Genetics and diet shape the relationship between islet function and whole-body metabolism.

Despite the fact that genes and the environment are known to play a central role in islet function, our knowledge of how these parameters interact to modulate insulin secretory function remains relatively poor. Presently, we performed ex vivo glucose-stimulated insulin secretion and insulin content assays in islets of 213 mice from 13 inbred mouse strains on chow, western diet, and ketogenic diet. Strikingly, among these 13 strains, islets from the commonly used C57BL/6J mouse strain were the least glucose responsive. Using matched metabolic phenotyping data, we performed correlation analyses of inter-islet parameters and found a positive correlation between basal and glucose-stimulated insulin secretion, but no relationship between insulin secretion and insulin content. Using in vivo metabolic measures, we found that metabolic health determines the relationship between ex vivo islet insulin secretion and fasting plasma insulin. Finally, we showed that islet glucose-stimulated insulin secretion decreased with ketogenic diet in almost all strains, concomitant with broader phenotypic changes, such as increased adiposity and glucose intolerance. This is an important finding as it should caution against the application of the ketogenic diet for beta-cell health. Together these data offer key insights into the intersection of diet and genetic background on islet function and whole-body metabolism.

Metabolic sensing in AgRP regulates sucrose preference and dopamine release in the nucleus accumbens.

Hunger increases the motivation for calorie consumption, often at the expense of low-taste appeal. However, the neural mechanisms integrating calorie-sensing with increased motivation for calorie consumption remain unknown. Agouti-related peptide (AgRP) neurons in the arcuate nucleus of the hypothalamus sense hunger, and the ingestion of caloric solutions promotes dopamine release in the absence of sweet taste perception. Therefore, we hypothesised that metabolic-sensing of hunger by AgRP neurons would be essential to promote dopamine release in the nucleus accumbens in response to caloric, but not non-caloric solutions. Moreover, we examined whether metabolic sensing in AgRP neurons affected taste preference for bitter solutions under conditions of energy need. Here we show that impaired metabolic sensing in AgRP neurons attenuated nucleus accumbens dopamine release in response to sucrose, but not saccharin, consumption. Furthermore, metabolic sensing in AgRP neurons was essential to distinguish nucleus accumbens dopamine response to sucrose consumption when compared with saccharin. Under conditions of hunger, metabolic sensing in AgRP neurons increased the preference for sucrose solutions laced with the bitter tastant, quinine, to ensure calorie consumption, whereas mice with impaired metabolic sensing in AgRP neurons maintained a strong aversion to sucrose/quinine solutions despite ongoing hunger. In conclusion, we demonstrate normal metabolic sensing in AgRP neurons drives the preference for calorie consumption, primarily when needed, by engaging dopamine release in the nucleus accumbens.

Sugar beet PMT5a and STP13 carriers suitable for proton-driven plasma membrane sucrose and glucose import in taproots.

Sugar beet (Beta vulgaris) is the major sugar-producing crop in Europe and Northern America, as the taproot stores sucrose at a concentration of around 20%. Genome sequence analysis together with biochemical and electrophysiological approaches led to the identification and characterization of the TST sucrose transporter driving vacuolar sugar accumulation in the taproot. However, the sugar transporters mediating sucrose uptake across the plasma membrane of taproot parenchyma cells remained unknown. As with glucose, sucrose stimulation of taproot parenchyma cells caused inward proton fluxes and plasma membrane depolarization, indicating a sugar/proton symport mechanism. To decipher the nature of the corresponding proton-driven sugar transporters, we performed taproot transcriptomic profiling and identified the cold-induced PMT5a and STP13 transporters. When expressed in Xenopus laevis oocytes, BvPMT5a was characterized as a voltage- and H+-driven low-affinity glucose transporter, which does not transport sucrose. In contrast, BvSTP13 operated as a high-affinity H+/sugar symporter, transporting glucose better than sucrose, and being more cold-tolerant than BvPMT5a. Modeling of the BvSTP13 structure with bound mono- and disaccharides suggests plasticity of the binding cleft to accommodate the different saccharides. The identification of BvPMT5a and BvSTP13 as taproot sugar transporters could improve breeding of sugar beet to provide a sustainable energy crop.

