High-sugar Feeding Research Articles

The Effects of Long-Term High Fat and/or High Sugar Feeding on Sources of Postprandial Hepatic Glycogen and Triglyceride Synthesis in Mice.

In MASLD (formerly called NAFLD) mouse models, oversupply of dietary fat and sugar is more lipogenic than either nutrient alone. Fatty acids suppress de novo lipogenesis (DNL) from sugars, while DNL inhibits fatty acid oxidation. How such factors interact to impact hepatic triglyceride levels are incompletely understood. Using deuterated water, we measured DNL in mice fed 18-weeks with standard chow (SC), SC supplemented with 55/45-fructose/glucose in the drinking water at 30% (w/v) (HS), high-fat chow (HF), and HF with HS supplementation (HFHS). Liver glycogen levels and its sources were also measured. For HS and HFHS mice, pentose phosphate (PP) fluxes and fructose contributions to DNL and glycogen were measured using [U-13C]fructose. The lipogenic diets caused significantly higher liver triglyceride levels compared to SC. DNL rates were suppressed in HF compared to SC and were partially restored in HFHS but supplied a minority of the additional triglyceride in HFHS compared to HF. Fructose contributed a significantly greater fraction of newly synthesized saturated fatty acids compared to oleic acid in both HS and HFHS. Glycogen levels were not different between diets, but significant differences in Direct and Indirect pathway contributions to glycogen synthesis were found. PP fluxes were similar in HS and HFHS mice and were insufficient to account for DNL reducing equivalents. Despite amplifying the lipogenic effects of fat, the fact that sugar-activated DNL per se barely contributes suggests that its role is likely more relevant in the inhibition of fatty acid oxidation. Fructose promotes lipogenesis of saturated over unsaturated fatty acids and contributes to maintenance of glycogen levels. PP fluxes associated with sugar conversion to fat account for a minor fraction of DNL reducing equivalents.

Mechanism of Yupingfeng Powder on hepatic insulin resistance in type 2 diabetes mellitus rats by regulating IRS/PI3K/Akt pathway

Based on the insulin receptor substrate(IRS)/phosphoinositide 3-kinase(PI3K)/protein kinase B(Akt) pathway, the intervention effect of Yupingfeng Powder on type 2 diabetes mellitus(T2DM) rats was studied, and the potential mechanism of improving T2DM hepatic insulin resistance was explored. A T2DM rat model was established by feeding with high-fat and high-sugar feed combined with intraperitoneal injection of streptozotocin. Successfully modeled rats were selected and divided into a model group, a positive control group(MET), and a Yupingfeng Powder group. At the same time, a blank group was set up, and corresponding drugs were given by gavage. The model group and blank group were given an equal amount of physiological saline by gavage. During the experiment, body mass and fasting blood glucose were regularly measured, and glucose tolerance and insulin tolerance were measured at the end of the experiment. After the experiment, the levels of blood glucose, insulin, blood lipids, and related liver function indicators were measured; changes in liver pathological damage were observed, levels of liver monoamine oxidase were detected, and qRT-PCR was used to detect mRNA expression levels of IRS/PI3K/Akt pathway related genes. Compared with the model group, the Yupingfeng Powder group had an increase in body weight, a decrease in fasting blood glucose, fasting insulin, and steady-state model evaluation index, a decrease in the area under the curve of glucose tolerance and insulin tolerance tests, a decrease in serum total cholesterol, triglycerides, and low-density lipoprotein cholesterol content, and an increase in high-density lipoprotein cholesterol content. Compared with the model group, the Yupingfeng Powder group showed a decrease in liver monoamine oxidase levels, a decrease in serum aspartate aminotransferase, alanine aminotransferase, alkaline phosphatase, and total bilirubin levels, and an increase in total protein and albumin levels. Hematoxylin-eosin(HE) staining showed a reduction in pathological liver cell damage. Compared with the model group, the Yupingfeng Powder group showed a significant increase in the mRNA expression levels of IRS1, PI3K, and Akt in the liver of rats, as well as a significant decrease in the mRNA expression levels of interleukin-6(IL-6) and tumor necrosis factor-α(TNF-α). This indicates that Yupingfeng Powder can regulate the IRS/PI3K/Akt signaling pathway and glucose and lipid metabolism disorders, increase insulin sensitivity, improve hepatic insulin resistance, and thus play a therapeutic role in T2DM.

The genetic and dietary landscape of the muscle insulin signalling network.

