Search Results (64)

Enhanced colony nutrition can support brood development, resulting in better physiological conditions and increased resilience in adult honey bees, particularly under stress. This study investigated the effects of colony nutrition and adult dietary supplementation with green propolis on bee health under fungicide exposure. Colonies were managed under food restriction or nutritional supplementation for 22 weeks. Newly emerged bees from each colony were then caged and fed protein diets consisting of honey-pollen patties contaminated or not with fungicide, and sucrose sugar syrup with or without aqueous green propolis extract. Bees from supplemented colonies showed greater body weight, higher hemolymph protein levels, and higher consumption of protein food after seven days in cages. Fungicide exposure reduced hemolymph protein levels, altered the expression of detoxification and immune-related genes, and significantly decreased bee survival. Interestingly, propolis supplementation alone changed gene expression patterns and slightly reduced longevity compared to bees not exposed to propolis or fungicide. However, under fungicide stress, bees that ingested propolis survived longer, indicating a protective effect. While colony nutritional supplementation clearly promotes honey bee resilience against fungicide exposure, feeding propolis also showed promising effects, though further studies are needed to determine an optimal dietary concentration. Full article

The global obesity and metabolic syndrome epidemic have accelerated demand for reduced-sugar food, prompting the food industry to adopt functional sugar alcohols as sucrose substitutes. Threitol is a four-carbon sugar alcohol and an isomer of erythritol. However, there is a scarcity of studies reporting on the edible safety of threitol. This study assessed threitol’s toxicological and metabolic properties. Acute oral administration (10 g/kg) caused no mortality or abnormalities in mice. Repeated 28-day exposure revealed no behavioral or histopathological alterations, with negative outcomes in three genotoxicity tests. Metabolic studies in rats demonstrated that the majority of ingested threitol is excreted in the urine within 24 h. Sensory evaluation indicated threitol’s sweetness equivalence to sucrose, exceeding erythritol and allulose. Notably, 16S rRNA sequencing revealed gut microbiota modulation in threitol-fed mice, indicating potential intestinal health benefits. These integrated findings establish threitol’s preclinical safety and support its development as a novel low-calorie sweetener. Full article

Staphylococcus aureus, an opportunistic bacterium found in the oral cavity, has been reported as a causative agent of infective endocarditis and pneumonia. Salt is an essential mineral for cell maintenance in the human body. This study was conducted to clarify how salt affects the formation of biofilms by S. aureus and Streptococcus mutans, pathogens implicated in dental caries. Bacteria were cultivated with various concentrations of NaCl on a 96-well microtiter plate in tryptic soy broth with 0.25% sucrose or 0.25% glucose (TSBs and TSBg, respectively) for 16 h. The effects of glucosyltransferase in S. mutans membrane vesicles (MVs) and extracellular DNA during biofilm formation were also analyzed. S. aureus biofilms were induced by 0.004–0.25 M NaCl but not by NaCl at concentrations greater than 0.25 M in TSBs. The mixed S. aureus and S. mutans biofilms gradually grew and were constructed by dead cells in a NaCl concentration-dependent manner in both TSBs and TSBg. Moreover, biofilms were slightly induced by glucan generation mediated by the glucosyltransferases in MVs under high-salinity conditions. The formation of mixed-species S. aureus and S. mutans biofilms increased in the presence of both extracellular DNA and MVs. Therefore, extracellular DNA, MVs, and dead cells are factors that promote S. aureus biofilm formation under harsh conditions containing NaCl. The sugar (sucrose and glucose) ingestion-induced S. mutans biofilm may be a risk factor for infection by opportunistic pathogens such as S. aureus in individuals who consume food and drinks containing high concentrations of salt. Full article

