Liver Glycogen Content Research Articles

Polygonatum cyrtonema Hua polysaccharide exhibits anti-fatigue activity via regulating osteocalcin signaling

In the present study, we explored the anti-fatigue activity and its potential mechanism of a purified Polygonatum cyrtonema polysaccharide (PCP) on mice using weight-loaded swimming test. Results showed that PCP remarkably prolonged the exhaustive swimming time of mice when compared with normal control group. Meanwhile, PCP decreased serum levels of lactic acid (LA), blood uric nitrogen (BUN), superoxide dismutase (SOD), glutathione peroxidase (GSH-Px) and malondialdehyde (MDA), and increased the contents of liver glycogen, muscle glycogen and muscle ATP. These results revealed that PCP had good anti-fatigue ability. The histomorphologic analysis showed that PCP increased the cross-section area of the muscle fibers. Furthermore, PCP significantly enhanced the protein levels of bone morphogenetic protein-2 (BMP-2), phosphor-Smad1, Runt-related transcription factor 2 (Runx2) and osteocalcin (OC) in skeleton. Similar variation was also observed in the expression of osteocalcin signaling mediators of phosphorylated cAMP-response element binding protein (p-CREB) and phosphorylated hormone-sensitive lipase (p-HSL) in skeletal muscle. These results suggested that PCP resisted fatigue possibly via regulating osteocalcin signaling.

Hepatoprotective Effects of Polydatin-Loaded Chitosan Nanoparticles in Diabetic Rats: Modulation of Glucose Metabolism, Oxidative Stress, and Inflammation Biomarkers.

Polydatin (PD) has a broad range of pharmacological activities; however, its effects on diabetic liver damage are poorly studies. This work is aimed to explore possible protective effects of polydatin-loaded chitosan nanoparticles (PD-CSNPs) or PD against liver damage associated with diabetes. Diabetes was induced in rats using nicotinamide/streptozotocin treatment. Diabetic rats were then divided into six groups: normal control rats, diabetic control rats, and rats orally treated with PD, PD-CSNPs, equivalent unloaded CSNPs, or metformin daily for 4 weeks. Treatment with PD and PD-CSNPs significantly reduced the blood glucose content, lipid peroxidation in the liver, and activities of serum transaminases and carbohydrate metabolism enzymes (including succinate dehydrogenase and pyruvate kinase); by contrast, liver glycogen content, glutathione concentration, and activities of the antioxidant enzymes (superoxide dismutase, glutathione peroxidase, catalase, and glucose-6-phosphate dehydrogenase) were markedly increased compared with the control diabetic rats. Furthermore, expression of the tumor necrosis factor α and interleukin-1β mRNAs was significantly downregulated, while expression of glucose transporter 2 and glucokinase mRNAs was strongly upregulated vs. control diabetic rats. We concluded that PD-CSNPs and PD ameliorate diabetic liver damage by modulating glucose transporter 2 expression, affecting the activity of carbohydrate metabolism enzymes, and suppressing oxidative stress and inflammation, PD-CSNPs being more efficient than PD, probably due to higher bioavailability and prolonged release.

Down-regulation of betatrophin enhances insulin sensitivity in type 2 diabetes mellitus through activation of the GSK-3β/PGC-1α signaling pathway.

The incidence of type 2 diabetes mellitus (T2DM) among children and adolescents has been rising. Accumulating evidences have noted the significant role of betatrophin in the regulation of lipid metabolism and glucose homeostasis. In our study, we tried to figure out the underlying mechanism of betatrophin in insulin resistance (IR) in type 2 diabetes mellitus (T2DM). First, fasting serum betatrophin, fasting blood glucose (FBG), insulin, total cholesterol (TC), triglyceride (TG), and low-density lipoprotein cholesterol (LDL-C) were detected in T2DM children. The homeostasis model assessment of insulin resistance (HOMA-IR), Gutt insulin sensitivity index (ISIG) and Matsuda insulin sensitivity index (ISIM) were calculated. A T2DM-IR mouse model was induced by high-fat diet, with the expression of GSK-3β and PGC-1α detected. Besides, HepG2 cells were induced by a high concentration of insulin to establish an IR cell model (HepG2-IR). The cell viability, glucose consumption, liver glycogen content, inflammation, and fluorescence level of GSK-3β and PGC-1α were analyzed. Betatrophin was highly expressed in serum of T2DM children and was positively correlated with FBG, insulin, TC, TG, LDL-C and HOMA-IR, while negatively correlated with ISIG and ISIM. Betatrophin and GSK-3β in the liver tissues of T2DM-IR mice were increased, while the PGC-1α expression was decreased. Betatrophin expression was negatively correlated with PGC-1α and positively correlated with GSK-3β. Silencing of betatrophin enhanced insulin sensitivity through the activation of GSK-3β/PGC-1α signaling pathway. In vitro experiments also found that silencing of betatrophin promoted glucose consumption and glycogen synthesis while inhibited inflammation. Our findings concluded that silencing of betatrophin could enhance insulin sensitivity and improve histopathological morphology through the activation of GSK-3β/PGC-1α signaling pathway.