Metabolic disease is caused by a combination of genetic and environmental factors, yet few studies have examined how these factors influence signal transduction, a key mediator of metabolism. Using mass spectrometry-based phosphoproteomics, we quantified 23,126 phosphosites in skeletal muscle of five genetically distinct mouse strains in two dietary environments, with and without acute in vivo insulin stimulation. Almost half of the insulin-regulated phosphoproteome was modified by genetic background on an ordinary diet, and high-fat high-sugar feeding affected insulin signalling in a strain-dependent manner. Our data revealed coregulated subnetworks within the insulin signalling pathway, expanding our understanding of the pathway's organisation. Furthermore, associating diverse signalling responses with insulin-stimulated glucose uptake uncovered regulators of muscle insulin responsiveness, including the regulatory phosphosite S469 on Pfkfb2, a key activator of glycolysis. Finally, we confirmed the role of glycolysis in modulating insulin action in insulin resistance. Our results underscore the significance of genetics in shaping global signalling responses and their adaptability to environmental changes, emphasising the utility of studying biological diversity with phosphoproteomics to discover key regulatory mechanisms of complex traits.

The genetic and dietary landscape of the muscle insulin signalling network

Metabolic disease is caused by a combination of genetic and environmental factors, yet few studies have examined how these factors influence signal transduction, a key mediator of metabolism. Using mass spectrometry-based phosphoproteomics, we quantified 23,126 phosphosites in skeletal muscle of five genetically distinct mouse strains in two dietary environments, with and without acute in vivo insulin stimulation. Almost half of the insulin-regulated phosphoproteome was modified by genetic background on an ordinary diet, and high-fat high-sugar feeding affected insulin signalling in a strain-dependent manner. Our data revealed coregulated subnetworks within the insulin signalling pathway, expanding our understanding of the pathway’s organisation. Furthermore, associating diverse signalling responses with insulin-stimulated glucose uptake uncovered regulators of muscle insulin responsiveness, including the regulatory phosphosite S469 on Pfkfb2, a key activator of glycolysis. Finally, we confirmed the role of glycolysis in modulating insulin action in insulin resistance. Our results underscore the significance of genetics in shaping global signalling responses and their adaptability to environmental changes, emphasising the utility of studying biological diversity with phosphoproteomics to discover key regulatory mechanisms of complex traits.

Regulation of sirt1 and foxO1 in glucose metabolism of Megalobrama amblycephala

Both silent information regulator 2 homolog 1 (sirt1) and forkhead box transcription factor 1 (foxO1) are crucial transcription factors involved in glucolipid metabolism and energy regulation. The presnt study aimed to understand their regulatory roles in glucose metabolism. Molecular cloning and sequencing of sirt1 gene of Megalobrama amblycephala (masirt1) was conducted and cellular localization of both the factors were analysed. Their effects and action patterns in the glucose metabolism of Megalobrama amblycephala (M. amblycephala) were investigated through acute and long-term glucose tolerance assays. The results revealed that the full-length masirt1 cDNA sequence was 2350 bp and closely related to Sinocyclocheilus rhinocerous. Sirt1 and foxO1 were found to be mutually dependent and localized in the nucleus. Acute glucose tolerance tests revealed that the expression levels of both factors in the liver of M. amblycephala showed an initial increase followed by a decrease. Plasma glucose levels in M. amblycephala significantly increased at 2 and 12 h (P < 0.05). In a long-term breeding experiment with high-sugar feeding, the expressions of the sirt1 and foxO1 genes in the kidney and intestine of M. amblycephala exhibited synergistic changes. The 51WS groups had significantly higher levels of sirt1 and foxO1 gene expression in the kidney and intestine compared to the 0WS and 17WS groups (P < 0.05). Overall, masirt1 is evolutionarily highly conserved, and the interaction site of sirt1 and foxO1 is located in the nucleus. In long-term hyperglycemic regulation, sirt1 and foxO1 exhibit synergistic regulatory effects in the kidney and intestine of M. amblycephala. This study provides insights into how sirt1 and foxO1 regulate glucose metabolism in M. amblycephala.

