Isolated flavonoids from Ficus racemosa stem bark possess antidiabetic, hypolipidemic and protective effects in albino Wistar rats.

Ficus racemosa (FR) has been used for thousands of years in Ayurvedic system of medicine in India and is closely associated with prevention, treatment and cure of various human ailments like obesity and diabetes. It is popularly known as gular. A vast and wide range of chemical compounds like polyphenols, friedelane-type triterpenes, norfriedelane type triterpene, eudesmane-type sesquiterpene including various glycosides had been isolated from this plant. However, no detail studies related to isolation of flavonoids has been reported previously with their antidiabetic, hypolipidemic and toxicological consequences. The present study was undertaken to evaluate antidiabetic, hypolipidemic and toxicological assessments of flavonoids isolated from Ficus racemosa (FR) stem bark. We isolated four flavonoids from stem bark of FR and structures were confirmed by Infrared spectroscopy (IR), Nuclear Magnetic Resonance (NMR) (both 1D and 2D), mass spectroscopy (MS). Later, these flavonoids were administered to streptozotocin (STZ) rats once in a day for a period of seven days at 100mg/kg dose. We measured blood glucose level and body weight changes at different days (1st, 3rd, 5th and 7th days). Serum lipid profiles were also estimated to investigate the hypolipidemic potential of flavonoids in the similar experiment. Various oxidative stress parameters in pancreas and liver and hepatic biomarker enzymes in plasma were also determined to investigate the toxicity potential of isolated flavonoids. Finally, we performed docking studies to find out the mechanism of action. Our results collectively suggested that four flavonoids reduced blood glucose level and restored body weight, signifying antidiabetic action. There were reduction of other lipid profile parameters and increase of high density lipoprotein (HDL) during administration of flavonoids, also signifying hypolipidemic action. Various oxidative stress biomarkers and hepatic enzymes levels were also normalized with respect to diabetic control at the same time. Docking studies revealed that isolated flavonoids showed their antidiabetic potential via binding to PPARγ and GLUT1 receptors. The isolated four flavonoids demonstrated good antidiabetic, hypolipidemic and antioxidant properties in STZ diabetic rats which supported the use of FR stem bark as useful supplementary drug for future antidiabetic therapy.

Keshari AK ，Kumar G ，Kushwaha PS ，Bhardwaj M ，Kumar P ，Rawat A ，Kumar D ，Prakash A ，Ghosh B ，Saha S ... -  《-》

Antidiabetic activity of Ficus amplissima Smith. bark extract in streptozotocin induced diabetic rats.

Ficus amplissima commonly known as kal-itchchi have a long history of use in Ayurveda, Siddha and Unani herbal preparations in Indian traditional system of medicine. It has been used in folklore medicine for the treatment of diabetes. The aim of the present study was to evaluate the effect of methanolic extract of the bark of Ficus amplissima (FAB) in streptozotocin-induced diabetic rats. Oral administration of FAB bark at the doses of 50mg/kg, 100mg/kg and 150 mg/kg was studied in normal, glucose-loaded and STZ-induced diabetic rats. The three doses caused significant reduction in blood glucose levels in all the models. The effect was more pronounced in 50mg/kg and 100mg/kg than 150 mg/kg. FAB also showed significant increase in serum insulin and body weight. The glycogen content in liver, skeletal muscle, total protein contents were markedly increased and marker enzymes of hepatic function of STZ-induced diabetic rats while there was significant reduction in the levels of serum triglyceride and total cholesterol. FAB also showed significant anti-lipid peroxidative effect in the pancreas of STZ-induced diabetic rats. The anti-diabetic effect of FAB was compared with glibenclamide, a well known hypoglycemic drug. Histological analysis showed the regenerative effect of FAB on the β-cells of diabetic rats. Results of this experimental study indicated that FAB possessed anti-diabetic and antioxidant activities. Hence it could be used as a natural source of antidiabetic (Type-I) and antioxidant drug.

Arunachalam K ，Parimelazhagan T 《-》

Antidiabetic effects of Morus alba fruit polysaccharides on high-fat diet- and streptozotocin-induced type 2 diabetes in rats.

