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Schisandrins are a group of chemical components, contained in Schisandra chinensis , determined as lignans. They involve: schisandrin A, B, C and schisandrol A. Those substances, which are well-known in traditional Chinese medicine, are hepatoprotective, anti-inflammatory, antioxidative and antineoplastic. Furthermore, there is a wide array of trials and analyses performed on animal models, which makes us presume that after running trials on a human model, schisandrins will be used as sport supplements. Those components stimulate skeletal muscles hypertrophy; there is a proved impact on soleus and gastrocnemius muscles, as well as the protective and regenerative role. Lignans decrease triglycerides and total cholesterol levels, leading to body mass reduction. They are also hypoglycemic, facilitate the transport and metabolism of glucose as GLUT-2 activators or adiponectin antagonists. They enhance the sensitivity to insulin, lowering the levels of interleukin 1, interleukin 2 and interleukin 6. The components have also nephroprotective activity in hyperglycemic states, arresting the progression of the disorder. Schisandrins influence the endocrine system, decreasing cortisol level and slightly increasing testosterone level. In our review we juxtapose the trials, emphasizing the schisandrins impact on the efficiency of human body. Effects of use of schisandrins are very promising, however, there is still not enough of good evidences to use these substances without any doubts. There are also reports of interactions with CYP3A4 or induction of hypertriglyceridemia. [ABSTRACT FROM AUTHOR]

Islet-Neogenesis Associated Protein-Pentadecapeptide (INGAP-PP) increases β-cell mass and enhances glucose and amino acids-induced insulin secretion. Our aim was to demonstrate its effect on liver metabolism. For that purpose, adult male Wistar rats were injected twice-daily (10 days) with saline solution or INGAP-PP (250 μg). Thereafter, serum glucose, triglyceride and insulin levels were measured and homeostasis model assessment (HOMA-IR) and hepatic insulin sensitivity (HIS) were determined. Liver glucokinase and glucose-6-phosphatase (G-6-Pase) expression and activity, phosphoenolpyruvate carboxykinase (PEPCK) expression, phosphofructokinase-2 (PFK-2) protein content, P-Akt/Akt and glycogen synthase kinase-3β (P-GSK3/GSK3) protein ratios and glycogen deposit were also determined. Additionally, glucokinase activity and G-6-Pase and PEPCK gene expression were also determined in isolated hepatocytes from normal rats incubated with INGAP-PP (5 μg/ml). INGAP-PP administration did not modify any of the serum parameters tested but significantly increased activity of liver glucokinase and the protein level of its cytosolic activator, PFK-2. Conversely, INGAP-PP treated rats decreased gene expression and enzyme activity of gluconeogenic enzymes, G-6-Pase and PEPCK. They also showed a higher glycogen deposit and P-GSK3/GSK3 and P-Akt/Akt ratio. In isolated hepatocytes, INGAP-PP increased GK activity and decreased G-6-Pase and PEPCK expression. These results demonstrate a direct effect of INGAP-PP on the liver acting through P-Akt signaling pathway. INGAP-PP enhances liver glucose metabolism and deposit and reduces its production/output, thereby contributing to maintain normal glucose homeostasis. These results reinforce the concept that INGAP-PP might become a useful tool to treat people with impaired islet/liver glucose metabolism as it occurs in T2D. [ABSTRACT FROM AUTHOR]

Abstract: Litopenaeus vannamei were reared in close cycle over seven generations and tested for their capacity to digest starch and to metabolise glucose at different stages of the moulting cycle. After acclimation with 42.3% of carbohydrates (HCBH) or 2.3% carbohydrates (LCBH) diets and at high salinity (40 g kg−1) or low salinity (15 g kg−1), shrimp were sampled and hepatopancreas (HP) were stored. Total soluble protein in HP was affected by the interaction between salinity and moult stages (p<0.05). Specific activity of α-amylase ranged from 44 to 241 U mg protein−1 and a significant interaction between salinity and moult stages was observed (p<0.05), resulting in highest values at stage C for low salinity (mean value 196.4 U mg protein−1), and at D0 in high salinity (mean value 175.7 U mg protein−1). Specific activity of α-glucosidase ranged between 0.09 and 0.63 U mg protein−1, an interaction between dietary CBH and salinity was observed for the α-glucosidase (p<0.05) and highest mean value was found in low salinity–LCBH diet treatment (0.329 U mg protein−1). Hexokinase specific activity (range 9–113 mU mg protein−1) showed no significant differences when measured at 5 mM glucose (p>0.05). Total hexokinase specific activity (range 17–215 mU mg protein−1) showed a significant interaction between dietary CBH and salinity (p<0.05) with highest value (mean value 78.5 mU mg protein−1) found in HCBH–high salinity treatment, whereas in the other treatments the activity was not significantly different (mean value 35.93 mU mg protein−1). A synergistic effect of dietary CBH, salinity and moult stages over hexokinase IV-like specific activity was also observed (p<0.05). As result of this interaction, the highest value (135.5±81 mU mg protein−1) was observed in HCBH, high salinity at D0 moult stage. Digestive enzymes activity is enhanced in the presence of high starch diet (HCBH) and hexokinase can be induced at certain moulting stages under the influence of blood glucose level. Perspectives are opened to add more carbohydrates in a growing diet, exemplifying the potential approach for less-polluting feed. [Copyright &y& Elsevier]