Angelica polysaccharides relieve blood glucose levels in diabetic KKAy mice possibly by modulating gut microbiota: an integrated gut microbiota and metabolism analysis

BackgroundAngelica polysaccharides (AP) have numerous benefits in relieving type 2 diabetes (T2D). However, the underlying mechanisms have yet to be fully understood. Recent many reports have suggested that altering gut microbiota can have adverse effects on the host metabolism and contribute to the development of T2D. Here, we successfully established the T2D model using the male KKAy mice with high-fat and high-sugar feed. Meanwhile, the male C57BL/6 mice were fed with a normal feed. T2D KKAy mice were fed either with or without AP supplementation. In each group, we measured the mice's fasting blood glucose, weight, and fasting serum insulin levels. We collected the cecum content of mice, the gut microbiota was analyzed by targeted full-length 16S rRNA metagenomic sequencing and metabolites were analyzed by untargeted-metabolomics.ResultsWe found AP effectively alleviated glycemic disorders of T2D KKAy mice, with the changes in gut microbiota composition and function. Many bacteria species and metabolites were markedly changed in T2D KKAy mice and reversed by AP. Additionally, 16 altered metabolic pathways affected by AP were figured out by combining metagenomic pathway enrichment analysis and metabolic pathway enrichment analysis. The key metabolites in 16 metabolic pathways were significantly associated with the gut microbial alteration. Together, our findings showed that AP supplementation could attenuate the diabetic phenotype. Significant gut microbiota and gut metabolite changes were observed in the T2D KKAy mice and AP intervention.ConclusionsAdministration of AP has been shown to improve the composition of intestinal microbiota in T2D KKAy mice, thus providing further evidence for the potential therapeutic application of AP in the treatment of T2D.

Rapamycin Suppresses Penile NADPH Oxidase Activity to Preserve Erectile Function in Mice Fed a Western Style High‐Fat, High‐Sucrose Diet

IntroductionThe mechanistic target of rapamycin (mTOR) is a nutrient‐sensitive cellular signaling kinase that has been shown to be activated by high‐fat and/or high‐sugar feeding in highly metabolic tissues such as adipose tissue, liver, and skeletal muscle. mTOR activation has been implicated in the excess production of reactive oxygen species (ROS) resulting from overnutrition, which has been associated with activation of NADPH oxidase (Nox) as a source of excess ROS production. A Western style high‐fat, high‐sucrose diet has recently been used to induce erectile dysfunction (ED) in rodents, in which elevated Nox has been implicated in ED pathogenesis. The objective of this study was to determine if mTOR is an upstream mediator of Nox in the penis in response to the Western diet (WD) and to determine if this pathway is relevant in WD‐induced ED.MethodsYoung male C57Bl/6 mice (n = 90) were fed a control diet (CD) or WD ad libitum for 12 weeks. For the final four weeks of the dietary intervention, mice were intraperitoneally injected with either vehicle (Veh) or the mTOR inhibitor rapamycin (Rap; 2 mg/kg) three days/week. Following the intervention, erectile function was assessed by measuring intracavernosal pressure (ICP) and mean arterial pressure (MAP) during cavernous nerve stimulation. In separate mice following the same intervention, in vivo ROS production was measured in the penis utilizing a microdialysis approach. Microdialysis probes were inserted into the penis of anesthetized mice and perfused with saline containing 100 μM Amplex Ultrared, 1 U/ml horseradish peroxidase, and 10 U/ml superoxide dismutase, and fluorescence was measured from three dialysate replicates. 300 μM apocynin, a Nox inhibitor, was then added to the perfusate, and additional dialysate samples were analyzed. Nox‐mediated ROS were determined by calculation of the ROS that was inhibited by apocynin. Western blots were performed on corpus cavernosum (CC) tissue for Nox subunits, phosphorylation of the mTOR active site, and phosphorylation of p70S6K, a downstream mediator of mTOR Complex 1 (mTORC1) signaling. Significant differences between groups were determined by two‐way ANOVA with Tukey’s multiple comparisons post‐hoc analysis.ResultsErectile function was significantly impaired in mice fed the WD in the vehicle condition, while Rap restored erectile function in the WD condition. P‐mTOR/mTOR and P‐p70S6K/p70S6K were increased in CC from WD‐Veh relative to CD‐Veh mice, while both of these measures were markedly suppressed by Rap treatment regardless of diet. Penile production of the ROS hydrogen peroxide and superoxide were elevated in vehicle treated WD‐fed mice, which was normalized in WD‐fed mice with Rap treatment. Similarly, Nox‐mediated penile ROS was elevated in vehicle treated WD‐fed mice, which was normalized in WD‐fed mice with Rap treatment. The Nox subunits Nox2, p47, and p22 were significantly elevated in CC from WD‐Veh mice, while Rap significantly blunted these expressions. The p67 and Nox4 subunits were not different amongst any groups.ConclusionsThe mTORC1/p70S6K axis appears to be an upstream mediator of Nox2 in the corpus cavernosum in response to chronic consumption of a high‐fat, high‐sucrose, Western pattern diet, which has a deleterious effect on erectile function.

Exploratory Study on Expression of Fatty Tissue in Gestational Diabetes Mouse.