Type 2 diabetes mellitus (T2DM) is becoming a serious threat to human health. The fruit of Morus alba L. is widely used as a traditional Chinese medicine for the treatment of DM, dizziness, tinnitus, insomnia, and premature graying, as well as to protect the liver and kidneys. Several studies have demonstrated that the aqueous extracts of the roots bark, leaves, and ramuli of mulberry, which are known to contain polyphenols and polysaccharides, have antihyperglycemic and antihyperlipidemic activities. The aim of the present study was to further investigate the active polysaccharides from M. alba fruit by evaluating the antidiabetic activities of different fractions on T2DM rats and elucidate the mechanism underlying these activities. Diabetic rats were treated with two fractions of M. alba fruit polysaccharides (MFP50 and MFP90). The disease models were induced by a high-fat diet and low dose injection of streptozotocin and were compared to normal rats and metformin-treated diabetic rats. After seven weeks, the fasting blood glucose (FBG), oral glucose tolerance test (OGTT), fasting serum insulin (FINS) levels, homeostasis model of assessment-insulin resistance (HOMA-IR), glycated serum protein (GSP), and serum alanine transaminase (ALT) levels, as well as serum lipid profiles and histopathological changes in the pancreas were measured. Next, the expressions of the insulin signaling pathway were measured by western blot analysis to elucidate the potential mechanism underlying these antidiabetic activities. After seven weeks of treatment, a significant reduction in the FBG levels, OGTT-area under the curve (OGTT-AUC), FINS, HOMA-IR, ALT, and triglyceride (TG) values of the MFP50 group was observed. On the other hand, in the MFP90 group, the FBG, OGTT-AUC, FINS, HOMA-IR, GSP, and TG levels were significantly reduced. The level of high-density lipoprotein cholesterol (HDL-c) and the proportion of HDL-c to total cholesterol (TC) significantly increased in the MFP50 group. Moreover, MFP50 and MFP90 induced repair of damaged pancreatic tissues of the diabetic rats. The hypoglycemic effect of MFP50 was more stable than MFP90, whereas the hypolipidemic effect of MFP90 was slightly better than MFP50. Moreover, the expression levels of InsR, IRS-2, Akt and GLUT4 in the MFP90 group significantly increased relative to that of the T2DM group. MFP50 and MFP90 have markedly antihyperglycemic and antihyperlipidemic effects and can clearly relieve diabetes symptoms in the T2DM rat model. The M. alba fruit polysaccharides may potentially be utilized as an effective treatment for T2DM. Further research into the structures of active M. alba fruit polysaccharides and their mechanisms in promoting antidiabetic effects are underway.

Jiao Y ，Wang X ，Jiang X ，Kong F ，Wang S ，Yan C ... -  《-》

Ficus recemosa bark extract attenuates diabetic complications and oxidative stress in STZ-induced diabetic rats.

Joshi H ，Vaishnav D ，Sanghvi G ，Rabadia S ，Airao V ，Sharma T ，Parmar S ，Sheth N ... -  《-》

Antidiabetic effect of total flavonoids from Sanguis draxonis in type 2 diabetic rats.

Sanguis draxonis (SD) is a kind of red resin obtained from the wood of Dracaena cochinchinensis (Lour.) S. C. Chen (Dracaena cochinchinensis). It is a Chinese traditional herb that is prescribed for the handling of diabetic disorders, which is also supported by an array of scientific studies published in recent years. Although chemical constituents of this plant material have also been previously evaluated (Tang et al., 1995; Wei et al., 1998), it still remains poorly understood which constituent is the major contributor to its antidiabetic activities. Moreover, very little is known about the molecular mechanisms underlying antidiabetic activities of SD. Flavonoids exist at a high level in SD. The aim of this study is to evaluate the antidiabetic effects of total flavonoids from SD (SDF) in type 2 Diabetes mellitus (T2DM) rats. T2DM rats were induced by 4 weeks high-fat diet and a singular injection of streptozotocin (STZ) (35mg/kg). Then T2DM rats were treated with SDF for 21 days, using normal saline as the negative control. For comparison, a standard antidiabetic drug, metformin (200mg/kg), was used as a positive control. Three weeks later, relative biochemical indexes were determined and histopathological examinations were performed to assess the antidiabetic activities of SDF. SDF not only exhibited a significant hypoglycemic activity, but also alleviated dyslipidemia, tissue steatosis, and oxidative stress associated with T2DM. Moreover, considerable pancreatic islet protecting effects could be observed after SDF treatment. Further investigations revealed a potential anti-inflammation activity of SDF by determining serum levels of interleukin-6 (IL-6), tumor necrosis factor-α (TNF-α) and C-reactive protein (CRP). This study demonstrates both hypoglycemic and hypolipidemic effects of SDF in T2DM rats, suggesting that flavonoids are the major active ingredients accounting for the antidiabetic activity of SD. Alleviating chronic inflammation responses and protecting pancreatic islets are possible mechanisms involved in the antidiabetic activity of SDF.

Chen F ，Xiong H ，Wang J ，Ding X ，Shu G ，Mei Z ... -  《-》