Background: Roux-en-Y gastric bypass (RYGB) surgery results in weight reduction and decreased energy intake and can ameliorate type 2 diabetes. These beneficial effects are usually attributed to changes in hunger and satiety and relatively rapid improvements in glycemic control, but these effects may depend on dietary adherence. The aim of this study is to investigate the relatively early effects of RYGB surgery on weight reduction (by focusing on eating patterns) and glycemic control in rats subjected to a healthy maintenance diet or an unhealthy Western-style diet. Methods: Rats were fed a high-fat diet with added sucrose (HF/S) or a low-fat (LF) diet. Body weight, high-resolution tracking of meal-related parameters, and glucose regulation after overnight fasting and during a mixed meal tolerance test (MMTT; 2 mL sweet/condensed milk) were measured before and after RYGB (RYGB+) or sham surgery (RYGB−). Results: HF/S feeding led to an increased body weight just before RYGB surgery, but it also caused enhanced weight loss following RYGB, which led to similar body weights in the HF/S and LF diet groups twenty-four days post-operatively. RYGB surgery and diet dependently and independently influenced meal-related parameter outcomes, where both RYGB+ and HF/S feeding resulted in shorter meal duration (p < 0.01), higher ingestion rates (p < 0.001), and increased satiety ratio (p < 0.05), especially in the HF/S diet group subjected to RYGB. While RYGB surgery generally improved baseline glycemic parameters including HOMA-IR (p < 0.01), it often interacted with diet to affect MMTT-induced hyperglycemia (p < 0.05), beta-cell sensitivity (p < 0.01), and the insulinogenic index (p < 0.01), with the LF rats overall maintaining better glycemic control than the HF/S-fed rats. Conclusions: This study shows the importance of controlling diet after RYGB surgery, as diet type significantly influences ingestive behavior, post-prandial glucose regulation, beta-cell sensitivity, and glucose tolerance after RYGB. Full article

Objectives: This study primarily aimed to examine the optimal amount of carbohydrates in the effects of high-isomaltulose and high-sucrose ingestion compared with low-sucrose ingestion on blood glucose levels. The secondary objective was to assess the changes in blood glucose levels that may impact golf-related performance. Methods: This study included 29 healthy male competitive golfers playing 18 holes. These participants were randomly assigned to the low-sucrose (LSUC, 30.9 g/h of carbohydrates), high-sucrose (HSUC, 44.2 g/h of carbohydrates), and high-isomaltulose (HISO, 44.5 g/h of carbohydrates) groups. They were required to continuously consume the test food during the round. Assessment items included blood glucose, golf performance, urinary urea nitrogen, subjective ratings (concentration, fatigue, and relaxation), and anxiety ratings. A main effect of the test meal of changes in interstitial glucose concentration was determined. Results: The HSUC had significantly more interstitial glucose than the HISO and LSUC, while the HISO group had a much lower decrease in urine urea nitrogen than the LSUC group. In subjective fatigue, the main effect of the test diet was observed, and the HSUC and HISO showed significantly lower values than the LSUC after 18 h. Conclusions: Compared with low-carbohydrate intake, high-carbohydrate intake during a round of golf-maintained the blood glucose levels and prevented fatigue. Therefore, this study indicates that competitive golfers need a high-carbohydrate intake of approximately 44 g/h for energy intake during a round of golf. Full article

Background: Neonatal rats that receive sucrose during a critical postnatal period (CP, days 12 to 28) develop hypertension by the time they reach adulthood. Inflammation might contribute to changes during this period and could be associated with variations in the vascular smooth muscle (VSMC) phenotype. Objective: We studied changes in inflammatory pathways that could underlie the expression of the secretory phenotype in the VSMC in the thoracic aorta of rats that received sucrose during CP. Methods: We analyzed histological changes in the aorta and the expression of the COX-2, TLR4, iNOS, eNOS, MMP-2 and -9, and β- and α-actin, the quantities of TNF-α, IL-6, and IL-1β using ELISA, and the levels of fatty acids using gas chromatography. Results: The aortic wall presented disorganization, decellularization, and wavy elastic fibers and an increase in the lumen area. The α- and β-actin expressions were decreased, while COX-2, TLR4, TNF-α, and the activity of IL-6 were increased. Oleic acid was increased in CP in comparison to the control group. Conclusions: There is transient hypertension at the end of the CP that is accompanied by inflammation and a change in the phenotype of VSMC to the secretory phenotype. The inflammatory changes could act as epigenetic signals to determine the development of hypertension when animals reach adulthood. Full article