Objective To investigate the changes of UCP1 protein in brown fat by establishing a model of gestational diabetes mellitus through intervention of high fat and carbohydrate diet. To explore the changes of UCP1 protein in brown fat in gestational diabetic mice, and analyze the characteristics of abnormal glucose metabolism in gestational diabetic mice and its relationship with changes in adipocyte morphology and insulin resistance. Methods Eighty C57BL/6J pregnant mice were randomly divided into a normal control group and a high-fat and high-sugar feeding group. The normal control group was fed a normal diet, while the high-fat and high-sugar group was fed a high-fat and high-sugar diet to establish a gestational diabetes mellitus (GDM) model. On the pregnancy days 0, 10, and 18, the weight and fasting glucose were measured. On the pregnancy day 18, the triglycerides (TG), the total cholesterol (TC), free fatty acid (FFA), insulin levels, and insulin resistance index (HOMA-IR) were measured or calculated. At the same time, brown fat UCP1 protein of the two groups of pregnant mice were measured using Western blot Observed the Adipose tissue pathological changes by staining HE. The adipocyte was observed, and the correlation was analyzed. Results Twenty-one pregnant mice reach the level of gestational diabetes diagnosis (FBG ≥ 5.1 mmol/L) in the high-fat and high-sugar diet group. On the pregnancy day 10 and 18, the fasting plasma glucose and the body weight significantly increased (P < 0.05). The total cholesterol, triglycerides, free fatty acid, insulin level, and insulin resistance index of the GDM group were also higher compared with that of the control group (P < 0.05). The adipocyte size significantly increased in the GDM mice. TG, TC, FFA, and body weight at 18 days of gestation were significantly correlated with HOMA-IR and single-adipocyte area in the GDM mice. HOMA-IR was significantly correlated with a single-adipocyte area. Compared with the normal control group, the UCP1 proteins of GDM mice decreased significantly and negatively correlated with body weight increase. Conclusion Feeding C57BL/6J pregnant mice with high fat and high sugar to establish a gestational diabetes mouse model has good stability and is similar to human gestational diabetes. The reduction of brown fat UCP1 protein in GDM mice has a certain correlation with obesity tendency and obvious insulin resistance.

Gut Microbiota and Their Role in Health and Metabolic Disease of Dairy Cow.

Ruminants are mostly herbivorous animals that employ rumen fermentation for the digestion of feed materials, including dairy cows. Ruminants consume plant fibre as their regular diet, but lack the machinery for their digestion. For this reason, ruminants maintain a symbiotic relation with microorganisms that are capable of producing enzymes to degrade plant polymers. Various species of microflora including bacteria, protozoa, fungi, archaea, and bacteriophages are hosted at distinct concentrations for accomplishing complete digestion. The ingested feed is digested at a defined stratum. The polysaccharic plant fibrils are degraded by cellulolytic bacteria, and the substrate formed is acted upon by other bacteria. This sequential degradative mechanism forms the base of complete digestion as well as harvesting energy from the ingested feed. The composition of microbiota readily gets tuned to the changes in the feed habits of the dairy cow. The overall energy production as well as digestion is decided by the intactness of the resident communal flora. Disturbances in the homogeneity gastrointestinal microflora has severe effects on the digestive system and various other organs. This disharmony in communal relationship also causes various metabolic disorders. The dominance of methanogens sometimes lead to bloating, and high sugar feed culminates in ruminal acidosis. Likewise, disruptive microfloral constitution also ignites reticuloperitonitis, ulcers, diarrhoea, etc. The role of symbiotic microflora in the occurrence and progress of a few important metabolic diseases are discussed in this review. Future studies in multiomics provides platform to determine the physiological and phenotypical upgradation of dairy cow for milk production.

New therapeutic targets in lipid lowering: high-sugar feeding in infants, lipoprotein(a), and lipoprotein lipase.

New therapeutic targets in lipid lowering: high-sugar feeding in infants, lipoprotein(a), and lipoprotein lipase.

High-sugar feeding and increasing cholesterol levels in infants.

Hypercholesterolaemia is an important risk factor for cardiovascular disease. Both total and LDL cholesterol levels are three-fold higher at the end of the first year of life and about four-fold higher in adulthood compared with the neonatal period. In the USA, only 25% of infants are exclusively breastfed and simple carbohydrate-rich formulas are preferentially consumed. Spikes in fasting glucose and insulin have been reported in formula-fed infants and are associated with higher levels of proprotein convertase subtilisin/kexin type 9, suggesting a potential link between high simple sugar intake and consequent increase in LDL cholesterol in early childhood.

