Marine Heterocyclic Compounds That Modulate Intracellular Calcium Signals: Chemistry and Synthesis Approaches

Intracellular Ca²⁺ plays a pivotal role in the control of a large series of cell functions in all types of cells, from neurotransmitter release and muscle contraction to gene expression, cell proliferation and cell death. Ca²⁺ is transported through specific channels and transporters in the plasma membrane and subcellular organelles such as the endoplasmic reticulum and mitochondria. Therefore, dysregulation of intracellular Ca²⁺ homeostasis may lead to cell dysfunction and disease. Accordingly, chemical compounds from natural origin and/or synthesis targeting directly or indirectly these channels and proteins may be of interest for the treatment of cell dysfunction and disease. In this review, we show an overview of a group of marine drugs that, from the structural point of view, contain one or various heterocyclic units in their core structure, and from the biological side, they have a direct influence on the transport of calcium in the cell. The marine compounds covered in this review are divided into three groups, which correspond with their direct biological activity, such as compounds with a direct influence in the calcium channel, compounds with a direct effect on the cytoskeleton and drugs with an effect on cancer cell proliferation. For each target, we describe its bioactive properties and synthetic approaches. The wide variety of chemical structures compiled in this review and their significant medical properties may attract the attention of many different researchers.     

Dynamics of phytate-zinc balance of fungi fermented cassava products (gari and flour)

Parsley is one of the medicinal herbs used by diabetics in Turkey. It has been reported to reduce blood glucose levels. In this study the effects of feeding parsley on diabetes-induced free radical mediated injury in rat aorta and heart tissues were investigated. Swiss albino rats were divided into six groups: Control, diabetic, parsley, diabetic + parsley, glibornurid, and diabetic + glibornurid. Rats were subjected to i.p. streptozotocin (STZ, 65 mg/kg) to induce diabetes. On the fourteenth day of the study, either parsley (2 g/kg) or glibornurid (5 mg/kg) were given for 28 days to the diabetic rats. Aorta and heart tissue lipid peroxidation and glutathione levels as well as blood glucose levels were determined. The results of the present study indicate that lipid peroxidation was increased and glutathione levels were decreased in both aorta and heart tissue of the diabetic rats. However, treatment of the diabetic rats with either parsley or glibornurid reversed the effects of diabetes on blood glucose, and tissue lipid peroxidation and glutathione levels.     

小麦胚乳传递细胞发育的结构观察

为从细胞学方面了解小麦产量和品质的形成机制,以扬麦5号为材料,利用光镜和透射电镜观察了小麦颖果发育过程中胚乳传递细胞的结构变化,并探讨了胚乳传递细胞的生理功能。结果表明：（1）胚乳传递细胞是胚乳发育过程中最早分化的细胞类型,它们发生在紧邻胚乳腔的胚乳表层,由位于外侧1~2层糊粉层传递细胞和位于内侧1~2层内胚乳传递细胞构成;（2）颖果发育成熟时,内胚乳传递细胞核衰亡,糊粉层传递细胞核依然完整;（3）胚乳传递细胞发育呈明显的极性,且具时空性;（4）糊粉层传递细胞胞质较浓,富含粗面内质网、线粒体、高尔基体和脂质体;质膜皱褶,在局部区域外翻,形成众多的原生质管;（5）内胚乳传递细胞胞质较稀,液泡化程度较高,富含淀粉体;（6）胚乳传递细胞未加厚以及未形成壁内突的壁区域分布有大量的胞间连丝;（7）胚乳传递细胞中线粒体呈极性分布,即质膜附近线粒体的密度较大。根据胚乳传递细胞的结构特点推测,经胚乳传递细胞的养分输送既可通过质外体途径又可通过共质体途径来完成。     

Beta cell protective effects of sodium tungstate in streptozotocin-induced diabetic rats: glycemic control, blockage of oxidative stress and beta cell histochemistry

Background: Diabetes is a major public health problem. The development of new therapies that are able to improve glycemia management and even to cure diabetes is of great interest. In this study, protective effects of sodium tungstate against STZ-induced beta-cell damages were investigated. Methods: Sixty rats were divided into six groups: control, diabetic, sodium tungstate treated diabetic rats from one week before STZ injection (TDB), food-restricted diabetic (FRD), tungstate treated control, sodium tungstate treated diabetic rats from one week after STZ administration (TDA). We evaluated serum insulin, glucose and glucose tolerance; liver glycogen content, glucokinase (GK) activity; blood and pancreas antioxidant power, lipid peroxidation; and fuchsin-aldehyde histochemical staining of beta-cells. Results: Blood glucose levels of TDB group were lower than other diabetic groups (P<0.01). Blood insulin levels of all diabetic groups were lower than controls (P<0.01). Glucose intolerance improved in TDB animals. Blood and pancreas antioxidant power, liver glycogen contents and GK activities and granulated beta cells increased in TDB rats in comparison with other diabetic groups (P<0.01). Likewise, lipid peroxidation decreased significantly in TDB rats (P<0.01). Conclusions: Results suggested that sodium tungstate if administrated before STZ injection improves glycemic state by a direct effect on pancreatic beta-cells and preserves them by reducing the activity of these cells at the time of STZ injection, reducing STZ-induced oxidative stress, reducing insulin secretion, or all of the above mentioned.     