Antidiabetic effects of fermented milk contained with Gardenia jasminoides water extracts on streptozotocin‐induced mice

Gardenia jasminoides, a kind of flowering plant, possesses numerous bio-activities. The purpose of this study was to investigate the characteristics and hypoglycemic effects of fermented milk (CFM, GFM1, GFM2,and GFM3) contained with 0, 0.1%, 0.2%, and 0.3% of G. jasminoides water extracts. We demonstrated that GFM3 has the highest total count of lactic acid bacteria, water-holding capacity, and antioxidant activities (DPPH, ABTS, and FRAP) among four kinds of fermented milk. In vivo hypoglycemic activity showed that GFM3 notably reduced blood glucose levels, insulin, weight loss rate, food intake, and organ indexes compared with model group. GFM3 could improve the diabetes by reducing the levels of serum TC, TG, LDL-C, and increasing HDL-C content (p < .01). Moreover, it can also increase the levels of hepatic T-SOD, GSH-Px, CAT, hexokinase, and glycogen and decrease MDA content in liver (p < .05 or p < .01). Furthermore, GFM3 stimulated the phosphorylations of p-adenosine 5′-monophosphate-activated protein kinase (AMPK) and Acetyl-CoA carboxylase (ACC), but an inhibitor of Fatty acid synthase (FAS), p < .01. Overall, GFM3 treatment protected the mice better than CFM, so Gardenia jasminoides water extracts is expected to become a hypoglycemic agent. Practical applications With the increasing awareness of nutrition among consumers, the food processing industry is supplementing existing foods, including natural plants or their extracts, to eventually form functional foods. Our results indicated that novel fermented milk contained with Gardenia jasminoides water extracts has better qualities and activities when compared with traditional fermented milk.

Effects of glucose ingestion at different frequencies on glycogen recovery in mice during the early hours post exercise

BackgroundWhen a high-carbohydrate diet is ingested, whether as small frequent snacks or as large meals, there is no difference between the two with respect to post-exercise glycogen storage for a period of 24 h. However, the effect of carbohydrate intake frequency on glycogen recovery a few hours after exercise is not clear. Athletes need to recover glycogen quickly after physical exercise as they sometimes exercise multiple times a day. The aim of this study was to determine the effect of carbohydrate intake at different frequencies on glycogen recovery during the first few hours after exercise.MethodsAfter 120 min of fasting, 6-week-old male ICR mice were subjected to treadmill running exercise (20 m/min for 60 min) to decrease the levels of muscle and liver glycogen. Mice were then given glucose as a bolus (1.2 mg/g of body weight [BW], immediately after exercise) or as a pulse (1.2 mg/g of BW, every 15 min × 4 times). Following this, the blood, tissue, and exhaled gas samples were collected.ResultsIn the bolus group, blood glucose concentration was significantly lower and plasma insulin concentration was significantly higher than those in the pulse group (p < 0.05). The plantaris muscle glycogen concentration in the bolus group was 25.3% higher than that in the pulse group at 60 min after glucose ingestion (p < 0.05). Liver glycogen concentration in the pulse group was significantly higher than that in the bolus group at 120 min after glucose ingestion (p < 0.05).ConclusionsThe present study showed that ingesting a large amount of glucose immediately after exercise increased insulin secretion and enhanced muscle glycogen recovery, whereas frequent and small amounts of glucose intake was shown to enhance liver glycogen recovery.

Effect of Lactobacillus fermentum HFY03 on the Antifatigue and Antioxidation Ability of Running Exhausted Mice.