Allergic dermatitis is a skin disease with growing prevalence worldwide that has been associated with diets high in fats and sugars. Regular consumption of sucrose-containing beverages may increase the risk for several health problems, including allergic diseases and particularly asthma, but the association between sucrose consumption and allergic dermatitis is understudied. We investigated the effects of sucrose solution intake on allergic contact dermatitis in rats and found early exacerbation of 2,4-dinitrofluorobenzene (DNFB)-induced disease symptoms and altered composition of the gut microbiota after 14 d of intake. The levels of short-chain fatty acids—produced by fermentation by the intestinal microbiota—were not affected in the cecal contents and feces but decreased in the blood; this effect was especially notable for acetate. To restore blood acetate concentrations, triacetin was mixed with a 10% sucrose solution and fed to the rat model. This strategy prevented the early exacerbation of DNFB-induced symptoms. The decreased absorption of short-chain fatty acids from the intestinal lumen was not linked to the decreased expression of short-chain fatty acid transporters in the small intestine; instead, the mechanism involves a reduction in the sodium concentration in the intestinal lumen due to increased expression of sodium–glucose transporter 1 (SGLT1). Full article

Non-alcoholic fatty liver disease (NAFLD), a significant cause of chronic liver disease, presents a considerable public health concern. Despite this, there is currently no treatment available. This study aimed to investigate dietary flaxseed in the JCR:LA-corpulent rat strain model of NAFLD. Both obese male and female rats were studied along with their lean counterparts after 12 weeks of ingestion of a control diet, or control diet with flaxseed, or high fat, high sucrose (HFHS), or HFHS plus flaxseed. Obese rats showed higher liver weight and increased levels of cholesterol, triglyceride, and saturated fatty acid, which were further elevated in rats on the HFHS diet. The HFHS diet induced a significant two-fold elevation in the plasma levels of both aspartate aminotransferase and alanine aminotransferase in the obese male and female rats. Including flaxseed in the HFHS diet significantly lowered liver weight, depressed the plasma levels of both enzymes in the obese male rats, and reduced hepatic cholesterol and triglyceride content as well as improving the fatty acid profile. In summary, including flaxseed in the diet of male and female obese rats led to an improved lipid composition in the liver and significantly reduced biomarkers of tissue injury despite consuming a HFHS chow. Full article

Nigella sativa (NS) is a native herb consumed habitually in several countries worldwide, possessing manifold therapeutic properties. Among them, anti-inflammatory features have been reported, presumably relating to mechanisms involved in the nuclear factor kappa-B pathway, among others. Given the observed association between neuroimmune factors and mental illness, the primary aim of the present study was to examine the effects of chronic NS use on manic-like behavior in rats, as well as analyze levels of brain inflammatory mediators following NS intake. Using male and female rats, baseline tests were performed; thereafter, rats were fed either regular food (control) or NS-containing food (treatment) for four weeks. Following intervention, behavioral tests were induced (an open field test, sucrose consumption test, three-chamber sociality test, and amphetamine-induced hyperactivity test). Subsequently, brain samples were extracted, and inflammatory mediators were evaluated, including interleukin-6, leukotriene B4, prostaglandin E2, tumor necrosis factor-α, and nuclear phosphorylated-p65. Our findings show NS to result in a marked antimanic-like effect, in tandem with a positive modulation of select inflammatory mediators among male and female rats. The findings reinforce the proposed therapeutic advantages relating to NS ingestion. Full article