Direct and indirect responses of the Arabidopsis transcriptome to an induced increase in trehalose 6-phosphate.

Trehalose 6-phosphate (Tre6P) is an essential signal metabolite that regulates the level of sucrose, linking growth and development to the metabolic status. We hypothesized that Tre6P plays a role in mediating the regulation of gene expression by sucrose. To test this, we performed transcriptomic profiling on Arabidopsis (Arabidopsis thaliana) plants that expressed a bacterial TREHALOSE 6-PHOSPHATE SYNTHASE (TPS) under the control of an ethanol-inducible promoter. Induction led to a 4-fold rise in Tre6P levels, a concomitant decrease in sucrose, significant changes (FDR ≤ 0.05) of over 13,000 transcripts, and two-fold or larger changes of over 5000 transcripts. Comparison with nine published responses to sugar availability allowed some of these changes to be linked to the rise in Tre6P, while others were probably due to lower sucrose or other indirect effects. Changes linked to Tre6P included repression of photosynthesis-related gene expression and induction of many growth-related processes including ribosome biogenesis. About 500 starvation-related genes are known to be induced by SUCROSE-NON-FERMENTING-1-RELATED KINASE 1 (SnRK1). They were largely repressed by Tre6P in a manner consistent with SnRK1 inhibition by Tre6P. SnRK1 also represses many genes that are involved in biosynthesis and growth. These responded to Tre6P in a more complex manner, pointing toward Tre6P interacting with other C-signaling pathways. Additionally, elevated Tre6P modified the expression of genes encoding regulatory subunits of the SnRK1 complex and TPS class II and FCS-LIKE ZINC FINGER proteins that are thought to modulate SnRK1 function and genes involved in circadian, TARGET OF RAPAMYCIN-, light, abscisic acid, and other hormone signaling.

Efficacy of sucrose application in minimizing pain perception related to dental injection in children aged 3 to 9 years: a randomized control trial.

Background: Dental fear and anxiety are significant challenges in managing behavior in children. Oral administration of sucrose or sweet-tasting solutions has shown effectiveness in reducing procedural pain in infants and neonates. This study aimed to investigate whether pre-application of sucrose solution had an effect on minimizing pain perception during injection and to assess the potential impact of the child's age and sweet preference. Methods: A randomized control clinical trial was conducted on 60 children aged 3-9 years requiring buccal infiltration injections. Following parental consent, demographic data of the children were recorded. Sweet preferences was assessed using a modified forced-choice test. Children were equally and randomly allocated into study (sucrose) and control groups using a lottery method. Sucrose solution or distilled water, respectively, was applied to the lateral surface of the tongue for 2 min. Topical anesthetic was applied at the site of injection, followed by local anesthesia administration. The children rinsed their mouths thrice with water immediately after anesthetic injection. A video was recorded during injection which was then scored by three blinded examiners on the Sound Eye Motor (SEM) scale. The children also self-evaluated using Wong-Baker Faces Pain Rating Scale (WBFPS). Results: The mean SEM scores and WBFPS scores were analyzed using the Kruskall-Wallis test. The mean SEM score in the study group was 1.37 ± 0.61, compared to 3.17 ± 0.87 in the control group, showing a statistically significant difference (P < 0.001). Mean pain scores assessed by WBFPS in the study group were 0.60 ± 1.4, while in the control group, they were 6.27 ± 2.33, also showing a statistically significant difference (P < 0.001). Children with a sweet preference demonstrated a subjective reduction in pain perception. Conclusion: Application of sucrose before dental injections in children helps to minimize pain upon injection across all age groups.

Cardiac dysfunction in sucrose-fed rats is associated with alterations of phospholamban phosphorylation and TNF-α levels.