Yak yogurt is mainly produced in Qinghai-Tibet Plateau. It is a kind of naturally fermented dairy product. It contains abundant microorganisms. Lactobacillus fermentum (LF) HFY03 is a lactic acid bacteria derived from it. Our main research content is to study the influence of LF-HFY03 on the antifatigue and antioxidation ability of running exhausted mice. We gave different doses of LF-HFY03 to mice by gavage for 4 weeks. We selected vitamin C as the positive control group, mainly to study the relationship between antioxidant capacity and fatigue resistance and LF-HFY03 in mice with running exhaustion. The results showed that LF-HFY03 and vitamin C could significantly improve the running time of mice. And with the increase in LF-HFY03 concentration, the exhaustion time of mice was also extended. LF-HFY03 can reduce the content of urea nitrogen and lactic acid and also can increase the content of free fatty acids and liver glycogen. The levels of alanine aminotransferase, serum creatine kinase, and aspartate aminotransferase in mice decreased gradually as the antioxidant peptide level of walnut albumin increased. LF-HFY03 can reduce malondialdehyde (MDA) levels in a quantification-dependent manner and can also increase catalase (CAT) and superoxide dismutase (SOD) levels. LF-HFY03 can also increase the expressions of CAT mRNA, Cu/Zn-SOD, and Mn-SOD in the liver of mice. At the same time, LF-HFY03 can also increase the expression of protein of threonine transporter 1 (AST1)/alanine/cysteine/serine, mRNA, nNOS, and eNOS. At the same time, the solution could reduce the expression of TNF-α, syncytin-1, and inducible nitric oxide synthase (iNOS). The results showed that LF-HFY03 has a high development and application prospect as an antifatigue probiotic nutritional supplement.

Increasing hepatic glycogen moderates the diabetic phenotype in insulin-deficient Akita mice

Hepatic glycogen metabolism is impaired in diabetes. We previously demonstrated that strategies to increase liver glycogen content in a high-fat-diet mouse model of obesity and insulin resistance led to a reduction in food intake and ameliorated obesity and glucose tolerance. These effects were accompanied by a decrease in insulin levels, but whether this decrease contributed to the phenotype observed in this animal was unclear. Here we sought to evaluate this aspect directly, by examining the long-term effects of increasing liver glycogen in an animal model of insulin-deficient and monogenic diabetes, namely the Akita mouse, which is characterized by reduced insulin production. We crossed Akita mice with animals overexpressing protein targeting to glycogen (PTG) in the liver to generate Akita mice with increased liver glycogen content (Akita-PTGOE). Akita-PTGOE animals showed lower glycemia, lower food intake, and decreased water consumption and urine output compared with Akita mice. Furthermore, Akita-PTGOE mice showed a restoration of the hepatic energy state and a normalization of gluconeogenesis and glycolysis back to nondiabetic levels. Moreover, hepatic lipogenesis, which is reduced in Akita mice, was reverted in Akita-PTGOE animals. These results demonstrate that strategies to increase liver glycogen content lead to the long-term reduction of the diabetic phenotype, independently of circulating insulin.

장시간 운동 및 단식이 PPARs isoforms 사이의 단백질 발현에 미치는 효과

PURPOSE: The purpose of this study was to investigate the effect of prolonged exercise and fasting on PPAR isoforms(PPARα & PPARγ1) in rat skeletal muscle.<BR> METHOD: Thirty-six male rats (Sprague-Dawley) were assigned to one of three subgroups: control (n=12), fasted (n=12), exercise (n=12). Rats treated swimming exercise (2hr; 30 min × 4) and fasting (18hr). We measured PPAR isoforms content(PPARα & PPARγ1), liver glycogen, glucose, FFA concentration. All data are presented as means±SD. Date were analyzed with one-way ANOVA, post hoc analysis was perfo rmed to determine using Tukey’s post hoc test. Singificance was set at P＜.05.<BR> RESULTS: In fasted rats, liver glycogen concentration significantly decreased compared to control (P＜.001) and exercisee (P＜.01). Despite the increases in the FFA level both exercise and fasting, there was no significant changes were detected in PPARα & PPARγ1 protein content in soleus muscle (P＞.05).<BR> CONCLUSIONS: Collectively, these results indicate that PPARα & PPARγ1 protein unaffected by both exercise and fasting and/or elevated in FFA concentration. Further studies are required to determine intert issue communication during combined fasting and exercise.