The aim of this work was to evaluate possible mechanisms involved in the protective effect of N-acetyl-L-cysteine (NAC) on hepatic endocrine-metabolic, oxidative stress, and inflammatory changes in prediabetic rats. For that, normal male Wistar rats (60 days old) were fed for 21 days with 10% sucrose in their drinking water and 5 days of NAC administration (50 mg/kg, i.p.) and thereafter, we determined: serum glucose, insulin, transaminases, uric acid, and triglyceride levels; hepatic fructokinase and glucokinase activities, glycogen content, lipogenic gene expression; enzymatic and non-enzymatic oxidative stress, insulin signaling pathway, and inflammatory markers. Results showed that alterations evinced in sucrose-fed rats (hypertriglyceridemia, hyperinsulinemia, and high liver fructokinase activity together with increased liver lipogenic gene expression and oxidative stress and inflammatory markers) were prevented by NAC administration. P-endothelial nitric oxide synthase (P-eNOS)/eNOS and pAKT/AKT ratios, decreased by sucrose ingestion, were restored after NAC treatment. In conclusion, the results suggest that NAC administration improves glucose homeostasis, oxidative stress, and inflammation in prediabetic rats probably mediated by modulation of the AKT/NOS pathway. Administration of NAC may be an effective complementary strategy to alleviate or prevent oxidative stress and inflammatory responses observed in type 2 diabetes at early stages of its development (prediabetes). Full article

The Asian citrus psyllid (ACP) is a citrus pest and insect vector of “Candidatus Liberibacter asiaticus”, the causal agent of citrus greening disease. Double-stranded RNA (dsRNA) biopesticides that trigger RNA interference (RNAi) offer an alternative to traditional insecticides. Standardized laboratory screening of dsRNA requires establishing the minimal effective concentration(s) that result in effective RNAi “penetrance” and trigger RNAi, resulting in one or more measurable phenotypes, herein, significant gene knockdown and the potential for mortality. In this study, knockdown was evaluated for a range of dsRNA concentrations of three ACP candidate genes, clathrin heavy chain (CHC), vacuolar ATPase subunit A (vATPase-A), and sucrose non-fermenting protein 7 (Snf7). Gene knockdown was quantified for ACP teneral adults and 3rd instar nymphs allowed a 48 h ingestion-access period (IAP) on 10, 50,100, 200, and 500 ng/µL dsRNA dissolved in 20% sucrose followed by a 5-day post-IAP on orange jasmine shoots. Significant gene knockdown (p < 0.05) in ACP third instar nymphs and adults ranged from 12–34% and 18–39%, 5 days post-IAP on dsRNA at 10–500 and 100–500 ng/µL, respectively. The threshold concentration beyond which no significant gene knockdown and adult mortality was observed post-48 h IAP and 10-day IAP, respectively, was determined as 200 ng/µL, a concentration indicative of optimal RNAi penetrance. Full article

Melipona scutellaris is a Brazilian stingless bee that is important for pollinating wild flora and agriculture crops. Fungicides have been widely used in agriculture, and floral residues can affect forager bees. The goal of our study was to evaluate the effects of sublethal concentrations of pyraclostrobin on the midgut ultrastructure of M. scutellaris forager workers. The bees were collected from three non-parental colonies and kept under laboratory conditions. The bees were orally exposed continuously for five days to pyraclostrobin in syrup at concentrations of 0.125 ng a.i./µL (FG1) and 0.005 ng a.i./µL (FG2). The control bees (CTL) were fed a no-fungicide sucrose solution, and the acetone solvent control bees (CAC) received a sucrose solution containing acetone. At the end of the exposure, the midguts were sampled, fixed in Karnovsky solution, and routinely processed for transmission electron microscopy. Ultrastructural analysis demonstrated that both the fungicide concentrations altered the midgut, such as cytoplasmic vacuolization (more intense in FG1), the presence of an atypical nuclear morphology, and slightly dilated mitochondrial cristae in the bees from the FG1 and FG2 groups (both more intense in FG1). Additionally, there was an alteration in the ultrastructure of the spherocrystals (FG1), which could be the result of cellular metabolism impairment and the excretion of toxic metabolites in the digestive cells as a response to fungicide exposure. The results indicate that ingested pyraclostrobin induced cytotoxic effects in the midgut of native stingless bees. These cellular ultrastructural responses of the midgut are a prelude to a reduced survival rate, as observed in previous studies. Full article