INTRODUCTION: High sucrose intake is linked to cardiovascular disease, a major global cause of mortality worldwide. Calcium mishandling and inflammation play crucial roles in cardiac disease pathophysiology. OBJECTIVE: Evaluate if sucrose-induced obesity is related to deterioration of myocardial function due to alterations in the calcium-handling proteins in association with proinflammatory cytokines. METHODS: Wistar rats were divided into control and sucrose groups. Over eight weeks, Sucrose group received 30% sucrose water. Cardiac function was determined in vivo using echocardiography and in vitro using papillary muscle assay. Western blotting was used to detect calcium handling protein; ELISA assay was used to assess TNF-α and IL-6 levels. RESULTS: Sucrose led to cardiac dysfunction. RYR2, SERCA2, NCX, pPBL Ser16 and L-type calcium channels were unchanged. However, pPBL-Thr17, and TNF-α levels were elevated in the S group. CONCLUSION: Sucrose induced cardiac dysfunction and decreased myocardial contractility in association with altered pPBL-Thr17 and elevated cardiac pro-inflammatory TNF-α.

[Evaluation of the efficacy and safety of intravenous infusion of ferric derisomaltose in the treatment of iron deficiency anemia: a single-center retrospective analysis].

Objective: To investigate the clinical efficacy and safety of ferric derisomaltose injection versus iron sucrose injection in the treatment of iron deficiency anemia (IDA) . Methods: A total of 120 patients with iron deficiency anemia admitted from June 2021 to March 2023 were given intravenous iron supplementation with ferric derisomaltose to assess the efficacy and safety of hemoglobin (HGB) elevation before and after treatment. Simultaneously, the clinical effects of iron supplementation with iron sucrose were compared to those of inpatient patients during the same period. Results: Baseline values were comparable in both groups. Within 12 weeks of treatment, the elevated HGB level in the ferric derisomaltose group was higher than that of the iron sucrose group, with a statistical difference at all time points, and the proportion of HGB increased over 20 g/L in the patients treated for 4 weeks was higher (98.7%, 75.9% ). During the treatment with ferric derisomaltose and iron sucrose, the proportion of mild adverse reactions in the ferric derisomaltose group was slightly lower than that of the iron sucrose group, and neither group experienced any serious adverse reactions. The patients responded well to the infusion treatment, with no reports of pain or pigmentation at the injection site. Conclusion: The treatment of IDA patients with ferric derisomaltose has a satisfactory curative effect, with the advantages of rapidity, accuracy, and safety. Therefore, it is worthy of widespread clinical use.

Effects of Highly Palatable Diet on motivation for food and resistance to punishment in rats: Role of sex and age of exposure.

Exposure to highly palatable food is believed to induce behavioral and neurobiological changes that may produce addiction-like behavior and increase the risks of obesity and overweight. Studies in rodents have led to conflicting results suggesting that several factors such as sex and age of exposure contribute to the development of maladaptive behaviors towards food. In addition, it is not clear whether effects of exposure to highly palatable diets (HPD) persist after their discontinuation, which would indicate long-term risks to develop addiction-like behavior. In this study, we investigated the persistent effects of an intermittent 8-week exposure to HPD in male and female rats as a function of age of exposure (adult and adolescent). We found that intermittent exposure to HPD did not alter body weight, but it affected consumption of standard food during the time of exposure in all groups. In addition, in adults, HPD produced a decrease in the initial baseline responding in FR1 schedules, an effect that persisted for 4 weeks in males but not in female rats. However, we found that exposure to HPD did not affect resistance to punishment measured by progressive shock strength break points or motivation for food as measured by progressive-ratio break points regardless of sex or age of exposure. Altogether, these results do not provide support for the hypothesis that intermittent exposure to HPD produce persistent increases in the vulnerability to develop addiction-like behaviors towards palatable food.

Expression and Function of Connexins in Extracellular Vesicles.

Extracellular vesicles (EVs) are recognized as major vehicles for exchange of information across distant cells and tissues, which have been extensively explored for diagnosis and therapeutic purposes. The presence of multiple connexin (Cx) proteins has been described in EVs, where they might facilitate EV-cell communication. However, quantitative changes in Cx levels and functional assessment of Cx channels have only been established for Cx43. In present work, we provide a detailed description of the protocols we have optimized to assess the expression and permeability of Cx43 channels in EVs derived from cultured cells and human peripheral blood. Particularly, we include some modifications to improve quantitative analysis of EV-Cx43 by enzyme-linked immunosorbent assay (ELISA) and assessment of channel functionality by sucrose-density gradient ultracentrifugation, which can be easily adapted to other Cx family members, leveraging the development of diagnostic and therapeutic applications based on Cx-containing EVs.