Risk assessment of malathion on health indicators of catfish: Food and water security prospective research

Specimens of Heteropneustes fossilis were treated with various levels of malathion and its 96 h LC50 value was determined. The effects of sub-lethal concentrations of insecticide on hematological and biochemical profile of Heteropneustes fossilis were also registered. The 96 h LC50 value obtained was 8.81 mg/l. Exposure of sub-lethal doses (0.44, 0.88 and 1.76 mg/l which are 5, 10 and 20% of the LC50) of malathion to Heteropneustes fossilis for 3 weeks demonstrated that the toxicant had a detrimental effect on the blood profile of fish. Blood cell (Erythrocyte and leucocytes) counts (from 1.66 to 1.44 cell × 106 × mm3 and 37.93 to 30.24 cell × 103 × mm3; respectively), haemoglobin (Hb) level (from 6.21 to 3.54 g/dl) and haematocrit (Ht) estimates (from 34.26 to 30.52%) were reduced in the fishes exposed to malathion. Elevated level (from 46.25 to 92.45 mg/100 ml) of glucose and decreased quantity (29.95 to 24.25 g/dl) of protein in plasma was registered. Glycogen content in muscle and liver was also decreased. The activity of enzymes glutamic-oxaloacetic transaminase (GOT) and glutamic-pyruvic transaminase (GPT) were high in the fish treated with pesticide. The possible causes for variations in the different parameters were identified and discussed.

Evaluation of anti-diabetic activity of Trianthema portulacastrum Linn in Dithizone induced diabetes in Wistar rats

Trianthema portulacastrum Linn. Whole plant is an extensively used plant for medication in India for the treatment of various health issues. This study was focused to prefigure the antidiabetic potency of Chloroform extract of the Trianthema portulacastrum (CETP) whole plant administered at two doses (100mg/kg and 200 mg/kg) for the duration of 21days in Dithizone - induced diabetic rats. The rats were separated into five groups, each group containing six animals. All Groups except Group I were made diabetic by intraperitonial administration of Dithizone(50mg/kg). Group I served as control group, Group II served as diabetic control received Dithizone(50mg/kg), Group III rats were administered with glibenclamide (10mg/kg), a standard oral hypoglycemic agent while Group IV and Group V diabetic rats were served with 100 mg/kg and 200 mg/kg of CETP whole plant respectively. Potency of the plant extract as an antidiabetic was assessed in dithizone induced diabetic models by comparing biochemical parameters like blood glucose level, Glucose tolerance, lipid profiles along with the liver antioxidant enzymes, glycogen content and Glycogenic enzymes which were quantified using standard experimental procedures. There exists a significant reduction in levels of blood glucose, raise in glucose tolerance, and improved imbalance in lipid metabolism in diabetic rats after administration of the extract at 100mg/kg and 200mg/kg. T.portulacastrum with 200mg/kg of the extract showed the best hypoglycemic action by comparing favorably well with Glibenclamide. This investigation clearly showed that, the extract is endowed with hypoglycemic activity, T.portulacastrum may also defend the deterioration of liver due to diabetes.

Prenatal and post-hatch assessment of two strains of broiler chickens reared under high natural ambient temperatures

Pre-natal (PN) and post-hatch (PH) assessments were carried out on two broiler chicken strains to examine possible origin of strain differences and response to heat stress. One hundred and forty fertile eggs incubated for 18 days as PN and 192 day-old broiler chicks as PH; were evenly divided between two strains (Arbor Acres [AA] and Marshal [MS]). For the PN assessment (day 18, 19 and 21 of incubation), embryos were dissected and organs weighed. Liver glycogen and moisture content of the carcass and residual yolk sac were also determined. Post hatch, average body weight (ABW), average daily feed intake (ADFI) and feed conversion ratio (FCR) were measured under high natural ambient temperatures. At d 18 of incubation, proportional breast weight and yolk moisture was higher in AA than MS (P &lt; 0.05), with the same trend observed at d 21 for yolk weight (%). Breast, gizzard, heart and liver weights were observed to increase linearly, in proportion to weight of embryo (P &lt;0.001), between d 18 and 21 on incubation, while the inverse was observed for yolk weight (%). Post-hatch, ADFI and FCR at the end of the starter phase were lower in MS compared with AA (P &lt; 0.05). However, at the end of the finisher phase, only ADFI was significantly influenced by strain of broiler (AA &lt; MS; P &lt; 0.05). Serum electrolytes and carcass characteristics did not differ between strains (P &gt; 0.05). Phenotype differences in were manifested prior to hatch, with Marshall exhibiting advantage to Arbor Acres under high ambient temperatures.

