Liver Glycogen Content Research Articles

The Anti-Fatigue Effect of Glycoprotein from Hairtail Fish (Trichiurus lepturus) on BALB/c Mice

Fatigue is related to a variety of chronic diseases and has become a hot research topic in recent years. Various bioactive components have been extracted from hairtail fish (Trichiurus lepturus); however, none of these studies involved the anti-fatigue activity of hairtail fish glycoprotein (HGP). Thus, antioxidant experiments were conducted in vitro, and the anti-fatigue activity of HGP was further evaluated in BALB/c mice. The effects of HGP on the behavior of BALB/c mice were verified by classical behavioral experiments, and the indicators related to anti-fatigue activity were detected. The results showed that the antioxidant capacity in vitro of HGP increased gradually in the concentration range of 10 to 100 mg/mL. HGP improved the exercise ability of the mice. HGP was also found to significantly (p < 0.05) reduce the serum levels of lactate dehydrogenase (LDH), blood lactic acid (BLA), blood urea nitrogen (BUN), and creatine kinase (CK). The contents of liver glycogen (LG) and muscle glycogen (MG) were also significantly (p < 0.05) increased by HGP. Malondialdehyde (MDA) content in the serum and brains of the mice was significantly (p < 0.05) reduced and catalase (CAT), glutathione peroxidase (GPX), and superoxide dismutase (SOD) were significantly (p < 0.05) increased by HGP, especially in the middle- and high-dose groups. These results enhance our understanding of the anti-fatigue function of HGP and lay an important foundation for the further development and utilization of hairtail fish resources.

Replacing Fish Meal with Hydrolyzed Collagen Derived from Fish By-Products Improved Muscle Quality and Glycolipid Metabolism of Triploid Crucian Carp.

Fish by-products are rich in collagen. Hydrolyzed collagen derived from fish by-products was used to replace fish meal to evaluate the effects on muscle quality and glycolipid metabolism of juvenile triploid crucian carp. A total of 240 juvenile fish with body weight of 10.01 ± 0.02 g were divided into four groups and fed four diets for 66 days: fish meal (FM) replaced with hydrolyzed collagen (HC) in 0% (Control), 2% (2% HC), 4% (4% HC), and 6% (6% HC), respectively. The results were as follows: The increased proportion of fish meal replaced with hydrolyzed collagen linearly and quadratically decreased the specific growth rate (SGR) of triploid crucian carp (p < 0.05). Compared with the control group, the SGR and intestinal α-amylase, trypsin and lipase activities in the 4% and 6% HC groups significantly decreased (p < 0.05), while there was no significant difference between the control and 2% HC groups (p > 0.05). Total umami amino acids content, chewiness and myofiber density of muscle in the 4% and 6% HC groups, as well as the essential fatty acids content in all HC groups increased significantly (p < 0.05). All HC groups significantly increased the serum glutathione peroxidase (GSH-Px) activity and decreased the serum malondialdehyde (MDA) content (p < 0.05). When the replacement amount reached 4%, the serum glucose and liver glycogen content, the liver and serum triglyceride (TG) content, and serum total cholesterol (T-CHO) content were significantly reduced (p < 0.05). In addition, the expression levels of insulin-like growth factor-1 (IGF-1) of the liver in all HC groups and lipolysis-related genes (lipoprotein lipase (LPL), carnitine O-palmitoyltransferase 1 (CPT 1) and hydroxyacyl-coenzyme A dehydrogenase (HADH)) of the liver in the 6% of HC group increased significantly (p < 0.05), and the expression levels of lipogenesis-related genes (fatty acid synthase (FAS) and sterol regulatory element-binding protein 1 (SREBP 1)) of the liver in the 4% HC and 6% HC groups decreased significantly (p < 0.05). In conclusion, the replacement of 2% fish meal with hydrolyzed collagen had no negative effects on the growth of triploid crucian carp, while the replacement of 4% fish meal with hydrolyzed collagen decreased SGR, but improved the muscle quality and decreased glycolipid levels. The maximum proportion of hydrolyzed collagen replacing fish meal should not exceed 4%.

Adult Triploid Rainbow Trout Can Adapt to Various Dietary Lipid Levels by Coordinating Metabolism in Different Tissues.