Impaired Carbohydrate Metabolism among Women with Chronic Low Back Pain and the Role of Dietary Carbohydrates: A Randomized Controlled Cross-Over Experiment.

Background: Impaired glucose regulation is suggested to be related to chronic low back pain (CLBP), although it is not clear how they interact with each other. Thus, the primary aim of this study was to investigate differences in postprandial glycemic responses (PPGRs) (the first sign of impaired glucose metabolism) to high- (sucrose) and low-glycemic index (GI) (isomaltulose) beverages in normoglycemic women with CLBP and healthy controls (HCs) and explore whether any group that showed greater PPGRs to high-GI beverage intake would benefit when the high-GI beverage was replaced with a low-GI beverage. Secondly, this study aimed to explore the association between PPGR and pain in patients with CLBP. Methods: This study was registered at clinicaltrials.org (NCT04459104) before the start of the study. In this study, 53 CLBP patients and 53 HCs were recruited. After 11-12 h of fasting, each participant randomly received isomaltulose or sucrose. Blood glucose levels were measured during the fasting state and 15, 30, 45, 60, 90, and 120 min after the beverage intake, and each participant underwent experimental pain measures. Results: Compared to the HCs, the CLBP group showed significantly higher PPGRs to sucrose (p < 0.021). Additionally, the CLBP group showed a significantly higher decrease in PPGR (p = 0.045) when comparing PPGR to sucrose with PPGR to isomaltulose. Correlation analysis revealed a positive association between self-reported pain sensitivity and PPGR to sucrose, while there was no association found between any experimental pain measures and glycemic responses. Conclusions: Overall, these findings suggest that normoglycemic CLBP patients might have a higher risk of developing impaired glucose tolerance than the HCs and might benefit more when high-GI foods are replaced with low-GI ones.

Intake of Table Sugar and Their Corresponding Food Sources in Adults from the 2017-2018 Brazilian National Dietary Survey.

Excessive intake of free sugars is associated with adverse health outcomes. Table sugar is one of the main dietary sources of free sugars; however, the amount added by Brazilian consumers in their culinary preparations is unknown. The aims were to estimate the daily intake of table sugar (g/day), its contribution to total energy intake (E%) and the main food groups that contribute to the intake of this sugar in a nationwide multi-ethnic sample of Brazilian adults (2017-2018 Brazilian National Dietary Survey). Based on two 24-h recalls adjusted for the within-person variation, the overall median table sugar intake was 14.3 g/day, corresponding to 3.2 E%. Males, individuals living in rural areas, with low income, low education and experiencing food insecurity had a higher intake of table sugar. The main food sources of table sugar were coffee (55.8%), juice (33.9%), milk-based preparations and smoothies (3.1%), powdered and processed juice (2.7%), whole milk (1.9%), and tea (1.6%). There are no recommendations regarding the limit of table sugar intake, but considering that the WHO limits the intake of free sugars to <10 E%, it is concluded that table sugar intake by Brazilians corresponds to about 30% of the upper recommended daily intake of free sugars.

Analysis of sugar components and identification of SPS genes in citrus fruit development.