EFFECTS OF DIET ALTERATIONS, WITH OR WITHOUT FECAL MICROBIAL TRANSPLANTS, ON BONE INTEGRITY

High fat feeding exerts a negative impact on bone quality and strength. Gut microbiota have been strongly linked to bone outcomes in several models, though a clear mechanism linking alterations in gut microbiota, diet composition, and bone has not yet been elucidated. PURPOSE: To determine if alterations in diet, with or without fecal microbial transplants (FMT) can rescue bone integrity in diet-induced obesity. METHODS: 6-wk old male C57Bl/6 mice (n=10/group) were randomized to a low-fat (LF) or high fat, high sugar (HFS) diet ad libitum for 13 wks. HFS mice were randomized to one of three groups for 4 wks: LF diet with FMT from the LF mice (HFS/LF+), LF diet with sham FMT using PBS (HFS/LF), or HFS diet with FMT from the LF mice (HFS/HFS+) to simulate the impact of combined diet alteration and addition of “healthy” microbes, diet alterations only, and addition of “healthy” microbes only, respectively. Animals had free access to a running wheel until terminated at 23 wks of age. Statistical analyses were performed using a two-way ANOVA and Tukey’s post-hoc test. RESULTS: HFS/HFS+ mice showed greater absolute femoral neck (FN) strength versus HFS/LF and HFS/LF+ mice (p<0.003), while LF/LF mice had the greatest relative FN strength versus all groups (p<0.016). Whole femur bone mineral density (BMD, g/cm2) was greater in HFS/HFS+ versus all groups (p<0.023); LF/LF mice had the highest BMD when normalized to body weight (p<0.029). Immunostaining for tumor necrosis factor alpha, sclerostin, insulin-like growth factor 1, and interferon gamma in cortical and cancellous bone revealed no differences between groups. Despite no difference in marrow adipocyte number (#/mm2) between groups, HFS/HFS+ mice had greater marrow adipocyte size (μm2) versus LF/LF mice; diet alteration, with and without transplanted “healthy” microbes, was able to partially attenuate increased marrow adipocyte size. CONCLUSIONS: A change in diet from HFS to LF led to reduced absolute FN strength compared to HFS/HFS+ and LF/LF mice, with no apparent effect from transplanted “healthy” gut microbes. LF/LF mice had greater relative femoral neck strength. Altering diet, with and without FMT’s, was sufficient to partially rescue the detrimental impacts of high fat, high sugar feeding on bone integrity.

Therapeutic effect of dexmedetomidine on myocardial ischemia reperfusion injury in type 2 diabetic rat model under P13K/Akt pathway

This research aims to study the therapeutic effect of dexmedetomidine on type 2 diabetic rats reperfusion injury model. A rat model of type 2 diabetes was induced by high-fat and high-sugar feed, and a reperfusion rat model was obtained by ligating the left anterior descending branch and reperfusion. The diabetic rat model sham operation group was used as the control group (DM-S), the rats were divided into diabetic reperfusion group (DM-IR) and dexmedetomidine treatment group (DM-D), dexmedetomidine combined with DM-DW (DM-DW), and Wortmannin treatment group (DM-W). In this study, the MB isoenzyme of creatine kinase (CK-MB) concentration was determined by ELISA competition method, superoxide dismutase (SOD) activity in rat plasma was detected by superoxide dismutase WST-1, and the content of malonaldehyde (MDA) in rat plasma was determined by thiobarbituric acid method. Besides, Western Blot was used to detect the expression changes of Akt, P-Akt, GSK-3β, and P-GSK-3β in rat myocardial tissue. The results showed that the content of CK-MB and SOD in DM-D group was significantly higher than that in DM-IR group (P < 0.05), and the content of MAD was significantly lower than that in DM-IR group (P < 0.05). The content of CK-MB and SOD in DM-DW group and DM-W group were significantly higher than that in DM-D group (P < 0.05), and the content of MDA was significantly lower than that in DM-D group (P < 0.05). However, expression of p-Akt and p-GSK-3β protein in DM-D group was significantly higher than that in DM-DW group and DM-W group (p < 0.05). Accordingly, dexmedetomidine can play a role in treating myocardial ischemia-reperfusion injury in type 2 diabetes by regulating the expression of related genes in the P13K/Akt signaling pathway.

Effects of Compound Centella on Oxidative Stress and Keap1-Nrf2-ARE Pathway Expression in Diabetic Kidney Disease Rats.

