In Vitro and in Vivo Anti-Hyperglycemic Effects of Omija (Schizandra chinensis) Fruit

Abstract

The entrocytes of the small intestine can only absorb monosaccharides such as glucose and fructose from our diet. The intestinal absorption of dietary carbohydrates such as maltose and sucrose is carried out by a group of α-glucosidases. Inhibition of these enzymes can significantly decrease the postprandial increase of blood glucose level after a mixed carbohydrate diet. Therefore, the inhibitory activity of Omija (Schizandra chinensis) extract against rat intestinal α-glucosidase and porcine pancreatic α-amylase were investigated in vitro and in vivo. The in vitro inhibitory activities of water extract of Omija pulp/skin (OPE) on α-glucosidase and α-amylase were potent when compared to Omija seeds extract (OSE). The postprandial blood glucose lowering effect of Omija extracts was compared to a known type 2 diabetes drug (Acarbose), a strong α-glucosidase inhibitor in the Sprague-Dawley (SD) rat model. In rats fed on sucrose, OPE significantly reduced the blood glucose increase after sucrose loading. Furthermore, the oxygen radical absorbance capacity (ORAC) of OSE and OPE was evaluated. OPE had higher peroxyl radical absorbing activity than OSE. These results suggest that Omija, which has high ORAC value with α-glucosidase inhibitory activity and blood glucose lowering effect, could be physiologically useful for treatment of diabetes, although clinical trials are needed.

Stimulation of Phenolics, Antioxidant and α-Glucosidase Inhibitory Activities During Barley (Hordeum vulgare L.) Seed Germination

“…Rat intestinal α-glucosidase assay was described previously in the method of Cho et al [18] with slight modification. A total of 3 g of rat-intestinal acetone powder was suspended in 9 mL of 0.9 % saline, and the suspension was vortex 12 times for 30 s at 4°C.…”

Antidiabetic effects of natural plant extracts via inhibition of carbohydrate hydrolysis enzymes with emphasis on pancreatic alpha amylase

“…Several in vivo experiments have demonstrated the anti-hyperglycemic or hypoglycemic effects of different natural plant extracts that acted through various mechanisms (132,(146)(147)(148). Specific studies carried out in animal models have supported the hypothesis that pancreatic alpha-amylase enzyme inhibition of plant extracts might be the most promising mechanism for the observed antidiabetic effect.…”

“…Fruits and leaves of Schizandra chinensis (Schisandraceae) contain high levels of anthocyanins, which could be related with its favorable health properties (131). Thus, when water extracts of Omija pulp/skin and seed extracts were evaluated against PPA activity, both extracts were able to inhibit the enzyme (74% and 2%, respectively) at a concentration of 1mg/ml (132).…”

Cyanobacterial Pigments as Natural Anti-Hyperglycemic Agents: An In vitro Study

“…For example, Schizandra chinensis is a type of berry consumed widely in Korea and its fruits and seeds have been used as traditional medicines in different parts of Asia. However, the pulp extract of this berry was found to inhibit α-amylase effectively whereas the seed extract did not show any significant activity (Jo et al, 2011). However, they were able to effectively inhibit the action of α-glucosidase in vitro even at lower concentrations.…”

“…Acute liver toxicity leading to hepatitis has also been widely reported in various studies (Acarbose, US National Library of Medicine, 2016). Alternate remedies in such cases can include fruits such as berries (Jo et al, 2011), tea and tea pomace extracts (Oh et al, 2015), plant extracts (Zia-Ul-Haq et al, 2011), pine bark (Kim et al, 2004), green tea extracts (Gao et al, 2013), herbal medicines such as Tinospora cordifolia (Sengupta et al, 2009), and vegetables such as bitter gourd (Ahmad et al, 2012).…”