Sugar is a primary determinant of citrus fruit flavour, but undergoes varied accumulation processes across different citrus varieties owing to high genetic variability. Sucrose phosphate synthase (SPS), a key enzyme in glucose metabolism, plays a crucial role in this context. Despite its significance, there is limited research on sugar component quality and the expression and regulatory prediction of SPS genes during citrus fruit development. Therefore, we analysed the sugar quality formation process in 'Kiyomi' and 'Succosa', two citrus varieties, and performed a comprehensive genome-wide analysis of citrus CsSPSs. We observed that the accumulation of sugar components significantly differs between the two varieties, with the identification of four CsSPSs in citrus. CsSPS sequences were highly conserved, featuring typical SPS protein domains. Expression analysis revealed a positive correlation between CsSPS expression and sugar accumulation in citrus fruits. However, CsSPS expression displays specificity to different citrus tissues and varieties. Transcriptome co-expression network analysis suggests the involvement of multiple transcription factors in shaping citrus fruit sugar quality through the regulation of CsSPSs. Notably, the expression levels of four CsWRKYs (CsWRKY2, CsWRKY20, CsWRKY28, CsWRKY32), were significantly positively correlated with CsSPSs and CsWRKY20 might can activate sugar accumulation in citrus fruit through CsSPS2. Collectively, we further emphasize the potential importance of CsWRKYs in citrus sugar metabolism, our findings serve as a reference for understanding sugar component formation and predicting CsSPS expression and regulation during citrus fruit development.

Sex-specific transgenerational effects of diet on offspring life history and physiology.

Dietary variation in males and females can shape the expression of offspring life histories and physiology. However, the relative contributions of maternal and paternal dietary variation to phenotypic expression of latter generations is currently unknown. We provided male and female Drosophila melanogaster grandparents with diets differing in sucrose concentration prior to reproduction, and similarly subjected their grandoffspring to the same treatments. We then investigated the phenotypic consequences of this dietary variation among the grandsons and granddaughters. We observed transgenerational effects of dietary sucrose, mediated through the grandmaternal lineage, which mimic the direct effects of sucrose on lifespan, with opposing patterns across sexes; low sucrose increased female, but decreased male, lifespan. Dietary mismatching of grandoffspring-grandparent diets increased lifespan and reproductive success, and moderated triglyceride levels of grandoffspring, providing insights into the physiological underpinnings of the complex transgenerational effects on life histories.

A double-network porous hydrogel based on high internal phase emulsions as a vehicle for potassium sucrose octasulfate delivery accelerates diabetic wound healing.

Diabetic wounds are a difficult medical challenge. Excessive secretion of matrix metalloproteinase-9 (MMP-9) in diabetic wounds further degrades the extracellular matrix and growth factors and causes severe vascular damage, which seriously hinders diabetic wound healing. To solve these issues, a double-network porous hydrogel composed of poly (methyl methacrylate-co-acrylamide) (p(MMA-co-AM)) and polyvinyl alcohol (PVA) was constructed by the high internal phase emulsion (HIPE) technique for the delivery of potassium sucrose octasulfate (PSO), a drug that can inhibit MMPs, increase angiogenesis and improve microcirculation. The hydrogel possessed a typical polyHIPE hierarchical microstructure with interconnected porous morphologies, high porosity, high specific surface area, excellent mechanical properties and suitable swelling properties. Meanwhile, the p(MMA-co-AM)/PVA@PSO hydrogel showed high drug-loading performance and effective PSO release. In addition, both in vitro and in vivo studies showed that the p(MMA-co-AM)/PVA@PSO hydrogel had good biocompatibility and significantly accelerated diabetic wound healing by inhibiting excessive MMP-9 in diabetic wounds, increasing growth factor secretion, improving vascularization, increasing collagen deposition and promoting re-epithelialization. Therefore, this study provided a reliable therapeutic strategy for diabetic wound healing, some theoretical basis and new insights for the rational design and preparation of wound hydrogel dressings with high porosity, high drug-loading performance and excellent mechanical properties.

Serotonin transporter knockdown relieves depression-like behavior and ethanol-induced CPP in mice after chronic social defeat stress.