Musa paradisiaca L. leaf and fruit peel hydroethanolic extracts improved the lipid profile, glycemic index and oxidative stress in nicotinamide/streptozotocin‐induced diabetic rats

This study aimed to assess antihyperlipidemic, cardiac and antioxidant effects as well as mode of actions of Musa paradisiaca (M. paradisiaca) leaf and fruit peel hydroethanolic extracts in nicotinamide (NA)/streptozotocin (STZ)‐induced diabetic rats. Experimental diabetes mellitus was induced by a single intraperitoneal injection of STZ (60 mg/kg body weight), 15 min after intraperitoneal injection of NA (120 mg/kg body weight). NA/STZ‐induced diabetic rats were orally supplemented with M. paradisiaca leaf and fruit peel hydroethanolic extracts in a dose of 100 mg/kg body weight/day for 28 days. The treatment of NA/STZ‐induced diabetic rats with M. paradisiaca leaf and fruit peel extracts significantly decreased the elevated fasting and post‐prandial serum glucose, total cholesterol, triglycerides, LDL‐cholesterol and vLDL‐cholesterol levels and significantly increased the lowered serum insulin level, liver glycogen content, serum HDL‐cholesterol level, homeostasis model assessment‐insulin resistance (HOMA‐IS) and HOMA‐β cell function. The elevated cardiovascular risk indices in diabetic rats were significantly improved due to treatment with M. paradisiaca extracts. Concomitant with the increase in liver glycogen content, the glucose‐6‐phosphatase activity significantly decreased reflecting the decrease in hepatic glucose output. The heart function was potentially ameliorated as manifested by decrease in the elevated serum creatine kinase‐MB, lactate dehydrogenase and aspartate aminotransferase activities after treatments of diabetic rats with M. paradisiaca extracts. The elevated liver lipid peroxidation and the decline in liver glutathione content and superoxide dismutase, glutathione peroxidase and glutathione‐S‐transferase activities were significantly reversed by treatments. Thus, it can be concluded that M. paradisiaca leaf and fruit peel hydroethanolic extracts may have antihyperlipidemic and cardioprotective potentials in NA/STZ‐induced diabetic rats. These effects may be mediated via improvements in the glycemic state, β‐cell function, tissue insulin sensitivity, and antioxidant defense mechanism.

Effect of lemon peel flavonoids on anti-fatigue and anti-oxidation capacities of exhaustive exercise mice

In this study, lemon peel flavonoids (LPF) were administered to investigate its effect on the anti-fatigue and antioxidant capacity of mice that undergo exercise until exhaustion. LPF (88.36 min in LPFH group mice) significantly increased the exhaustion swimming time compare to the untreated mice (40.36 min), increased the liver glycogen and free fatty acid content in mice and reduce lactic acid and BUN content in a dose-dependent manner. As the concentration of lemon peel flavonoids increased, the serum creatine kinase, aspartate aminotransferase, and alanine aminotransferase levels of mice gradually decreased. LPF increases superoxide dismutase (SOD) and catalase (CAT) levels in mice and reduces malondialdehyde levels in a dose-dependent manner. And LPF raises hepatic tissue SOD, CAT activities and reduces skeletal muscle tissue iNOS, TNF-α levels of mice compared to the control group. LPF also enhanced the expression of copper/zinc-superoxide dismutase (Cu/Zn-SOD), manganese-superoxide dismutase (Mn-SOD), and CAT mRNA in mouse liver tissue. LPF also enhanced the expression of alanine/serine/cysteine/threonine transporter 1 (ASCT1) mRNA and attenuate the expression of syncytin-1, inducible nitric oxide synthase (iNOS), and tumor necrosis factor (TNF)-α in mouse skeletal muscle. According to high-performance liquid chromatography (HPLC) analysis, it was found that LPF contains flavonoids such as rutin, astragalin, isomangiferin, naringin, and quercetin. Our experimental data show that LPF has good anti-fatigue effects and anti-oxidation ability. In summary, LPF has high prospects to be developed and added to nutritional supplements.

Chorionic somatomammotropin RNA interference alters fetal liver glucose utilization.

