that saccharine significantly increase the dopamine level in zebrafish larvae, which is might be the reason for the cardiac physiology changes observed after saccharine exposure.

Effect of short-term intake of four sweeteners on feed intake, solution consumption and neurotransmitters release on mice

This study focused on the effect of short-term intake of sweeteners on feed intake, solution consumption and neurotransmitters release on mice. The results showed that the free drinking of 10 mM sucralose solution, 100 mM maltose solution, 3 mM saccharin solution and 3 g/L stevioside solution for 32 days will not affect the normal development of the body weight and feed intake of the mice. The consumption of maltose solution was significantly higher than that of the other sweeteners. The leptin and insulin levels increased significantly after the short-term intake of these four sweeteners. The dopamine (DA) content in the whole brain of the mice increased significantly only in the maltose group. These results indicate that the short-term intake of the preferred concentrations of maltose, stevioside, sucralose and saccharin will not affect the body weight and feed intake of the mice. Mice prefer maltose solution to other sweeteners solutions. The 100 mM maltose solution and 3 mM saccharin solution could result in the oxidative stress on mice after 32 days' short-term intake. Compared with other sweeteners, only sugars that could be broken down into small molecules of glucose might have a positive effect on dopamine levels.

Effect and mechanism of high-fat diet on the preference for sweeteners on mice

BACKGROUND

Male Kunming mice were divided into a normal diet group (control group) and a high-fat diet group (HF group) (185 g·kg^-1 protein, 600 g·kg^-1 fat and 205 g·kg^-1 carbohydrate). After 8 weeks' feeding, behavioral indicators and biochemical indicators in serum were determined. The double-bottle preference experiment was used to study the preferences of mice for five sweeteners. The monoamine neurotransmitter content, gene expression related to dopamine (DA), and opioid receptors were also determined.

RESULTS

The body weight of the mice in the HF group increased significantly (P < 0.05) after 36 days compared with the control group. The feed intake of the HF group increased sharply in the first 12 days, and then it became basically unchanged. The preference of the HF group for all of the five sweeteners was highly significantly lower (P < 0.01) than that of the control group. Depression-related behavior was observed in the HF group mice. The triglyceride (TG), total cholesterol (TC), and low-density lipoprotein cholesterol (LDLC) content in the HF group were very much higher (P < 0.01) than those of the control group. The gene expression related to DA and opioid receptor in the HF group was significantly lower than that of the control group, except for preproenkephalin (PENK).

CONCLUSIONS

In summary, this study suggested that a long-term high-fat diet could result in a decrease in the preference for sweeteners and could result in a state of reward hypofunction in mice. © 2020 Society of Chemical Industry.

Sucralose and Cardiometabolic Health: Current Understanding from Receptors to Clinical Investigations

The excess consumption of added sugar is consistently found to be associated with weight gain, and a higher risk of type 2 diabetes mellitus, coronary heart disease, and stroke. In an effort to reduce the risk of cardiometabolic disease, sugar is frequently replaced by low- and null-calorie sweeteners (LCSs). Alarmingly, though, emerging evidence indicates that the consumption of LCSs is associated with an increase in cardiovascular mortality risk that is amplified in those who are overweight or obese. Sucralose, a null-caloric high-intensity sweetener, is the most commonly used LCS worldwide, which is regularly consumed by healthy individuals and patients with metabolic disease. To explore a potential causal role for sucralose in increased cardiovascular risk, this present review summarizes the preclinical and clinical data from current research detailing the effects of sucralose on systems controlling food intake, glucose homeostasis, and gut microbiota.

Effect of short-term intake of high- and low-concentrations of sucrose solution on the neurochemistry of male and female mice

The effect of short-term intake of high- and low-concentrations of sucrose solution on the neurochemistry of male and female mice was studied. The body weight, feed intake, sucrose solution consumption and brain monoamine neurotransmitters were determined after 34 days' intake of 1% and 8% sucrose solutions. The gene expression and protein levels related to dopamine and opioids were also determined. The results showed that the intake of 1% and 8% sucrose solution for 34 days did not cause significant changes in the weight development of both male and female mice. The preference for sucrose varies with sex. Both males and females had greater preference for the high concentration sucrose solution than the low concentration sucrose solution. The continuous intake of sucrose stimulated the release of monoamine neurotransmitters (DA, 5-HT, NE) in the brains of mice, and the reward effect of 8% sucrose solution is significantly higher than that of 1% sucrose solution. The sex of mice did not affect the release of neurotransmitters. The gene expressions of D1 and D2 were up-regulated in the 1% sucrose group of male mice, while the OPRM1 gene expression was down-regulated. The expression of these three genes in the 8% sucrose group of male mice was all down-regulated, while the gene expressions of D1 and D2 in the 1% and 8% sucrose group (p < 0.05) of female mice were both up-regulated.