The formula of Compound Centella mainly contains 3 traditional Chinese herbs: Centella asiatica (L.) Urb. (JiXueCao), Astragalus Membranaceus Fish. (HuangQi), and Tripterygium wilfordii Hook. f. (LeiGongTeng). Though this formula is effective for treating diabetic kidney disease (DKD) in clinic, the exact mechanism is still unclear. This study aims to investigate the effect and antioxidant mechanism of Compound Centella on DKD rats. High-performance liquid chromatography (HPLC) was applied to analyse 3 herbs in Compound Centella. Sprague-Dawley rats were divided into the normal group (NG), DKD group (DKDG), Compound Centella group (CCG), and losartan group (LG), with 8 rats in each group. On the first day of the experiment, rats in the NG were fed with ordinary –feed, while the other groups were fed with high-fat and high-sugar feed. On the 29th day, except the NG, the other 3 groups received a single intraperitoneal injection of streptozocin (STZ, 35 mg/kg). Fasting blood glucose (FBG) was measured on the 1st day, 32nd day, 46th day, 56th day, 84th day, and 112th day. Total protein/creatinine ratio of urine was determined by the phenol red assay on the 1st day and 112th day. Serum creatinine (Scr) was determined by an automatic biochemical analyser on the 112th day. Kidneys were collected on the 112th day for analysis and evaluation. Periodic acid-Schiff (PAS) staining, hematoxylin-eosin (HE) staining, and transmission electron microscopy were used to observe kidney pathological changes. The mRNA and protein expressions of Kelch-like ECH-associated protein 1 (Keap1) and nuclear factor-erythroid 2-related factor 2 (Nrf2) in renal tissues were detected by RT-qPCR, Western blot, and immunohistochemistry. Oxidative stress was evaluated by detecting the levels of malondialdehyde (MDA) and heme oxidase-1 (HO-1). The results showed that the content of asiaticoside, astragaloside, and triptolide in the herb was 5960, 809, and 2.42 μg/g and in the Compound Centella was 340, 64, and 0.1403 μg/mL by HPLC. Compound Centella reduced the urine protein/creatinine ratio and improved renal pathology in the kidneys of DKD rats. In addition, the mRNA and protein expressions of Keap1 and Nrf2 in kidneys were upregulated by Compound Centella. The expressions of MDA were downregulated but HO-1 were upregulated by Compound Centella. Therefore, the protective effect of Compound Centella in the kidney of DKD rats may be related to regulating the Keap1-Nrf2-ARE pathway under oxidative stress, suggesting Compound Centella as a promising treatment against DKD.

Gross saponin of Tribulus terrestris improves erectile dysfunction in type 2 diabetic rats by repairing the endothelial function of the penile corpus cavernosum.

ObjectiveTo investigate the effect of gross saponins of Tribulus terrestris (GSTT) on erectile function in rats resulting from type 2 diabetes mellitus (T2DMED).MethodsThe T2DMED model was constructed by high-fat and high-sugar feeding and streptozotocin injection. After 4 weeks of GSTT intervention. Intracavernous pressure (ICP) and mean arterial pressure (MAP) were measured in each group. The level of nitric oxide (NO) in the cavernous tissue was detected using the nitrate reductase method. The production of reactive oxygen species (ROS) was detected using DHE fluorescent probe detection. Cyclic adenosine monophosphate (cGMP) level was detected by enzyme-linked immunosorbent assay, and endothelial nitric oxide synthase (eNOS) was detected using immunohistochemistry. Masson staining was used to detect the cavernosal smooth muscle/collagen ratio. Apoptosis in endothelial cells was measured using TUNEL. Western blotting method to detect the protein expression level of eNOS, TIMP-1, cleaved caspase 3, and cleaved caspase 9.ResultsAfter treatment, the ICP and ICP/MAP values of the GSTT were significantly higher than those of the T2DMED group (P<0.05). Unlike the T2DMED group, the GSTT group showed significantly increased NO levels (P<0.05) and decreased ROS levels (P<0.05). There was no significant difference between the GSTT group and the sildenafil group in increasing cGMP levels (P>0.05), and the mixed group had higher levels than these two groups (P<0.05). Immunohistochemistry and Western blotting showed that the expression of eNOS in the GSTT was significantly higher than that in the T2DMED groups (P<0.05). Masson staining showed that the smooth muscle/collagen ratio of the GSTT group was significantly higher than that of the T2DMED groups (P<0.05), the expression of TIMP-1 was lower than that of T2DMED group (P<0.05). TUNEL assay showed that the apoptotic index and cleaved caspase 3 and cleaved caspase 9 expression level of GSTT group were lower than that of the T2DMED group (P<0.05).ConclusionGSTT can protect T2DMED rats’ erectile function by improving penile endothelial function and inhibiting cavernosum fibrosis, inhibiting apoptosis, and is synergistic with sildenafil.