Triploid rainbow trout can adapt to various dietary lipid levels; however, the mechanisms of systematic adaptation are not well understood. To investigate how adult triploid rainbow trout maintains lipid hemostasis under different exogenous lipid intake, a 77-day feeding trial was conducted. Diets with lipid contents of 20%, 25%, and 30% were formulated and fed to triploid rainbow trout with an initial weight of 3 ± 0.02 kg, and they were named L20, L25, and L30 group, respectively. Results showed that the condition factor, hepatosomatic index, liver color, and plasma triglyceride were comparable among three groups (p > 0.05), whereas the value of specific growth rate, viscerosomatic index, and liver glycogen content gradually increased with increasing dietary lipid level (p < 0.05). A significantly highest value of plasma glucose and nonesterified fatty acids were found in the L30 group (p < 0.05), whereas the significantly higher content of plasma total cholesterol, high-density lipoprotein-cholesterol, and low-density lipoprotein-cholesterol was found in the L25 group compared with those in L20 group (p < 0.05). As for lipid deposition, abdominal adipose tissue, and muscle were the main lipid storage place for triploid rainbow trout when tissues' weight is taken into consideration. Overall quantitative PCR showed that the lipid transport and glycolysis were upregulated, and fatty acids oxidative was downregulated in liver when fish were fed low lipid diets. It meant that the liver was the primary lipid metabolizing organ to low lipid diet feeding, which could switch energy supply between glycolysis and fatty acids oxidation. Fish fed with a moderate dietary lipid level diet could increase lipid uptake and promote lipogenesis in muscle. Abdominal adipose tissue could efficiently uptake excess exogenous free fatty acid through upregulating fatty acid uptake and synthesis de novo and then storing it in the form of triglyceride. Excess lipid uptake is preferentially stored in abdominal adipose tissue through coordinated fatty acid uptake and fatty acid synthesis de novo as dietary lipid levels increased. In summary, triploid rainbow trout can adapt to various dietary lipid levels by coordinating metabolism in different tissues.

Maternal Dietary Carbohydrate Restriction and Mild-to-Moderate Exercise during Pregnancy Modify Aspects of Fetal Development in Rats

To determine whether acute bouts of exercise during pregnancy would predispose the fetus to increased risk if maternal dietary carbohydrate were restricted, untrained pregnant rats were randomly assigned to a 0% (low), 12% (moderate) or 60% (high) glucose diet, and either rested or exercised daily for 20 min from d 16 to term on a rodent treadmill at a mild (15.5 m/min) or moderate (24.3 m/min) intensity. A 3 ՠ3 nested factorial model with and without food intake as a covariate was employed. Both greater exercise intensity and the lower levels of dietary carbohydrate independently decreased term maternal liver and plantaris glycogen concentrations and increased plasma lactate concentrations. However, significant differences due to exercise disappeared (except for plasma lactate) with food intake controlled for in the model, indicating that energy deficits modulated these exercise effects. In contrast, for the offspring, when food intake was controlled for, a restricted level of maternal dietary carbohydrate significantly lowered fetal weight, plasma glucose and insulin concentrations and liver glycogen concentrations measured at term. Exercise alone did not reduce mean fetal weight if nested weights within a litter were used in the statistical analysis. Mild to moderate maternal exercise lowered only fetal plasma glucose concentrations and only if maternal food intake was not controlled for. These results indicate that acute exercise during pregnancy can have detrimental effects on fetal development only if dietary glucose is severely restricted. Otherwise, adequate glucose and energy in the maternal diet in untrained pregnant rats during repeated bouts of acute exercise seem to protect the fetus.

Cinnamaldehyde supplementation acts as an insulin mimetic compound improving glucose metabolism during adolescence, but not during adulthood, in healthy male rats.

Adolescence is a critical period of increased vulnerability to nutritional modifications, and adolescents may respond differently from adults to dietary intake and nutraceuticals. Cinnamaldehyde, a major bioactive compound of cinnamon, improves energy metabolism, as has been shown in studies conducted primarily in adult animals. We hypothesized that cinnamaldehyde treatment may have a higher impact on the glycemic homeostasis of healthy adolescent rats than on healthy adult rats. Male adolescent (30 days) or adult (90 days) Wistar rats received cinnamaldehyde (40 mg/kg) for 28 days by gavage. The oral glucose tolerance test (OGTT), liver glycogen content, serum insulin concentration, serum lipid profile, and hepatic insulin signaling marker expression were evaluated. Cinnamaldehyde-treated adolescent rats showed less weight gain (P = 0.041), improved OGTT (P = 0.004), increased expression of phosphorylated IRS-1 (P = 0.015), and a trend to increase phosphorylated IRS-1 (P = 0.063) in the liver of adolescent rats in the basal state. None of these parameters was modified after treatment with cinnamaldehyde in the adult group. Cumulative food intake, visceral adiposity, liver weight, serum insulin, serum lipid profile, hepatic glycogen content, and liver protein expression of IRβ, phosphorylated IRβ, AKT, phosphorylated AKT, and PTP-1B in the basal state were similar between both age groups. In a healthy metabolic condition, cinnamaldehyde supplementation affects glycemic metabolism in adolescent rats while promoting no changes in adult rats.

