Inhibitory Effects of Siegesbeckia orientalis Extracts on Advanced Glycation End Product Formation and Key Enzymes Related to Metabolic Syndrome

Abstract

Metabolic syndrome typically includes Type 2 diabetes associated with hyperglycemia, central obesity, dyslipidemia and hypertension. It is highly related to oxidative stress, formation of advanced glycated end products (AGEs) and key enzymes, such as carbohydrate digesting enzymes like pancreatic α-amylase and intestinal α-glucosidase, pancreatic lipase and angiotensin I-converting enzyme (ACE). This study used an in vitro approach to assess the potential of four extracts of Siegesbeckia orientalis linne on key enzymes relevant to metabolic syndrome. In this research, S. orientailis was firstly extracted by ethanol. The ethanol extract (SE) was then partitioned sequentially with hexane, ethyl acetate and methanol, and these extracts were named SE-Hex, SE-EA and SE-MeOH, respectively. The experimental results showed that SE-EA had the highest total phenolic content (TPC, 76.9 ± 1.8 mg/g) and the total flavonoids content (TFC, 5.3 ± 0.3 mg/g). This extract exhibited the most significant antioxidant activities, including DPPH radical-scavenging capacity (IC50 = 161.8 ± 2.4 μg/mL), ABTS radical-scavenging capacity (IC50 = 13.9 ± 1.5 μg/mL) and reducing power. For anti-glycation activities, SE-EA showed the best results in the inhibition of AGEs, as well as inhibitory activities against α-glucosidase (IC50 = 362.3 ± 9.2 μg/mL) and α-amylase (IC50 = 119.0 ± 17.7 μg/mL). For anti-obesity activities, SE-EA indicated the highest suppression effect on pancreatic lipase (IC50 = 3.67 ± 0.52 mg/mL). Finally, for anti-hypertension activity, SE-EA also demonstrated the strongest inhibitory activity on ACE (IC50 = 626.6 ± 15.0 μg/mL). Close relationships were observed among the parameters of TPC, antioxidant activities, inhibitory activities on α-amylase, α-glucosidase, lipase and ACE (R > 0.9). Moderate correlations were found among the parameters of TFC, antioxidant activities, and suppression of dicarbonyl compounds formation (R = 0.5–0.9). Taken together these in vitro studies reveal the therapeutic potential of SE-EA extract in the prevention and treatment of metabolic disorders.

Antidiabetic activity of aqueous extract of Sigesbeckia orientalis (St. Paul’s Wort) in alloxan-induced diabetes model

“…Auto-oxidation of glucose in hyperglycemic state can lead to lipid peroxidation, altered antioxidant defense mechanisms leading to further dysfunctions in glucose metabolism and are known to be mediated by reactive oxygen species (ROS) (Chaudhry et al, 2016). In vitro antioxidant and anti-glycation activities of Siegesbeckia orientalis has recently been reported (Hung et al, 2017). Moreover, flavonoids have been shown to produce their antidiabetic effects through enhancement of insulin secretion via regeneration of pancreatic β-cells, enhancement of insulin mediated glucose uptake by target cells, inhibition of aldose reductase and increased uptake of Ca 2+ respectively (Marella, 2017).…”

Phenolic compounds and bioactivity evaluation of aqueous and methanol extracts ofAllium mongolicumRegel

“…Metabolic syndrome, a cluster of some metabolic disorder, including insulin resistance, dyslipidemia, hyperglycemia and hypertension (Huang, 2009). It is suggested that metabolic syndrome is an early pathological features of chronic disease like type 2 diabetes, which is characterized by increase of glucose levels following food intake (Hung et al, 2017). The inhibitory effects on key enzymes related to carbohydrate hydrolyzes, which located in the small intestine, were thought to be an effective strategy to control the condition of postprandial hyperglycemia (Subramanian, Asmawi, & Sadikun, 2008;Tucci, Boyland, & Halford, 2010).…”

Gender-Specific Independent and Combined Effects of the Progesterone and 17-Hydroxyprogesterone on Metabolic Syndrome: From the Henan Rural Cohort Study

“…Sophie et al 20 found increased P4 metabolism in omental adipose tissue of women characterized by abdominal obesity, and they also found that P4 has an inverse association with WC in men. 21 As a critical contributor of MetS, 22 if there is a strong association between obesity and P4, we can infer that there is also an association between MetS and P4. Consistent with the present study, the results of their studies may speculate that the positive relationship between P4 and MetS in women.…”