067 Rapamycin Suppresses NADPH Oxidase-mediated Reactive Oxygen Species Production and Reverses Erectile Dysfunction in Western Diet-fed Mice

The mammalian target of rapamycin (mTOR) is a nutrient-sensitive cellular signaling kinase that has been shown to be activated by high-fat and/or high-sugar feeding in highly metabolic tissues such as adipose tissue, liver, and skeletal muscle. mTOR activation has been implicated in the excess production of reactive oxygen species (ROS) resulting from overnutrition, which has been associated with activation of NADPH oxidase (Nox) as a source of excess ROS production. A Western style high-fat, high-sugar diet has recently been used to induce erectile dysfunction (ED) in rodents, in which elevated Nox has been implicated in ED pathogenesis. The objective of this study was to determine if mTOR is an upstream activator of Nox in the penis in response to the Western diet (WD) and to determine if this pathway is relevant in WD-induced ED. Young male C57Bl/6J mice (n = 90) were fed a control diet (CD) or WD ad libitum for 12 weeks. For the final four weeks of the dietary intervention, mice were intraperitoneally injected with either vehicle or the mTOR inhibitor rapamycin (Group 1: 1 mg/kg; Group 2: 2 mg/kg) three days/week. Following the intervention, erectile function was assessed by measuring intracavernosal pressure (ICP) and mean arterial pressure (MAP) during cavernous nerve stimulation. In separate mice following the same intervention, in vivo ROS production was measured in the penis utilizing a microdialysis approach. Microdialysis probes were inserted into the penis of anesthetized mice and perfused with saline containing 100 μM Amplex Ultrared, 1 U/ml horseradish peroxidase, and 10 U/ml superoxide dismutase. ROS convert the reagents to a fluorescent byproduct resorufin, which was measured in the outflowing dialysate. Three replicate samples were collected, after which 300 μM apocynin, a Nox inhibitor, was added to the perfusate, and additional samples were collected. Nox-mediated ROS were determined by calculation of the ROS that was inhibited by apocynin. Significant differences between groups were determined by two-way ANOVA with Tukey’s multiple comparisons post-hoc analysis, with an alpha level of 0.05.

Effects of Scutellaria barbata extracts on serum glycolipid hormones and pancreatic-tissue structure in type 2 diabetic rats

The study describes the effect of Chinese herbal medicine extracts from Scutellaria barbata on serum glycolipid hormones and pancreatic-tissue structure in type 2 diabetes mellitus (T2DM) rats. Healthy Wistar rats (n = 150) were divided randomly into two groups: healthy (30) and model (120). The healthy group was fed normally for 30d and injected citrate buffer on day 31. The model group was fed high-fat and high-sugar feed for 30d and injected STZ on day 31. On day 38 the model group was divided randomly into four groups: model group, low-, medium-, and high-dose S. barbata (n = 30 in each). 5, 10, 20, and 30dafter treatment, serum levels of FGB, INS, CORT, TG, TC, HDL-C, and LDL-C in all groups were measured and pancreatic-tissue sections were stained with hematoxylin–eosin and aldehyde fuchsine to observe the tissue structure. The results showed significantly decreased levels of FGB, INS, CORT, and LDL-C (P less than 0.01) and increased level of HDL-C (P greator than 0.05).In addition, the damaged structure of diabetic pancreatic tissue has been partially restored in the low-dose S. barbata group. These results show that low-dose S. barbata extract treatment is effective in treating T2DM.

Effect of 3:7 ratio of Astragalus total saponins and Curcumin on the diabetic nephropathy rats model.

ObjectiveStudy the effect of the 3:7 ratio of Astragalus total saponins and Curcumin on the model of diabetic nephropathy rats, and explore its mechanisms.MethodsDiabetic nephropathy rats model was established by high-fat and high-sugar feed feeding combined with streptozotocin (STZ) injection in sublingual vein. Measured fasting blood glucose of rats on the 10, 20 and 30th day, and measured urine protein content in urine of rats on 30th days. Two hours after the last administration, measured glycated serum protein (GSP), insulin antibody (IA), triglyceride (TG), total cholesterol (TC), low density lipoprotein (LDL), high density lipoprotein (HDL), malondialdehyde (MDA), insulin, superoxide dismutase (SOD), glutathione (GSH), urea nitrogen (BUN), creatinine (Cr) in the serum and calculated the renal index of rat. Take the viscera of pancreas and kidney, and HE staining, so as to observe pathological changes.ResultAstragalus total saponins and Curcumin 3:7 compatibility each dose group can significantly reduce the diabetic nephropathy rats blood glucose of 30th days, significantly reduce the level of GSP, IA, TG, TC, LDL (P < 0.01), and reduce MDA levels with different degrees (P < 0.01 or P < 0.05), and significantly increase the level of insulin (P < 0.01), increase the level of HDL, SOD and GSH with different degrees (P < 0.01 or P < 0.05 or P > 0.05); Astragalus total saponins and Curcumin 3:7 compatibility each dose group also can decrease renal index, UN, and Cr levels with different degrees and improve the pathological changes of pancreatic tissue and kidney tissue in diabetic nephropathy rats with different degrees (P < 0.01 or P < 0.05 or P > 0.05).ConclusionThe 3:7 ratio of Astragalus total saponins and Curcumin can achieve the treatment and protection effects on diabetic nephropathy rats by improve the glycometableolism, insulin resistance, lipid metableolism, oxidative stress levels, and pathological changes.