Feeding Status Affects Glucose Metabolism in Exercising Horses

Four standardbred horses were used in a Latin square design experiment to evaluate the effects of feeding status on metabolic response to exercise. Horses were deprived of food overnight and then fed 0 (control condition), 1, 2 or 3 kg of corn grain approximately 2.5-3 h before exercise. The exercise test consisted of a warm-up phase (heart rate mean = 144 beats/min) followed by 800 m of walking and then a high intensity work bout for 1600 m (heart rate mean = 206 beats/min). All tests were conducted on a high speed equine treadmill on which the horses had been previously conditioned. During exercise, the control treatment resulted in steady plasma glucose concentrations, whereas all other treatments (1, 2 or 3 kg corn) caused a decline in plasma glucose. Liver glycogen concentration was decreased by exercise in the horses only when they received the control treatment. Plasma lactate concentration was increased by exercise but was not affected by feeding state. Plasma free fatty acid concentrations were highest when the horses received the control treatment. In addition, when horses received the control treatment, plasma free fatty acid concentrations decreased during the warm-up and high intensity phases of the test and increased during the walk phase. Free fatty acid concentrations changed in the horses receiving 1, 2 or 3 kg of corn grain only during the high intensity phase of the exercise test. Feeding status affects the metabolic response of horses to exercise thus further studies are necessary to evaluate the effect of feeding status on exercise performance.

Effects of extruded and pelleted diets with different protein levels on growth performance and nutrient retention of largemouth bass (Micropterus salmoides)

This study investigated effects of extruded diet (ED) and pelleted diet (PD) with differing dietary protein levels on growth performance and nutrient utilization in juvenile largemouth bass (LMB). Nine hundred LMB (initial body weight of 6.47 ± 0.1 g)were fed for eight weeks in five levels of crude protein (40%, 44%, 48%, 52% and 56%) with pelleting or extruding processing technology. The results showed the weight gain (WG, 380.65%), apparent digestibility of crude protein (ADCP, 55.76%), dry matter (DM, 89.70%) and whole-body crude protein (66.32%) of LMB fed with ED52 group were significantly higher than those of other groups (P < 0.05), and FCR (0.96) was lowest. The WGmax was obtained when dietary protein level was 51.6% in ED. Activities of digestive enzymes in liver of LMB fed ED groups were generally higher than those fed PD groups. In addition, lipase, tryptase and α-amylase activities were at higher values between ED48 to ED56. The levels of total cholesterol and triglycerides in serum of LMB were lowest at ED52 group. The liver glycogen content, GLUT1, P-GSK-3β and GYS2 gene expression level in ED groups were significantly higher than those of in PD groups at same protein level (P < 0.05), and the gene expression levels of LMB were lowest in ED52 group. However, the gene expression levels in ED56 group were significantly higher than those of the other groups (P < 0.05). These results indicated that juvenile LMB achieve maximum growth when fed diet for ED at 51.6% protein level.

Whey protein hydrolysate enhances exercise endurance, regulates energy metabolism, and attenuates muscle damage in exercise mice

This study aimed to explore the effects of whey protein concentrate (WPC) and whey protein hydrolysate (WPH) on energy metabolism, muscle injury, and underlying mechanisms in exercise mice by utilizing the swimming 40 min test and exhaustive swimming test, respectively. Results showed that WPH mainly consisted of low molecular weight peptides (359–2266 Da), and 78% of the peptides contained branched chain amino acids. In the swimming 40 min test, WPH possessed better influences than WPC in delaying glycogens consumption, promoting lactate and urea nitrogen elimination, and relieving oxidative stress in mice. Additionally, both WPC and WPH attenuated muscle damage via inhibiting inflammatory response. In the exhaustive swimming test, WPH significantly prolonged swimming time, which was 1.5- and 1.4-fold longer compared with control and WPC groups, respectively. Moreover, WPC and WPH promoted the recovery of muscle damage within 30 min of rest, which might be related to the activation of protein synthesis pathway (mammalian target of rapamycin, mTOR). Notably, compared with WPC, WPH showed better abilities in increasing the contents of glucose and liver glycogen and inhibiting inflammatory pathways, although its swimming time was longer. Taken together, WPH can be an effective ingredient for the prevention and elimination of exercise-induced fatigue.

