Effects of polysaccharide from pumpkin on biochemical indicator and pancreatic tissue of the diabetic rabbits
Introduction
Type 2 diabetes mellitus has become one of the most common endocrine diseases in clinics worldwide, and accounts for 90% of the overall incidence of diabetes [1]. A significant number of people diagnosed with Type 2 diabetes will develop complications secondary to hyperglycemia. The importance of developing methods for managing and treating diabetes is becoming more urgent. If appropriate therapy is not available, people will face more serious health and social problems. Plants have been an exemplary source of pharmaceutical treatment for diabetes, and many of the currently available drugs have been derived directly or indirectly from them. It is reported that about 800 plants may possess anti-diabetic potential [2]. For example, Ning Yang et al. [3] have demonstrated that polysaccharides of Opuntia monacantha cladode (POMC) extract have beneficial hypoglycemic properties in streptozotocin-induced diabetic rats, the mechanism of which might be similar to that of the anti-diabetic agent dimethylbiguanide. Wang et al. [4] have confirmed the anti-diabetic effect of water-soluble polysaccharide which is isolated from Cynomorium songaricum.
Cucurbitaceae is a plant family generally considered to consist of melons, cucurbits and pumpkins. The pulp of pumpkin, a cucurbita species grown throughout the world in many regions, is a plant recommended for its beneficial and therapeutic properties. The literature reports that the cucurbita species exhibits diverse pharmacological functions; including antioxidant activities, antimicrobial effects and hypoglycemic effects [5], [6], [7], [8], [9]. Li et al. [10] reported that protein-bound polysaccharides extracted from pumpkin significantly increased levels of serum insulin, reduced blood glucose levels and improved glucose tolerance, and hence could be developed as new anti-diabetic agent. Liu et al. [11] reported ported that pumpkin polysaccharides can increase the weight, decrease the blood glucose and lipids levels in diabetic rats. Zhu et al. [12] darides can increase the weight, decrease the blood glucose and lipids levels in diabetic rats. Zhu et al. [12] demonstrated that pumpkin polysaccharides (PCE-CC) can cut down the blood glucose of the diabetic rats, enhance the SOD activity and reduce the production of MDA and NO, and improve the ultrastructural features of islet cell; all of which support the investigation of PCE-CC for the treatment of diabetes.
Despite this evidence, the literature about the effect of PCE-CC on diabetes is very limited. As far as we know, there is no report about the dynamic changes of the concentrations of blood glucose (BG), total cholesterol (TC), total triglyceride (TG) and glycosylated hemoglobin (HbA1c) in plasma of rabbits of pumpkin polysaccharides. Especially no reports about the effect of pumpkin polysaccharides to the levels of HbA1c have been found. Rowley et al. [13] considered the screening for the diagnosis of DM using the measurement of HbA1c as a potential advantage, compared to the fasting plasma glucose (FPG) and the oral glucose tolerance test (OGGT). Inoue et al. [14] performed a retrospective study of 7 years on 449 subjects in the age-range of 23–65 years, it could be affirmed by those authors, that the combined use of FPG and HbA1c is a convenient and functionally sensitive way of identifying individuals who are at increased risk of developing DM in the future.
Therefore, the dynamic changes of BG, TC, TG, HbA1c, and also the recovery of injured islet cells were investigated in vivo using alloxan-induced diabetic model rabbits to study the anti-diabetic effect of PCE-CC.
Section snippets
Chemicals
Alloxan was purchased from Sigma Chemical Co (St Louis, MO, USA). Standard sample of the molecular weight of dextran was purchased from SHODEX Ltd. Japan; Sephadex G-100 and Sephadex G-200 were bought from GE Ltd. USA; TC and TG were assayed using Kits from BioSino Biotechnology Co., China. A one touch gluco-meter was purchased from Roche Diagnostics, Germany for analysis of BG. All other chemicals used were of analytical grade.
Animals
Japanese white rabbits of both sexes with 2.2 ± 0.4 kg of body weight
Effects of PCE-CC on body weight of rabbits
As shown in Table 2, the body weight (BW) of group I increased regularly from 2.30 ± 0.23 kg to 2.58 ± 0.39 kg during the three week test. The negative group (II) showed an obvious decrease in body weight from 2.33 ± 0.24 kg to 1.94 ± 0.31 kg. In the positive group (III), receiving 50 mg/kg body weight of Xiaoke pill for 3 weeks, the body weight was slightly increased from initial body weight (2.31 ± 0.27 kg) to (2.47 ± 0.28 kg). In the PCE-CC group (IV), receiving 75 mg/kg body weight of PCE-CC for 3 weeks, the
Discussion
C. moschata, comprised of a large amount of polysaccharides, exhibits potent antioxidant and pharmacological properties. In the present study, the anti-diabetic potential of PCE-CC in alloxan-induced diabetic rabbits was examined. Alloxan is a compound known for inducing an insulin deficiency in most experimental models with some remarkable similarities to the human insulin-dependent diabetes mellitus [21]. The diabetogenic agent alloxan is a hydrophilic and chemically unstable pyrimidine
Conclusions
In this experiment, solvent extraction (water and alcohol) was used to extract raw polysaccharide from pumpkin. Sevage method could precipitate 93.12% of proteins. Using ion exchange chromatography, Sephadex G-100 and G-200 gel chromatography to purify PCE-CC, and finally PCE-CCH was collected. PCE-CCH is a type of macromolecule polysaccharide with rhamnose, arabinose, glucose and galactose as its main compositions and little amount hexuronic acid.
The pumpkin polysaccharide had beneficial
Acknowledgements
The financial support provided by the Zhejiang Provincial Scientific Research Foundation (no. LY13C200007), and Key innovation team Project of Science and Technology Department of Zhejiang Province of China (no. 2010R50028) is greatly appreciated.
References (31)
- et al.
J. Ethnopharmacol.
(2002) - et al.
Innov. Food Sci. Emerg.
(2008) - et al.
Food Chem.
(2010) - et al.
Sci. Hortic. (Amsterdam)
(2008) - et al.
Diabetes Res. Clin. Pract.
(2007) - et al.
Anal. Biochem.
(1962) - et al.
J. Biol. Chem.
(1949) - et al.
J. Ethnopharmacol.
(2005) - et al.
Am. J. Med.
(2005) - et al.
Eur. J. Vasc. Endovasc.
(2006)
Arch. Gerontol. Geriatr.
J. Ethnopharmacol.
Diabetes Res. Clin. Pract.
Food Res. Int.
J. Chin. Food Sci. Technol.
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