Antidiabetic properties

VEDAVANAM K, SRIJAYANTA s, o reilly j, RAMAN A, WISEMAN H. (1999) Antioxidant action and potential antidiabetic properties of an isoflavonoid-containing soyabean phytochemical extract (SPE). Phytother Res. 13 601-8. 

Some flavonoids, such as procyanidins, have antidiabetic properties because they improve altered glucose and oxidative metabolisms of diabetic states (Pinent and others 2004). Extract of grape seed procyanidins (PE) administered orally to streptozotocin-induced diabetic rats resulted in an antihyperglycemic effect, which was significantly increased if PE administration was accompanied by a low insulin dose (Pinent and others 2004). The antihyperglycemic effect of PE may be partially due to the insuli-nomimetic activity of procyanidins on insulin-sensitive cell lines. 

Other Examples. Good antidiabetic properties have been claimed 594) for compounds of the t5Tpe RR N-C( NH)NHC( NH)NH2 where... 

A number of review articles on the uses of various plants (different parts of plant materials, crude extracts, herbal formulations etc.) as antidiabetic agents have been published time to time. Naturally occurring chemo-types of varying structural skeletons have also been reported to possess antidiabetic properties the purpose of this resume is to represent promising antidiabetic chemical entities of varying structural skeletons isolated from natural sources. 

Because biological systems are highly susceptible to strong experimental variation, it is difficult to compare the effects of added vanadium compounds in studies from different laboratories. It is difficult to design an experiment that can unequivocally differentiate the effectiveness of two different vanadium compounds. These problems have frequently hampered studies of the antidiabetic properties of vanadium compounds using the noninbred Wistar rat strain in which genetic variability of each animal must be added to the list of biological variables. 

In addition to vanadium, other early transition metals have been shown to have antidiabetic properties, which is not surprising, as this class of compounds would be expected to share some chemical functionality. Chromium [110-112], tungsten [113,114], and molybdenum [115,116] all have demonstrated insulin-like properties. 

Vanadium was first used in France in 1899 as a therapeutic agent for diabetes [119] however, this experimental result was buried with time. The modem era of studying the antidiabetic properties of vanadium began in 1979, when it was shown that vanadium was present in muscle and inhibited plasma membrane ion pumps [1], Experiments were then done in tissue culture experiments, where vanadium... 

The ability of streptozotocin to destroy the pancreatic p cells that produce insulin makes an STZ-induced diabetic animal a good model for type 1 diabetes. However, these animals do not become insulin dependent, as human type 1 patients do. In the STZ-treated outbred Wistar rat model, only about 40 to 70% of the animals display antidiabetic responses to vanadium [100], Nevertheless, this type 1 diabetic model is widely used to study the antidiabetic properties of vanadium compounds. 

Not all vanadium chelates have antidiabetic properties in animals. For instance, four mixed 0,S binding bidentate ligand precursors were derived from maltol to yield four new complexes, two pyranthiones and two pyridinethiones. These complexes are hydrolytically stable and had no observable insulin-enhancing properties [147], The ultimate effectiveness of a vanadium-complex as an antidiabetic drug... 

Broca, C., Cross, R., Petit, P., Sanvaire, Y., Manteghetti, M.,Tournies, M., Masiello, P., Gonnis, R. and Riber, C. (1 999) 4-Hydroxy isoleucine - experimental evidence of its insulinotropic and antidiabetic properties. American Journal of Physiology 277(4), E61 7-E623. 

Kumar, G.S., Shetty, A.K., Sambaiah, K. and Salimath, P.V. (2005b) Antidiabetic property of fenugreek seed mucilage and spent turmeric in streptozotocin-induced diabetic rats. Nutrition Research 25, 1021-1028. 

Figure 2.7 N-lsopropyl-thiadiazolyl sulfanilamide (IPTD) 19 was the first sulfonamide that showed antidiabetic properties in the clinics. Carbutamide 20 and tolbutamide 21 are also antidiabetics tolbutamide 21 has a shorter biological half-life than carbutamide 20, due to its methyl group instead of the chlorine atom in addition, tolbutamide does not show antibacterial activity. Glibendamide 22 is an antidiabetic drug with improved therapeutic properties.

The spasmolytic action of cyclandelate, an ester of man-delic acid, was described as early as 1959, but only in later years have its properties been more fully investigated. It appears to act as a calcium channel blocker in smooth muscle and platelets, this effect being partly dne to inhibition of phosphodiesterases. It also produces increased deformability of erythrocytes, the mechanism of which is so far unknown, although phosphodiesterase inhibition may again be responsible. Cyclandelate also rednces the activity of the rate-limiting enzyme in the biosynthesis of cholesterol (HMG-CoA), and its antidiabetic properties may be due to inhibition of aldose rednctase. 

Pithecollobium jiringa (jering fruit) is valued in Malaysia and Indonesia as a dehcacy and for its antidiabetic properties. 

In the realm of thiosugars, the only pyranose known to be a natural product is 5-thio-D-mannose 7 (Figure 9.2), but more complex structures, salacinol 8 and cotalanol 9, have recently been found in plants known for their antidiabetic properties in Indian folk medicine. 

The leaves of Tecoma stans (Bignoniaceae) were studied previously (1) because of their reputed antidiabetic properties, which appear to have been traced to the monoterpene alkaloid fraction. Further studies of this plant by Lins and D arc Felicio (42) have now revealed the presence of two new alkaloids, 7-hydroxy-5,6-dehydroskytanthine (58) and 4-hydroxy-tecoman-ine (59), in the fruits of T. stans. In addition, two known alkaloids, 5/3-hydroxy-skytanthine (44) and tecomanine (55) were obtained. H and 13C NMR data for these known alkaloids were reported for the first time. 

Pharmacological doses of GLP-1 display the full spectrum of activities also in patients with type 2 diabetes (Fig. 2, Table 1). This includes effects on insulin [11,97] and glucagon [11] secretion, gastric emptying [20,97], appetite, and meal size [76]. As a consequence, antidiabetic properties of pharmacological doses of GLP-1 have been examined in patients with type 2 diabetes. 

Zhang, J., Tiller, C., Shen, J., Wang, C., Girouard, G. S., Dennis, D., Barrow, C. J., Miao, M., and Ewart, H. S. (2007). Antidiabetic properties of polysaccharide- and polyphenolic-enriched fractions from the brown seaweed Ascophyllum nodosum. Can. J. Physiol. Pharmacol. 85,1116-1123. 

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