Active Glycogen Synthase in the Liver Prevents High-Fat Diet-Induced Glucose Intolerance, Decreases Food Intake, and Lowers Body Weight.

Many lines of evidence demonstrate a correlation between liver glycogen content and food intake. We previously demonstrated that mice overexpressing protein targeting to glycogen (PTG) specifically in the liver-which have increased glycogen content in this organ-are protected from high-fat diet (HFD)-induced obesity by reduced food intake. However, the use of PTG to increase liver glycogen implies certain limitations. PTG stimulates glycogen synthesis but also inhibits the enzyme responsible for glycogen degradation. Furthermore, as PTG is a regulatory subunit of protein phosphatase 1 (PP1), which regulates many cellular functions, its overexpression could have side effects beyond the regulation of glycogen metabolism. Therefore, it is necessary to determine whether the direct activation of glycogen synthesis, without affecting its degradation or other cellular functions, has the same effects. To this end, we generated mice overexpressing a non-inactivatable form of glycogen synthase (GS) specifically in the liver (9A-MGSAlb mice). Control and 9a-MGSAlb mice were fed a standard diet (SD) or HFD for 16 weeks. Glucose tolerance and feeding behavior were analyzed. 9A-MGSAlb mice showed an increase in hepatic glycogen in fed and fasting conditions. When fed an HFD, these animals preserved their hepatic energy state, had a reduced food intake, and presented a lower body weight and fat mass than control animals, without changes in energy expenditure. Furthermore, 9A-MGSAlb animals showed improved glucose tolerance when fed an SD or HFD. Moreover, liver triacylglycerol levels that were increased after HFD feeding were lower in these mice. These results confirm that increased liver glycogen stores contribute to decreased appetite and improve glucose tolerance in mice fed an HFD. On the basis of our findings, strategies to preserve hepatic glycogen stores emerge as potential treatments for obesity and hyperglycemia.

Effects of Constant Water Flow on Endurance Swimming and Fatigue Metabolism of Large Yellow Croaker

A trend in large yellow croaker (Larimichthys crocea) aquaculture is to establish production sites suitable for extreme weather conditions. However, continuous and strong currents can harm fish welfare. To determine a suitable site location, the swimming ability of large yellow croakers must be assessed. This study aims to provide novel insights into the physiological characteristics of large yellow croaker swimming and a reference for fishing and cage site selection. Currently, research on large yellow croakers has focused on behavior analysis. Herein, we investigate the effects of swimming on large yellow croakers’ metabolites by examining the preferred speed of the group and the sustained swimming ability of single-tailed fish. We evaluated factors that influence the large yellow croaker’s swimming fatigue by quantifying the metabolite contents and constructing a sustained swimming model. The results showed that large yellow croaker populations tend to grow in low-velocity environments, similar to their traditional habitat. The samples were taken at different swimming times at a flow velocity of 0.35 m/s. According to the results of the metabolite content analysis, blood glucose levels are closely associated with the swimming ability in large yellow croakers. The content of liver glycogen, which regulates blood glucose concentration, decreased in a certain linear relationship. The sustained swimming model of the large yellow croaker was constructed according to the changes in liver glycogen content. Based on our findings, we recommend the following: (1) for large yellow croakers with a size of approximately 13.5 cm (approximately 1 year old), the water velocity inside the cage should not exceed 2.6 BL/s; (2) the concentration of liver glycogen limits the sustained swimming ability of the large yellow croaker, providing a reference for studying the swimming ability of other fish.

Liver glycogen stores via 13C magnetic resonance spectroscopy in healthy children: randomized, controlled study