Trichome is a hair-like structure involved in mechanical and chemical defenses of plants against herbivorous insects. Nicotiana benthamiana, a wild tobacco plant, has well-developed glandular trichomes that secrete sugar esters with potent repellent and insecticidal properties. However, there is a lack of information about the effectiveness of trichome extract in the control of plant-sapping insects. The objective of this study was to investigate the effects of N. benthamiana trichome exudates on Bemisia tabaci MED (Gennadius) (Hemiptera: Aleyrodidae), a highly destructive insect pest that poses significant threats to both vegetable and ornamental plants globally. First, we determined the host preference and mortality of B. tabaci adults using the choice test and feeding assay towards tomato and N. benthamiana plants. B. tabaci preferred tomato over N. benthamiana plants. Second, we extracted N. benthamiana trichome exudates by washing the leaves with either water or ethanol and evaluated their oral toxicities against B. tabaci adults using a parafilm feeding chamber containing 20% sucrose solution. Oral ingestion of both extracts significantly increased mortality in a concentration-dependent manner. Oral ingestion of ethanol-washed 10% trichome extract caused >60% mortality in B. tabaci adults after 36 h. Third, trichome exudates were concentrated by drying to obtain a powder form, which was more potent in killing whiteflies than the liquid form. Oral ingestion of 1% trichome powder was completely lethal to B. tabaci within 36 h. N. benthamiana trichome exudates are highly toxic to B. tabaci through oral ingestion, suggesting that N. benthamiana can be used as a potential natural pesticide for whitefly management. Full article

The increasing frequency of processed food consumption has led to the higher ingestion of sugar, increasing the risk of chronic diseases, such as obesity. Yeast hydrolysates (YHs) inhibit body fat accumulation. However, the action mechanism of YH in relation to high-sugar diet-induced obesity is still unclear. Therefore, this study aimed to evaluate the biological effects of YH on lipid accumulation and verify behavioral changes and carbohydrate metabolic gene regulation in high-sugar diet-fed fruit flies. Adult male flies (Drosophila melanogaster; 2–5 days old) were exposed to 20% sucrose for obesity induction. In high-sugar-fed Drosophila, the effect of YH was compared with that of yeast extract. The effects of YH on body conditions and lipid droplet size were quantified and analyzed. Behavioral factors were evaluated by analyzing circadian rhythm patterns and neurotransmitter content, and a molecular approach was used to analyze the expression of metabolism-related genes. Dietary supplementation with YH did not reduce total sugar content, but significantly decreased the triglyceride (TG) levels in Drosophila. A behavioral analysis showed that the total number of night-time activities increased significantly with YH treatment in a dose-dependent manner. In addition, YH effectively regulated the gene expression of insulin-like peptides related to carbohydrate metabolism as well as genes related to lipogenesis. The TG content was significantly reduced at a YH concentration of 0.5%, confirming that the active compound in YH effectively suppresses fat accumulation. These findings support that YH is a potential anti-obesity food material via regulating carbohydrate metabolism in Drosophila. Full article

Sugar-induced metabolic imbalances are a major health problem since an excessive consumption of saccharides has been linked to greater obesity rates at a global level. Sucrose, a disaccharide composed of 50% glucose and 50% fructose, is commonly used in the food industry and found in a range of fast, restaurant, and processed foods. Herein, we investigated the effects of a TRPC4/TRPC5 blocker, ML204, in the metabolic imbalances triggered by early exposure to sucrose-enriched diet in mice. TRPC4 and TRPC5 belong to the family of non-selective Ca⁺² channels known as transient receptor potential channels. High-sucrose (HS)-fed animals with hyperglycaemia and dyslipidaemia, were accompanied by increased body mass index. mesenteric adipose tissue accumulation with larger diameter cells and hepatic steatosis in comparison to those fed normal diet. HS mice also exhibited enhanced adipose, liver, and pancreas TNFα and VEGF levels. ML204 exacerbated hyperglycaemia, dyslipidaemia, fat tissue deposition, hepatic steatosis, and adipose tissue and liver TNFα in HS-fed mice. Normal mice treated with the blocker had greater hepatic steatosis and adipose tissue cell numbers/diameter than those receiving vehicle, but showed no significant changes in tissue inflammation, glucose, and lipid levels. The results indicate that TRPC4/TRPC5 protect against the metabolic imbalances caused by HS ingestion. Full article