Cell Biochem Biophys (2015) 71:337–344 DOI 10.1007/s12013-014-0203-2 ORIGINAL PAPER Anti-hyperlipidemic and Anti-oxidative Effects of Gelsemine in High-Fat-Diet-Fed Rabbits Tao Wu • Guoping Chen • Xiaolong Chen • Qiqi Wang • Gang Wang Published online: 12 September 2014 Ó Springer Science+Business Media New York 2014 Abstract The present study investigated the anti-hyper- indicated by the increased activity of superoxide dismutase lipidemic proprieties of a natural alkaloid, gelsemine, in a and catalase, and reduction in serum nitric oxide, and high-fat-fed rabbit model. Animals were randomly divided malondialdehyde concentrations in hyperlipidemic animals into five groups and fed normal diet, hypercholesterolemic that received gelsemine supplementation. Dietary supple- diet (1 % cholesterol), or hypercholesterolemic diet (1 % mentation with gelsemine may, therefore, reverse the effect cholesterol) supplemented with gelsemine (1, 5, or 25 mg/ of the lipogenic diet on lipid profile and hepatic enzymes in kg). After 60 days, serum concentrations of total choles- hyperlipidemic rabbits, and protect tissues from oxidative terol (TC), LDL-C, HDL-C, triglycerides, apolipoproteins stress, caused by high-fat diet. A and B, SGOT, SGPT, glucose, and insulin were mea- sured in all experimental groups. Hypercholesterolemic Keywords Gelsemine Á High-fat diet Á Hyperlipidemia Á diet resulted in significantly elevated levels of TC, TG, Oxidative stress LDL-C, SGOT, and SGPT, and reduced HDL-C compared to the normocholesterolemic diet group. Gelsemine treat- ment significantly improved lipid profile parameters, Introduction affected by hyperlipidemia, while having no effect on the levels of apolipoproteins, glucose, and insulin. Further- Cardiovascular and cerebrovascular diseases are the most more, gelsemine treatment decreased hyperlipidemia- frequent causes of morbidity and mortality in the US and induced oxidative stress in a dose-dependent manner, as other western countries. Atherosclerosis and subsequent formation of lesions as a result of accumulation of lipids and fibrous elements in the sub endothelial space of large & T. Wu ( ) Á Q. Wang arteries are considered the primary causes of these vascular Department of Cardiology, The First Affiliated Hospital, School of Medicine, Zhejiang University, Hangzhou 310003, China diseases [1–4]. Pathogenesis of atherosclerosis includes e-mail: [email protected] both modifiable and non-modifiable risk factors that col- lectively contribute to the development, progression, and G. Chen rupture of atherosclerotic plaque [1–4]. Growing evidence Department of Endocrinology, The First Affiliated Hospital, School of Medicine, Zhejiang University, Hangzhou 310003, indicates that chronic and acute overproduction of reactive China oxygen species (ROS) under pathophysiologic conditions has a causal role in atherosclerosis and other cardiovascular X. Chen diseases. Oxidative stress results from an imbalance School of Pharmacy, Shanghai Jiaotong University, Shanghai 200030, China between radical-generating and radical-scavenging sys- tems, i.e., increased free radical production, reduced G. Wang activity of antioxidant defenses or both [5]. Recent studies Tumor Institute of Integrated Chinese and Western Medicine, suggest that the role of oxidative stress in the pathogenesis Zhejiang Academy of Traditional Chinese Medicine, Tongde Hospital of Zhejiang Province, Hangzhou 310007, Zhejiang, of atherosclerosis is due not only to the generation of free China oxygen radicals, but also to nonenzymatic protein 123 338 Cell Biochem Biophys (2015) 71:337–344 glycosylation, auto-oxidation of glucose, impaired gluta- effects on cardiac dysfunction induced by hyperglycemia/ thione metabolism, alteration in the function of antioxidant hypercholesterolemia through decreasing cardiac lipid enzymes, and lipid peroxides formation [5]. The defense accumulation and promoting glucose transport [11]. It is mechanisms against free radicals include glutathione possible that other natural alcaloids may have similar (GSH), superoxide dismutase (SOD), glutathione peroxi- pharmacological effect in hypercholesterolemic animal dase (GPx), and catalase (CAT), which contribute to models. Hence, our experiments were aimed to explore the elimination of superoxide, hydrogen peroxide, and hydro- effects of gelsemine on serum lipid profile, liver enzymes, xyl radicals [5]. Recent advances in the field of free radical glucose, and insulin, and to evaluate its protective propri- research have confirmed that foods rich in antioxidants eties against oxidative stress, induced by high-fat diet in a play an important role in the prevention of cardiovascular rabbit model of hyperlipidemia. disease [2, 6–8], and there is an accumulating amount of