BackgroundOwing to its role in glucose homeostasis, liver glycogen concentration ([LGly]) can be a marker of altered metabolism seen in disorders that impact the health of children. However, there is a paucity of normative data for this measure in children to allow comparison with patients, and time-course assessment of [LGly] in response to feeding has not been reported. In addition, carbon-13 magnetic resonance spectroscopy (13C-MRS) is used extensively in research to assess liver metabolites in adult health and disease noninvasively, but similar measurements in children are lacking. ObjectivesThe main objectives were to quantify the depletion of [LGly] after overnight fasting and the subsequent response to feeding. MethodsIn a randomly assigned, open-label, incomplete block design study, healthy, normal-weight children (8–12 y) attended 2 evening visits, each separated by ≥5 d and directly followed by a morning visit. An individually tailored, standardized meal was consumed 3-h prior to evening assessments. Participants then remained fasted until the morning visit. [LGly] was assessed once in the fed (20:00) and fasted state (08:00) using 13C-MRS. After the 8:00 assessment, 200 ml of a mixed-macronutrient drink containing 15.5 g (402 kJ) or 31 g carbohydrates (804 kJ), or water only, was consumed, with 13C-MRS measurements then performed hourly for 4 h. Each child was randomly assigned to 2 of 3 drink options across the 2 mornings. Data are expressed as mean (SD). ResultsTwenty-four children including females and males (13F:11M) completed the study [9.9 (1.1) y, BMI percentile 45.7 (25.9)]. [LGly] decreased from 377.9 (141.3) to 277.3 (107.4) mmol/L overnight; depletion rate 0.14 (0.15) mmol/L min. Incremental responses of [LGly] to test drinks differed (P < 0.001), with incremental net area under the curve of [LGly] over 4 h being higher for 15.5 g [−67.1 (205.8) mmol/L·240 min; P < 0.01] and 31 g carbohydrates [101.6 (180.9) mmol/L·240 min; P < 0.005] compared with water [−253.1 (231.2) mmol/L·240 min]. ConclusionsAfter overnight fasting, [LGly] decreased by 22.9 (25.1)%, and [LGly] incremental net area under the curve over 4 h was higher after subsequent consumption of 15.5 g and 31 g carbohydrates, compared to water. Am J Clin Nutr 20XX;xx:xx–xx.

Effects of Carbohydrase Supplementation on Growth Performance, Intestinal Digestive Enzymes and Flora, Glucose Metabolism Enzymes, and glut2 Gene Expression of Hybrid Grouper (Epinephelus fuscoguttatus♀ × E. lanceolatus♂) Fed Different CHO/L Ratio Diets.

An optimal carbohydrate-to-lipid (CHO: L) ratio facilitates fish growth and protein conservation, and carbohydrase promotes nutrient absorption. Therefore, an 8-week feeding trial was conducted to investigate the effects of carbohydrase supplementation on growth performance, intestinal digestive enzymes and flora, glucose metabolism enzymes and glut2 gene expression in juvenile hybrid grouper (Epinephelus fuscoguttatus♀× Epinephelus lanceolatus♂) fed different CHO: L ratios diets. L, M, and H represent CHO:L ratios of 0.91, 1.92 and 3.91, respectively. LE, ME, and HE represent CHO:L ratios of 0.91, 1.92, 3.91, respectively, supplemented with the same ratio of carbohydrase. Results showed that weight gain rate (WGR) and specific growth rate (SGR) reached a maximum in group M and were significantly enhanced by carbohydrase (p < 0.05). Crude lipid content decreased significantly with an increase in the dietary CHO:L ratio (p < 0.05). Significant increases in the trypsin (TRY) and amylase (AMS) activities and significant decreases in the lipase (LPS) activity were observed with increasing dietary CHO:L ratio, and the former two were significantly promoted by carbohydrase (p < 0.05). The content of liver and muscle glycogen increased significantly with the increasing dietary CHO:L ratio but decreased significantly after carbohydrase supplementation (p < 0.05). The glucokinase (GK), pyruvate kinase (PK), Phosphate 6 fructokinase-1 (PFK-1) and phosphoenolpyruvate kinase (PEPCK) activities increased significantly with increasing dietary CHO:L ratio (p < 0.05). Glut2 mRNA expression decreased significantly in liver and increased significantly in intestine with increasing dietary CHO:L ratio (p < 0.05). By linear discriminant analysis (LDA), the abundance of Alistipe was significantly higher in Group ME than in Group M. These results suggested that hybrid grouper can only moderately utilize dietary carbohydrate and lipid in diet, and a certain amount of high glycemic lipids occurred when fed with high-carbohydrate diets. By the weight gain for basis, the supplementation of carbohydrase in Group H with amylase, glycosylase, and pullulanase in a 1:1:1 ratio effectively lowered glycemic lipids, promoted the growth of grouper, digestive enzymes activities and carbohydrate metabolic enzyme, and glut2 gene expression in intestine, effectively balancing the negative effects of high-carbohydrate diet and improving the utilization of carbohydrate.