A High-Fat High-Sucrose Diet Rapidly Alters Muscle Integrity, Inflammation and Gut Microbiota in Male Rats.

The chronic low-level inflammation associated with obesity is known to deleteriously affect muscle composition. However, the manner in which obesity leads to muscle loss has not been explored in detail or in an integrated manner following a short-term metabolic challenge. In this paper, we evaluated the relationships between compromised muscle integrity, diet, systemic inflammatory mediators, adipose tissue, and gut microbiota in male Sprague-Dawley rats. We show that intramuscular fat, fibrosis, and the number of pro-inflammatory cells increased by 3-days and was sustained across 28-days of high-fat high-sugar feeding compared to control-diet animals. To understand systemic contributors to muscle damage, dynamic changes in gut microbiota and serum inflammatory markers were evaluated. Data from this study links metabolic challenge to persistent compromise in muscle integrity after just 3-days, a finding associated with altered gut microbiota and systemic inflammatory changes. These data contribute to our understanding of early consequences of metabolic challenge on multiple host systems, which are important to understand as obesity treatment options are developed. Therefore, intervention within this early period of metabolic challenge may be critical to mitigate these sustained alterations in muscle integrity.

Antidiabetic and antioxidant effects of catalpol extracted from Rehmannia glutinosa (Di Huang) on rat diabetes induced by streptozotocin and high-fat, high-sugar feed.

BackgroundDiabetes, associated with hyperlipidemia and oxidative stress, would lead to an increased production of reactive oxygen species. Rehmannia glutinosa (Di Huang) is widely used to nourish yin, invigorate the kidney (shen), and treat xiao ke (a diabetes-like syndrome in Chinese medicine). This study aims to investigate the antidiabetic and antioxidant effects of catalpol from R. glutinosa on rat diabetes induced by streptozotocin (STZ) and high-fat, high-sugar feed.MethodsRats (eight rats in each group at least) were induced diabetes by an initial high-fat high-sugar feed for 3 weeks, followed by an intraperitoneal injection of STZ (30 mg/kg) for 3 days, and rats were fasted overnight before treatments. Catalpol at a dose of 0, 5, 10, 20 or 50 mg/kg was administrated through bolus intravenous injection to the experimental rats to find the most effective anti-hyperglycemic dose of catalpol to further study body weight loss, water intake, and food intake. The most effective catalpol dose was given to the diabetic model rats with hyperlipidemia, and the levels of blood sugar, plasma total cholesterol (TC), triglyceride (TG), and high-density lipoprotein cholesterol (HDL-C) were measured after catalpol administration once a day for 2 weeks. An oral glucose challenge test (OGCT) was performed after above experiments in which the most effective dose of catalpol has been determined. Levels of glutathione peroxidase (GSH-PX), catalase (CAT), superoxide dismutase (SOD), and malondialdehyde (MDA) were measured by corresponding reagent kits and morphological changes of the pancreas were observed with histopathological examination using H&E stain.ResultsCatalpol at a dose of 50 mg/kg ameliorated body weight loss and increased water and food intake. Catalpol also attenuated the increase of plasma TC (P = 0.0067) and TG (P = 0.0084) and increased HDL-C (P = 0.0336). The OGCT revealed that catalpol reduced the increase of plasma glucose. The activities of antioxidative enzymes (SOD, P = 0.0037; GSH-PX, P = 0.0066; CAT, P = 0.005) were enhanced and MDA was reduced (P = 0.003). Furthermore, catalpol reduced the morphological impairment of the pancreas.ConclusionCatalpol protected against STZ-induced diabetes with high-fat and high-sugar feed with ameliorated structural impairment of the pancreas and restored balance between oxidative enzymes and antioxidative enzymes.