Chorionic somatomammotropin (CSH) is a placenta-specific hormone associated with fetal growth, and fetal and maternal metabolism in both humans and sheep. We hypothesized that CSH deficiency could impact sheep fetal liver glucose utilization. To generate CSH-deficient pregnancies, day 9 hatched blastocysts were infected with lentiviral particles expressing CSH-specific shRNA (RNAi) or scramble control shRNA (SC) and transferred to synchronized recipients. CSH RNAi generated two distinct phenotypes at 135 days of gestational age (dGA); pregnancies with IUGR (RNAi-IUGR) or with normal fetal weight (RNAi-NW). Fetal body, fetal liver and placental weights were reduced (P < 0.05) only in RNAi-IUGR pregnancies compared to SC. Umbilical artery plasma insulin and insulin-like growth factor 1 (IGF1) concentrations were decreased, whereas insulin receptor beta (INSR) concentration in fetal liver was increased (P < 0.05) in both RNAi phenotypes. The mRNA concentrations of IGF1, IGF2, IGF binding protein 2 (IGFBP2) and IGFBP3 were decreased (P < 0.05) in fetal livers from both RNAi phenotypes. Fetal liver glycogen concentration and glycogen synthase 1 (GYS1) concentration were increased (P < 0.05), whereas fetal liver phosphorylated-GYS (inactive GYS) concentration was reduced (P < 0.05) in both RNAi phenotypes. Lactate dehydrogenase B (LDHB) concentration was increased (P < 0.05) and IGF2 concentration was decreased (P < 0.05) in RNAi-IUGR fetal livers only. Our findings suggest that fetal liver glucose utilization is impacted by CSH RNAi, independent of IUGR, and is likely tied to enhanced fetal liver insulin sensitivity in both RNAi phenotypes. Determining the physiological ramifications of both phenotypes, may help to differentiate direct effect of CSH deficiency or its indirect effect through IUGR.

In Vitro and In Vivo Effects of Fermented Oyster-Derived Lactate on Exercise Endurance Indicators in Mice.

Exogenous lactate administration has more recently been investigated for its various prophylactic effects. Lactate derived from potential functional foods, such as fermented oyster extract (FO), may emerge as a practical and effective method of consuming exogenous lactate. The current study endeavored to ascertain whether the lactate derived from FO may act on muscle cell biology, and to what extent this may translate into physical fitness improvements. We examined the effects of FO in vitro and in vivo, on mouse C2C12 cells and exercise performance indicators in mice, respectively. In vitro, biochemical analysis was carried out to determine the effects of FO on lactate content and muscle cell energy metabolism, including adenosine triphosphate (ATP) activity. Western blot analysis was also utilized to measure the protein expression of total adenosine monophosphate-activated protein kinase (AMPK), p-AMPK (Thr172), lactate dehydrogenase (LDH), succinate dehydrogenase (SDHA) and peroxisome proliferator-activated receptor gamma coactivator-1α (PGC-1α) in response to FO administration. Three experimental groups were formed: a positive control (PC) treated with 1% horse serum, FO10 treated with 10 μg/mL and FO50 treated with 50 μg/mL. In vivo, the effects of FO supplementation on exercise endurance were measured using the Rota-rod test, and Western blot analysis measured myosin heavy-chain 2 (MYH2) to assess skeletal muscle growth, alongside p-AMPK, total-AMPK, PGC-1α, cytochrome C and UCP3 protein expression. Biochemical analysis was also performed on muscle tissue to measure the changes in concentration of liver lactate, lactate dehydrogenase (LDH), glycogen and citrate. Five groups (n = 10/per group) consisted of a control group (CON), exercise group (Ex), positive control treated with Ex and 500 mg/kg Taurine (Ex-Tau), Ex and 100 mg/kg FO supplementation (Ex-FO100) and Ex and 200 mg/kg FO supplementation (Ex-FO200) orally administered over the 4-week experimental period.FO50 significantly increased PGC-1α expression (p < 0.001), whereas both FO10 and FO50 increased the expression of p-AMPK (p < 0.001), in C2C12 muscle cells, showing increased signaling important for mitochondrial metabolism and biogenesis. Muscle lactate levels were also significantly increased following FO10 (p < 0.05) and FO50 (p < 0.001). In vivo, muscle protein expression of p-AMPK (p < 0.05) and PGC-1α were increased, corroborating our in vitro results. Cytochrome C also significantly increased following FO200 intake. These results suggest that the effects of FO supplementation may manifest in a dose-response manner. FO administration, in vitro, and supplementation, in vivo, both demonstrate a potential for improvements in mitochondrial metabolism and biogenesis, and even for potentiating the adaptive effects of endurance exercise. Mechanistically, lactate may be an important molecule in explaining the aforementioned positive effects of FO.