Changes of Activity of Energy and Ion Exchange Enzymes and the Energy Substrates Content in Tissues of Perca fluviatilis and Rutilus rutilus under Toxic Water Pollution

The paper deals with impact of toxic pollution on activity of energy and ion exchange enzymes in roach and perch. Significant changes in content of energy substrates in liver, gills and muscles of perch and roach were established depending on season and toxic load. The glycogen content in liver of perch specimens from the polluted lake (Kyrilivske) was lower than in specimens from the control lake (Babyne). Also, lower activity of SDH in muscles and gills of roach has been established. It should be noted that roach was characterized by higher variability of the studied enzymes' activity. This indicates the species specificity of the metabolic reactions of the studied fishes to counteract toxic pollution.

Pectin-Based Nanomaterials as a Universal Polymer for Type 2 Diabetes Management

Type 2 diabetes mellitus (T2DM) is characterized by insufficient tissue insulin sensitivity, insufficient compensatory insulin secretory response, and insufficient insulin production by pancreatic islet cells, which account for more than 90% of all instances of diabetes mellitus, and defects in any of the mechanisms at play may cause a metabolic imbalance that results in the development of T2DM. By getting around several delivery limitations, nanomedicine can effectively increase the efficacy of oral drug administration. According to reports, nanostructures are absorbed 15–250 times more readily than microparticles. Furthermore, nanostructures are constantly used to maintain the release of drugs that are encapsulated to lower doses and dosage frequency, improving patient compliance and reducing adverse effects. Pectin is a biocompatible polysaccharide with a natural biological activity, which pectin in rats with type 2 diabetes was discovered to have potent hypoglycemic, antioxidant, immunomodulating, and anticancer properties that improved diabetic conditions and consequences, reduced insulin resistance, improved blood lipid levels, and reduced liver glycogen content, glucose tolerance, and glucose levels. As a result, the purpose of this article was to evaluate the background materials on the current condition of the scientific literature in this field of study and to review the employment feasibility as well as pectin-modified nanomaterial toward T2DM treatment because it has the ability to reduce insulin secretion and/or blood glucose levels following a sugar load.

Combinatory Effect and Modes of Action of Chrysin and Bone Marrow-Derived Mesenchymal Stem Cells on Streptozotocin/Nicotinamide-Induced Diabetic Rats.

The purpose of this study was to see how chrysin and/or bone marrow-derived mesenchymal stem cells (BM-MSCs) affected streptozotocin (STZ)/nicotinamide (NA)-induced diabetic rats as an animal model of type 2 diabetes mellitus (T2DM). Male Wistar rats were given a single intraperitoneal (i.p.) injection of 60 mg STZ/kg bodyweight (bw) 15 min after an i.p. injection of NA (120 mg/kg bw) to induce T2DM. The diabetic rats were given chrysin orally at a dose of 100 mg/kg bw every other day, BM-MSCs intravenously at a dose of 1 × 106 cells/rat/week, and their combination for 30 days after diabetes induction. The rats in the diabetic group displayed impaired oral glucose tolerance and a decrease in liver glycogen content and in serum insulin, C-peptide, and IL-13 levels. They also had significantly upregulated activities in terms of liver glucose-6-phosphatase and glycogen phosphorylase and elevated levels of serum free fatty acids, IL-1β, and TNF-α. In addition, the diabetic rats exhibited a significant elevation in the adipose tissue resistin protein expression level and a significant decrease in the expression of adiponectin, insulin receptor-beta subunit, insulin receptor substrate-1, and insulin receptor substrate-2, which were associated with a decrease in the size of the pancreatic islets and in the number of β-cells and insulin granules in the islets. The treatment of diabetic rats with chrysin and/or BM-MSCs significantly improved the previously deteriorated alterations, with chrysin combined with BM-MSCs being the most effective. Based on these findings, it can be concluded that combining chrysin with BM-MSCs produced greater additive therapeutic value than using them separately in NA/STZ-induced T2DM rats.

Hydroxy-α-sanshool isolated from Zanthoxylum bungeanum Maxim. has antidiabetic effects on high-fat-fed and streptozotocin-treated mice via increasing glycogen synthesis by regulation of PI3K/Akt/GSK-3β/GS signaling.