Patients with stress-triggered major depression disorders (MDD) can often seek comfort or temporary relief through alcohol consumption, as they may turn to it as a means of self-medication or coping with overwhelming emotions. The use of alcohol as a coping mechanism for stressful events can escalate, fostering a cycle where the temporary relief it provides from depression can deepen into alcohol dependence, exacerbating both conditions. Although, the specific mechanisms involved in stress-triggered alcohol dependence and MDD comorbidities are not well understood, a large body of literature suggests that the serotonin transporter (SERT) plays a critical role in these abnormalities. To further investigate this hypothesis, we used a lentiviral-mediated knockdown approach to examine the role of hippocampal SERT knockdown in social defeat stress-elicited depression like behavior and ethanol-induced place preference (CPP). The results showed that social defeat stress-pro depressant effects were reversed following SERT knockdown demonstrated by increased sucrose preference, shorter latency to feed in the novelty suppressed feeding test, and decreased immobility time in the tail suspension and forced swim tests. Moreover, and most importantly, social stress-induced ethanol-CPP acquisition and reinstatement were significantly reduced following hippocampal SERT knockdown using short hairpin RNA shRNA-expressing lentiviral vectors. Finally, we confirmed that SERT hippocampal mRNA expression correlated with measures of depression- and ethanol-related behaviors by Pearson's correlation analysis. Taken together, our data suggest that hippocampal serotoninergic system is involved in social stress-triggered mood disorders as well as in the acquisition and retrieval of ethanol contextual memory and that blockade of this transporter can decrease ethanol rewarding properties.

The other side of the coin: systemic effects of Serendipita indica root colonization on development of sedentary plant-parasitic nematodes in Arabidopsis thaliana.

MAIN CONCLUSION: Upon systemic S. indica colonization in split-root system cyst and root-knot nematodes benefit from endophyte-triggered carbon allocation and altered defense responses what significantly facilitates their development in A. thaliana. Serendipita indica is an endophytic fungus that establishes mutualistic relationships with different plants including Arabidopsis thaliana. It enhances host's growth and resistance to different abiotic and biotic stresses such as infestation by the cyst nematode Heterodera schachtii (CN). In this work, we show that S. indica also triggers similar direct reduction in development of the root-knot nematode Meloidogyne javanica (RKN) in A. thaliana. Further, to mimick the natural situation occurring frequently in soil where roots are unequally colonized by endophytes we used an in vitro split-root system with one half of A. thaliana root inoculated with S. indica and the other half infected with CN or RKN, respectively. Interestingly, in contrast to direct effects, systemic effects led to an increase in number of both nematodes. To elucidate this phenomenon, we focused on sugar metabolism and defense responses in systemic non-colonized roots of plants colonized by S. indica. We analyzed the expression of several SUSs and INVs as well as defense-related genes and measured sugar pools. The results show a significant downregulation of PDF1.2 as well as slightly increased sucrose levels in the non-colonized half of the root in three-chamber dish. Thus, we speculate that, in contrast to direct effects, both nematode species benefit from endophyte-triggered carbon allocation and altered defense responses in the systemic part of the root, which promotes their development. With this work, we highlight the complexity of this multilayered tripartite relationship and deliver new insights into sugar metabolism and plant defense responses during S. indica-nematode-plant interaction.

Overexpression of oilseed rape trehalose-6-phosphate synthesis gene BnaC02.TPS8 confers sensitivity to low nitrogen and high sucrose-induced anthocyanin accumulation in Arabidopsis.

MAIN CONCLUSION: Overexpression of BnaC02.TPS8 increased low N and high sucrose-induced anthocyanin accumulation. Anthocyanin plays a crucial role in safeguarding photosynthetic tissues against high light, UV radiation, and oxidative stress. Their accumulation is triggered by low nitrogen (N) stress and elevated sucrose levels in Arabidopsis. Trehalose-6-phosphate (T6P) serves as a pivotal signaling molecule, sensing sucrose availability, and carbon (C) metabolism. However, the mechanisms governing the regulation of T6P synthase (TPS) genes responsible for anthocyanin accumulation under conditions of low N and high sucrose remain elusive. In a previous study, we demonstrated the positive impact of a cytoplasm-localized class II TPS protein 'BnaC02.TPS8' on photosynthesis and seed yield improvement in Brassica napus. The present research delves into the biological role of BnaC02.TPS8 in response to low N and high sucrose. Ectopic overexpression of BnaC02.TPS8 in Arabidopsis seedlings resulted in elevated shoot T6P levels under N-sufficient conditions, as well as an increased carbon-to-nitrogen (C/N) ratio, sucrose accumulation, and starch storage under low N conditions. Overexpression of BnaC02.TPS8 in Arabidopsis heightened sensitivity to low N stress and high sucrose levels, accompanied by increased anthocyanin accumulation and upregulation of genes involved in flavonoid biosynthesis and regulation. Metabolic profiling revealed increased levels of intermediate products of carbon metabolism, as well as anthocyanin and flavonoid derivatives in BnaC02.TPS8-overexpressing Arabidopsis plants under low N conditions. Furthermore, yeast two-hybrid (Y2H) and bimolecular fluorescence complementation (BiFC) analyses demonstrated that BnaC02.TPS8 interacts with both BnaC08.TPS9 and BnaA01.TPS10. These findings contribute to our understanding of how TPS8-mediated anthocyanin accumulation is modulated under low N and high sucrose conditions.