Influence of methoxylation on the anti-diabetic activity of ρ-hydroxybenzaldehyde in type 2 diabetic rat model

The present study was designed to investigate the role of methoxylation on the anti-diabetic potential of ρ-hydroxybenzaldehyde (ρ-BN) and its derivatives vanillin (VN) and syringaldehyde (SN) in type 2 diabetes (T2D). Fructose-fed streptozotocin-induced T2D rat model was used and orally treated with 50 and 100 mg/kg body weight of ρ-BN, VN and SN for 28 days. From the results, the diabetic control (DBC) group showed significant (p < 0.05) elevation in insulin resistance, blood glucose, fructosamine, glycogen phosphorylase (GP) activity, lipid profiles, and a significant (p < 0.05) decrease in β-cell functions, insulin, liver glycogen contents, and glycogen synthase (GS) activity. The insulin receptor substrate-1 (IRS-1) and glucose transporter-4 (GLUT-4) mRNA expression in the hepatocyte and skeletal muscle were decreased in DBC group compared to the normal control (NC) group. Oral treatment of the compounds improved the above diabetes-induced alterations to near normal and were comparable to the metformin treated group. Variation in methoxylation of ρ-BN, VN, and SN displayed an inconsistent pattern on the measured indices of diabetes (insulin resistance, β-cell functions, blood glucose, insulin, fructosamine, GS, GP, lipid profiles, IRS-1 and GLUT-4). However, in the case of oral glucose tolerance ability, serum insulin and fructosamine levels, liver glycogen contents and cardiovascular risk indices, the methoxylation mediated positive effects. The phenolic aldehydes (ρ-BN, VN, and SN) possessed anti-T2D activity while methoxylation partly influenced the anti-diabetic effects of the phenolic aldehyde skeleton.

Dietary protein source and protein/carbohydrate ratio affects appetite regulation-related genes expression in gilthead seabream (Sparus aurata)

This study aimed to evaluate the effect of dietary protein source (fishmeal, FM; or plant-feedstuffs, PF) and dietary protein/carbohydrate (P/CH) ratio on gilthead seabream appetite regulation and intermediary metabolism. Additionally, the effect of sampling 5 h after feeding (AF) compared to 24 h AF was also evaluated. Four isolipidic diets were formulated having as major protein sources FM or PF (20% FM and 80% PF), and P/CH ratios of 50/10 or 40/20, being the pregelatinized maize starch the main carbohydrate source (diets FM-P50/CH10; FM-P40/CH20; PF-P50/CH10; PF-P40/CH20). Diets were fed until satiation to 140 g gilthead seabream for 41 days. The expression of appetite regulation genes was assessed at 5 and 24 h AF, while other evaluated parameters were assessed only at 5 h AF. Liver leptin expression was higher at 5 h AF, and brain leptin receptor (lepr) expression was higher at 24 h AF. Brain expression of cocaine- and amphetamine-regulated transcript (cart), leptin and ghrelin receptor (ghrr)-a and liver ghrr-b were also affected by sampling time, but the effects were dependent of the diet provided. FM-based diets promoted the expression of brain cart and leptin (at 24 h AF), and liver growth hormone receptor (ghr)-ii, and increased plasma cholesterol and total lipids levels. Fish fed the PF-based diets had higher liver glycogen content, number and size of adipocytes, and expression of hepatic leptin (at 24 h AF), fatty acid synthase, glucokinase, and target of rapamycin. Regarding dietary P/CH ratio, fish fed the P50/CH10 diets presented higher feed efficiency, plasma triglycerides, and expression of intestine cholecystokinin (at 5 h AF), liver ghrr-b (at 24 h AF), glutamate dehydrogenase and ghr-ii. The protein efficiency ratio, hepatosomatic and visceral indices, plasmatic glucose level, and brain lepr expression (at 5 h AF) were higher in fish fed the P40/CH20 diets. The majority of appetite regulation related-genes were not affected by the use of PF-based diets, while the higher dietary CH seemed to lead to a shorter satiety sensation. PF-based diets promoted liver lipid deposition, hypocholesterolemia, and the activation of glycogenesis pathway, while higher CH content induced an increase in plasma glucose that appeared to be stored as lipids. In conclusion, PF-based diets with up to 20% of CH can be used in gilthead seabream without compromising growth performance and FI, and only slightly modifying appetite and metabolic parameters.

Evaluation of efficacy of Bombax ceiba extract and its major constituent, mangiferin in streptozotocin (STZ)-induced diabetic rats.

Based on the ethno-medicinal use of Bombax ceiba leaf, in the treatment of diabetes, the present study is aimed at evaluation of antidiabetic potential of leaf extract and its major constituent mangiferin. Efficacy of hydroalcoholic extract of Bombax ceiba leaf (BCL, 200 and 400mg/kg body wt.) and mangiferin (MF, 20mg/kg body wt) was studied in streptozotocin (STZ)-induced diabetic rats and associated complications visually, retinopathy, cardiopathy and nephropathy. After 20days, serum glucose, lipid profiles, glycol-hemoglobin % (HbA1c%), liver enzymes activity and glycogen content, and histopathology of the pancreas were corroborated. The study was coxswained for development of validated RP-HPLC method for the estimation of MF in BCL. The results demonstrated significant reductions in the levels of glucose (p<0.001), glycated hemoglobin (HbA1c%, p<0.001), cholesterol, triglycerides and low-density lipoproteins, and concurrent elevation of high density lipoproteins level in the groups administered BCL and MF relative to the controls. It significantly reversed most of the altered metabolic and oxidative stress parameters and histopathological changes. Mangiferin content in BCL was found to be 0.04%w/w. The anti-diabetic effects of BCL may be attributed to its ability to enhance insulin release, antioxidant and hypolipidemic potential.