Type 2 diabetes mellitus (T2DM) is a chronic metabolic disease characterized by hyperglycemia. The fruits of Zanthoxylum bungeanum Maxim. is a common spice and herbal medicine in China, and hydroxy-α-sanshool (HAS) is the most abundant amide in Z. bungeanum and reported to have significant hypoglycemic effects. The purpose of this study was to evaluate the ameliorative effects of HAS on T2DM and the potential mechanisms responsible for those effects. An acute toxicity test revealed the median lethal dose (LD50) of HAS is 73mg/kg. C57BL/6J mice were fed a high-fat diet and given an intraperitoneal injection of streptozotocin (STZ) to induce T2DM in mice to evaluate the hypoglycemic effects of HAS. The results showed that HAS significantly reduced fasting blood glucose, reduced pathological changes in the liver and pancreas, and increased liver glycogen content. In addition, glucosamine (GlcN)-induced HepG2 cells were used to establish an insulin resistance cell model and explore the molecular mechanisms of HAS activity. The results demonstrated that HAS significantly increases glucose uptake and glycogen synthesis in HepG2 cells and activates the PI3K/Akt pathway in GlcN-induced cells, as well as increases GSK-3β phosphorylation, suppresses phosphorylation of glycogen synthase (GS) and increases glycogen synthesis in liver cells. Furthermore, these effects of HAS were blocked by the PI3K inhibitor LY294002. The results of our study suggest that HAS reduces hepatic insulin resistance and increases hepatic glycogen synthesis by activating the PI3K/Akt/GSK-3β/GS signaling pathway.

Anti-hyperglycemic potential and chemical constituents of Aristolochia triangularis Cham. leaves − A medicinal species native to Brazilian forests

Ethnopharmacological relevanceAristolochia triangularis Cham. has been used in Brazilian traditional medicine for various therapeutic purposes, including as a leaf-based infusion for diabetes management. Aim of the study: This study was designed to chemically characterize an infusion of in natura A. triangularis leaves and evaluate the in vivo anti-hyperglycemic properties of this infusion. Materials and methods: Chemical composition was examined using liquid–liquid extraction procedure, chromatographic methods, NMR, and LC−MS/MS. The in vivo anti-hyperglycemic activity of the freeze-dried infusion of A. triangularis leaves (Inf-L-At) was assessed using oral glucose tolerance test (OGTT). Initially, normoglycemic male rats were pre-treated with orally administered Inf-L-At at doses of 62.5, 125, and 250 mg/kg for two consecutive days. On the day of the OGTT, fasting animals received a glucose load (4 g/kg) 30 min after treatment with Inf-L-At, and the blood glucose levels were verified at 15, 30, 60, and 180 min. Intestinal maltase, lactase, and sucrase activities and muscle and liver glycogen contents were also assessed after the OGTT. Results: Inf-L-At extract led to glycemic reduction with no dose-response at 15, 30, and 60 min comparable to that of the antidiabetic drug glibenclamide and was accompanied by an increase in hepatic and muscle glycogen contents. Additionally, there was a significant statistically decrease in the in vitro activity of disaccharidases. Maltase and sucrase activities were inhibited at all doses, whereas lactase activity was inhibited only at 62.5 and 250 mg/kg. In total, 75 compounds were found in the infusion, including seven new ones, (7S*,8S*,7ꞌS*,8ꞌR*)-4,4ꞌ-dihydroxy-3,3ꞌ-dimethoxy-7,9ꞌ-epoxylignan-7ꞌ-ol; 4ꞌ-hydroxy-3ꞌ-methoxy-3,4-methylenedioxy-7,9ꞌ-epoxylignan-9,7ꞌ-diol; triangularisines A, B, and C; N-ethyl-N-methyl-affineine; and N-methyl pachyconfine, and one previously not described as a natural product, epi-secoisolariciresinol monomethyl ether. Conclusion: The results demonstrated the anti-hyperglycemic activity of the infusion from A. triangularis leaves and showed that it is a rich source of lignoids, alkaloids, and glycosylated flavonoids, which are known to exhibit antidiabetic effects and other biological properties that can be beneficial for patients with chronic hyperglycemia, thus certifying the popular use of this herbal drink.

Co-administration of Pterocarpus marsupium Extract and Glibenclamide Exhibits Better Effects in Regulating Hyperglycemia and Associated Changes in Alloxan-induced Diabetic Mice.