Conditioned overconsumption is dependent on reinforcer type in lean, but not obese, mice.

Associative learning can drive many different types of behaviors, including food consumption. Previous studies have shown that cues paired with food delivery while mice are hungry will lead to increased consumption in the presence of those cues at later times. We previously showed that overconsumption can be driven in male mice by contextual cues, using chow pellets. Here we extended our findings by examining other parameters that may influence the outcome of context-conditioned overconsumption training. We found that the task worked equally well in males and females, and that palatable substances such as high-fat diet and Ensure chocolate milkshake supported learning and induced overconsumption. Surprisingly, mice did not overconsume when sucrose was used as the reinforcer during training, suggesting that nutritional content is a critical factor. Interestingly, we also observed that diet-induced obese mice did not learn the task. Overall, we find that context-conditioned overconsumption can be studied in lean male and female mice, and with multiple reinforcer types.

Comparative transcriptome analysis identifies candidate genes related to sucrose accumulation in longan (Dimocarpus longan Lour.) pulp.

Sucrose content is one of the important factors to determine longan fruit flavor quality. To gain deep insight of molecular mechanism on sucrose accumulation in longan, we conducted comparative transcriptomic analysis between low sucrose content longan cultivar 'Qingkebaoyuan' and high sucrose content cultivar 'Songfengben'. A total of 12,350 unique differentially expressed genes (DEGs) were detected across various development stages and different varieties, including hexokinase (HK) and sucrose-phosphate synthase (SPS), which are intricately linked to soluble sugar accumulation and metabolism. Weighted gene co-expression network analysis (WGCNA) identified magenta module, including DlSPS gene, was significantly positively correlated with sucrose content. Furthermore, transient expression unveiled DlSPS gene play crucial role in sucrose accumulation. Moreover, 5 transcription factors (MYB, ERF, bHLH, C2H2, and NAC) were potentially involved in DlSPS regulation. Our findings provide clues for sucrose metabolism, and lay the foundation for longan breeding in the future.

Consumption of sucrose in maternal and postnatal stage triggers to kidney affectation in adult male rats.

High sugar-sweetened beverage intake has been related to kidney disease and metabolic alterations in humans. We determine the impact of high sucrose intake from pregnancy until early postnatal days, and during postweaning on kidneys from adult male offspring rats. Wistar female rats were mated and assigned into two groups: one control drinking tap water (CM) and another drinking 5% sucrose diluted in water (SM). At weaning, two offspring per mother were randomly allocated into two experimental groups, one of them had free access to simple water (CO) and the other to 5% sucrose (SO) for 14 weeks. After treatment, levels of relative aquaporin-2 (AQP2), glomerulosclerosis index (GI), collecting tube area, perirenal fat, creatinine and blood ureic nitrogen concentration (BUN) were determined. Two-way ANOVA followed by Bonferroni post-hoc test was used considering P ≤ 0.05 as a significant statistical difference. Sucrose consumption during gestation/lactation and interaction showed an increased AQP2 expression in renal cortex and BUN concentration, while gestation/lactation consumption increased collecting tube area, postweaning consumption increased perirenal fat, and finally, gestation/lactation, postweaning and the interaction causes glomerulosclerosis. Our results suggest that the consumption of sucrose water during gestation/lactation or postweaning or combination triggers pathological changes in the kidney of adult rats.