Water Extract of Potentilla discolor Bunge Improves Hepatic Glucose Homeostasis by Regulating Gluconeogenesis and Glycogen Synthesis in High-Fat Diet and Streptozotocin-Induced Type 2 Diabetic Mice.

Potentilla discolor Bunge, as a traditional Chinese medicine, exhibits many phytochemical activities. The aim of the present study was to investigate the effects of Potentilla discolor Bunge water extract (PDBW) and its underlying mechanisms on gluconeogenesis and glycogen synthesis in high-fat diet/streptozotocin (HFD/STZ)-induced type 2 diabetic mice. LC-MS/MS analyses of PDBW identified 6 major compounds including apigenin-7-O-β-D-glucoside, epicatechin, quercetin 3-O-β-D-glucuronide, kaempferol-3-O-β-D-glucopyranoside, scutellarin, and quercitrin. In the study, a mouse model of type 2 diabetes was induced by 4-week HFD combined with STZ (40 mg/kg body weight) for 5 days. After oral administration of PDBW at 400 mg/kg body weight daily for 8 weeks, the mice with type 2 diabetes showed significant decrease in the levels of fasting blood glucose and glycated hemoglobin A1c (HbA1c), and increase in the insulin level. PDBW improved the glucose tolerance, insulin sensitivity and lipid profiles. Furthermore, PDBW inhibited the mRNA levels of key gluconeogenic enzymes [phosphoenolpyruvate carboxykinase (PEPCK) and glucose-6-phosphatase (G6Pase)] in liver. PDBW also promoted glycogen synthesis by raising the liver glycogen content, decreasing the phosphorylation of glycogen synthase (GS) and increasing the phosphorylation of glycogen synthase kinase3β (GSK3β). Besides, PDBW induced the activation of protein kinase B (Akt) and AMP-activated protein kinase (AMPK), which might explain changes in the phosphorylation of above enzymes. In summary, PDBW supplementation ameliorates metabolic disorders in a HFD/STZ diabetic mouse model, suggesting the potential application of PDBW in prevention and amelioration of type 2 diabetes.

Cloning of the gene encoding acyl-CoA thioesterase 11 and its functional characterization in hybrid yellow catfish (Pelteobagrus fulvidraco ♀ × Pelteobagrus vachelli ♂) under heat stress.

Members of the ACOT (acyl-CoA thioesterase) family hydrolyze fatty acyl-CoA to form free fatty acids (FFAs) and coenzyme A (CoA). These enzymes play important roles in fatty acid metabolism. Here, we report the cloning and functional analysis of acot11β in hybrid yellow catfish (Pelteobagrus fulvidraco ♀×P. vachelli ♂). The open reading frame of acot11β was found to be 594 bp in length, encoding 198 amino acids. We determined the transcript levels of acot11β in ten tissues of hybrid yellow catfish by qRT-PCR and found that it was highly expressed in the liver, so we chose the liver for further analysis. We determined the transcript levels of acot11β in hybrid yellow catfish under heat stress conditions, and analyzed the changes in serum biochemical parameters, liver biochemical parameters, and transcript levels of lipid metabolism-related genes. Healthy yellow catfish were subjected to heat stress at 35°C for 96h, and the experimental results were compared with those from fish in a control group (28°C). The levels of glucose (GLU), total cholesterol (TC), and triglyceride (TG) in serum were significantly increased in the heat-stressed group compared with the control group (P<0.05). Acute heat stress led to decreased liver glycogen contents, but significantly increased TC and TG contents in the liver (P<0.05). The transcript levels of acot11β, acc, and fas were significantly reduced, while that of pparα was significantly increased in hybrid yellow catfish exposed to heat stress (P<0.05). Our results indicate that acot11β plays an important role in regulating lipid metabolism in hybrid yellow catfish, and this metabolic process is greatly affected by temperature. These results may be useful for developing effective strategies to prevent or reduce metabolic disorders of yellow catfish caused by high temperature.