Diabetes mellitus (DM) is a well-known global metabolic disorder. For its treatment, glibenclamide (GLB) is very often prescribed. However, herbal drugs are considered effective and better alternatives due to their low risk of side effects. This study was conducted to determine the combined effects of GLB and Pterocarpus marsupium (PM, a commonly available Indian herb) extract for the effective and safe treatment of hyperglycemia in the mouse model. Healthy adult male mice were distributed into five groups (n=7 in each group). Group I acted as the control, whereas groups II, III, IV, and V were considered experimental groups which received a single dosage (150 mg/kg body weight) of alloxan (ALX) intraperitoneally (i.p.). In addition, groups III, IV, and V received a pre-standardized dose of GLB (500 μg/kg body weight), PM extract (150 mg/kg body weight), and GLB+PM, respectively, at the same doses as used in individual treatment, after the seventh day of ALX administration for 15 days and the alterations in different DM related parameters were evaluated. ALX-induced hyperglycemia and other adverse effects were nearly normalized by GLB and PM co-treatment as evidenced by marked suppression in glucose, triglyceride, total-cholesterol, lipid-peroxidation, and lipid-hydroperoxides with an increase in antioxidants status and liver glycogen content. The positive effects were more pronounced when both GLB and PM were given, as compared to that of either of the drugs, administered alone. Liver ultra-structure, analyzed through histology and transmission electron microscopy revealed normalization of the ALX-induced damaged hepatocytes. The presence of epicatechin, the major phytoconstituent of the PM extract, as confirmed by high-performance liquid chromatography (HPLC), is responsible for its antioxidative and glucose-lowering activities. These findings reveal that PM, along with GLB, exhibits synergistic and better effects than the individual drug in regulating hyperglycemia and associated changes in alloxan-induced mice.

High carbohydrate increases amylase, plasma glucose, and gene expression related to glycolysis in giant gourami Osphronemus goramy.

The present study elucidated hepatic molecular and physiological responses of giant gourami to high dietary carbohydrates. Two levels of dietary carbohydrate, normal carbohydrate (34%, NC) and high carbohydrate (53%, HC), were offered to the fish for 60days. We evaluated the expression of genes that are related to carbohydrate metabolism, lipogenic capacities, amino acid catabolism, Krebs cycle, and energy sensing. In addition, we also observed the digestive enzyme activities, plasma glucose, glycogen content, whole-body composition, and growth performance of the fish. On day 30 after treatment, fish fed with high dietary carbohydrate level has significantly higher expression of gck, pk, hk, and ldh than the NC group (P < 0.05). In contrast, fish in the HC group had lower expression of irs1, igf-1, sdh, fbp, g6pc, gyp, and ampk compared to the NC fish (P < 0.05). On day 60 of the feeding trial, gck and hk expressions were still higher in the HC group (P < 0.05), and gyp, gdh, and ampk became increasingly expressed in the HC group. The increase of dietary carbohydrates resulted in significant increases in amylase and protease activity, plasma glucose, liver glycogen, crude protein, and lipid contents of the fish whole-body (P < 0.05). The high carbohydrate feeding reduced the fish growth rate but increased feed efficiency and did not affect mortality. In conclusion, giant gourami could utilize high carbohydrates due to a high amylase secretion, high modulation of carbohydrate metabolism, and large glucose storage capacity.

Effects of different dietary starch sources on growth and glucose metabolism of geese

This experiment investigated the effects of different dietary starch sources on the growth and glucose metabolism of geese. A total of 240 healthy 35-day-old male geese were selected and randomly divided into 4 groups, with 6 replicates per group and 10 geese per replicate. Four types of diets were prepared, with glutinous rice (rapidly-digestible starch), corn, indica rice and high amylose as their starch sources, and fed for 28 d. Results showed that after consuming different feeds, the blood glucose of geese first increased and then decreased, reaching its maximum value 0.5 h after feeding, and there were significant differences between the groups (P < 0.05). The body weight of the corn and indica rice group geese at 63 d was higher than that of the high amylose group (P < 0.05). The serum total cholesterol (TCHO) content in the glutinous rice and corn groups was higher than in the high amylose group (P < 0.05). The serum insulin content in the glutinous rice group was lower than in the corn and high amylose groups (P < 0.05), while the glucagon content was higher (P < 0.05). The α-amylase activities of the pancreas, jejunal chyme, and jejunal mucosa in the glutinous rice group were higher than in the indica rice and high amylose groups (P < 0.05). The liver glycogen content in the glutinous rice group was higher than the other groups (P < 0.05). The liver glucose-6-phosphate dehydrogenase (G-6-PD) content in the glutinous rice group was higher than the high amylose group's (P < 0.05), but the glycogen synthase kinase-3 β (GSK-3β) content was lower (P < 0.05). In conclusion, the corn and indica rice diets had a positive effect on the growth performance of the geese, while the high amylose diet had a negative effect. The glutinous rice diet leads to rapid release of glucose, strengthening glucose metabolism pathways such as glycogen synthesis and the pentose phosphate pathway, and further influencing lipid metabolism.