evidence, indicating that botanical dietary supplements can prevent the development of atherosclerosis [2]. Therefore, Materials and Methods plant derived antioxidants are now receiving special attention. Gelsemine is a natural alkaloid extracted from Reagents Gelsemium, a small genus of the family Loganiaceae, which comprises three popularly known species: Gelse- All reagents were purchased from Sigma (Sigma-Aldrich, mium elegans Benth. (G. elegans), which is native to China St. Louis, MO, USA) unless otherwise stated. and Southeast Asia, Gelsemium sempervirens Ait. (G. sempervirens) and Gelsemium rankinii Small (G. rankinii), Grouping and Treatments native to North America. G. sempervirens has long been used as a traditional folk medicine to alleviate pain and Adult male rabbits of New Zealand strain weighing reduce anxiety, and has shown promising results in vivo, as 1.25–2.50 kg were purchased from Shanghai Laboratory even very low doses of G. sempervirens extract reduce Animal Center, Chinese Academy of Sciences. Rabbits anxiety in animal models [9, 10]. G. elegans is a well- were maintained in animal stainless steel mesh-bottomed known plant in Asia, and although it can be toxic, it has cages for 2 weeks at 21–24 °C and 12 h light/dark cycle. been used in Chinese medicine as an anti-inflammatory, Animals were fed a standard basal diet for 2 weeks for analgesic, and antineoplastic agent [9, 10]. The alkaloids adaptation. Following the initial 2 weeks, nourishment was gelsemine, koumine, gelsenicine, and gelsevirine constitute done by standard grain food purchased from Shanghai the primary active molecules of G. elegans. Gelsemine is Laboratory Animal Center, containing 15 % protein, the only common alkaloid found in both G. elegans and G. 40–50 % carbohydrates, 2 %vegetable fat, and 15–25 % sempervirens, while koumine, gelsenicine, and gelsevirine fiber. Animals were randomly divided into five groups of are unique for G. elegans. Recently, a number of studies eight animals each to be fed with normal diet, hypercho- have focused on the pharmacology of the G. elegans lesterolemic diet (1 % cholesterol), or hypercholesterol- alkaloids. Similar to alkaloids extracted from G. semper- emic diet (1 % cholesterol) ? gelsemine (1, 5, or 25 mg/ virens, gelsemine, koumine, gelsevirine, and gelsenicine kg). Gelsemine treatment was administered as previously that are extracted from G. elegans by high-speed counter- described [11]. Briefly, gelsemine (99 % purity; Chengdu current chromatography (HSCCC) and pH-zone-refining Biopurify Phytochemicals Ltd, Chengdu, China) was counter-current chromatography (CCC), were reported to reconstituted in 10 % Tween 80 solution for intragastric have analgesic effect [9, 10]. Previous studies reported that administration (i.g.). The study protocol was approved by a single dose of gelsemine, far below the LD50, had a the Medical Ethics Committee of Nanchang University. potent anxiolytic, but not antidepressant effect in mice that could be antagonized by strychnine, a glycine receptor Biochemical Measurements antagonist. These studies suggested that G. elegans alka- loids may be a promising tool in treating anxiety-related Fasted blood samples were collected to determine serum psychiatric disorders [9, 10]. concentrations of total cholesterol (TC), high-density Recent studies have discovered that natural alkaloids, lipoprotein cholesterol (HDL-C), low-density lipoprotein such as berberine, isoquinoline alkaloid, derived from cholesterol (LDL-C), and triglycerides (TG), liver enzymes medicinal herbs including Berberis, Hydrastis canadensis, (serum glutamate oxaloacetate transaminase (SGOT) and Coptis chinensis Franch., and Cortex phellodendri Chin- serum glutamate pyruvate transaminase (SGPT), insulin, ensis, can improve metabolic dysfunction, decrease ven- glucose, and apolipoproteins A and B. Serum insulin levels tricular premature complexes in the patients with were determined by ELISA using a commercially available congestive heart failure [11, 12], and have a protective kit (Monobind Inc., CA, USA). Other biochemical factors 123 Cell Biochem Biophys (2015) 71:337–344 339 were measured by routine enzymatic methods using com- Measurement of Serum Nitric Oxide (NO) mercial kits (Monobind Inc., CA, USA) and analyzed using a Hitachi 902 autoanalyzer (Tokyo, Japan). Serum NO levels were determined spectrophotometrically by measuring the accumulation of its stable degradation products, nitrite and nitrate. The serum nitrite level was Measurement of Serum Reduced Glutathione (GSH) determined by the Griess reagent as described by Hortelano et al. (1995). Briefly, the Griess reagent, a mixture (1:1) of Serum GSH levels were determined as described by Ell- 1 % sulfanilamide in 5 % phosphoric acid and 0.1