Marine Toxins Targeting Ion Channels

This introductory minireview points out the importance of ion channels for cell communication. The basic concepts on the structure and function of ion channels triggered by membrane voltage changes, the so-called voltage-gated ion channels (VGICs), as well as those activated by neurotransmitters, the so-called ligand-gated ion channel (LGICs), are introduced. Among the most important VGIC superfamiles, we can name the voltage-gated Na⁺ (Na_V), Ca²⁺ (Ca_V), and K⁺ (K_V) channels. Among the most important LGIC super families, we can include the Cys-loop or nicotinicoid, the glutamate-activated (GluR), and the ATP-activated (P2X_nR) receptor superfamilies. Ion channels are transmembrane proteins that allow the passage of different ions in a specific or unspecific manner. For instance, the activation of Na_V, Ca_V, or K_V channels opens a pore that is specific for Na⁺, Ca²⁺, or K⁺, respectively. On the other hand, the activation of certain LGICs such as nicotinic acetylcholine receptors, GluRs, and P2X_nRs allows the passage of cations (e.g., Na⁺, K⁺, and/or Ca²⁺), whereas the activation of other LGICs such as type A γ-butyric acid and glycine receptors allows the passage of anions (e.g., Cl⁻ and/or HCO₃⁻). In this regard, the activation of Na_V and Ca_V as well as ligand-gated cation channels produce membrane depolarization, which finally leads to stimulatory effects in the cell, whereas the activation of K_V as well as ligand-gated anion channels induce membrane hyperpolarization that finally leads to inhibitory effects in the cell. The importance of these ion channel superfamilies is emphasized by considering their physiological functions throughout the body as well as their pathophysiological implicance in several neuronal diseases. In this regard, natural molecules, and especially marine toxins, can be potentially used as modulators (e.g., inhibitors or prolongers) of ion channel functions to treat or to alleviate a specific ion channel-linked disease (e.g., channelopaties).     

水稻 (Oryza sativa L.)花粉及花药壁发育的超微结构研究

 运用透射电子显微镜技术,系统观察了水稻花粉及其花药壁层的发育过程,发现了一些新的现象：(1)小孢子母细胞减数分裂期间,伴随核内染色体变化的同时细胞质发生了“改组”现象,主要表现为核糖体分布密度的规律性变化,这标志着孢子体向配子体的转变。(2) 小孢子外壁的发育始于四分体晚期,最早表现在四分孢子质膜上沉积了少量的壁物质。随后沉积增多,至小孢子早期即形成初生外壁。此后外壁发育迅速,到小孢子晚期外壁已基本发育完成。(3)小孢子中期,小孢子细胞核的双层核膜局部分开,并逐渐扩张成一个“大泡”。核膜扩张在这一时期是一种普遍现象。(4)在花粉发育过程中,绒毡层细胞结构发生明显变化：小孢子母细胞形成之初,绒毡层细胞结构完整,内质网极少;随着减数分裂的进行,绒毡层胞质浓缩,细胞内出现“空腔”,内质网丰富;到了小孢子中期,仍有较多堆叠的内质网,此后逐渐消失。表明内质网在绒毡层的发育中起着重要的物质合成及运输作用。(5)花粉完全成熟时,花药中层细胞的壁以及绒毡层的外切向壁紧贴在一起,形成了一叠合的“壁”结构。     

Pancreatic islet beta cell protective effect of oral vanadyl sulphate in streptozotocin-induced diabetic rats, an ultrastructure study

We sought to determine the ultrastructure of pancreatic islet beta cells of streptozotocin-induced diabetic rats treated with oral vanadyl sulphate. Diabetes was induced in male Wistar rats by intravenous injection of 40 mg kg(-1) streptozotocin. The same volume of normal saline was injected in sham animals. Animals were divided into treated and control groups. Vanadyl sulphate was added to the drinking water of the treated animals at a concentration of 1 mg mL(-1) up to three months. Two months after vanadyl sulphate withdrawal animals were killed. Ultrastructure of islet beta cells were studied by transmission electron microscope. In diabetic treated rats plasma glucose and fluid intake returned to normal levels within three months while control animals remained diabetic. Well granulated cytoplasm, well developed endoplasmic reticulum, increase in the number of immature granules in the cytoplasm with no clear signs of cell injury were found in the islet beta cells of diabetic treated rats. Lymphocyte filteration, nuclear picnosis, cytoplasmic vacuolization were found frequently in the islet beta cells of untreated diabetic rats. In conclusion as was evident in thin sections of panceatic islet beta cells of treated diabetic rats in this study, vanadyl sulphate through preserving islet beta cells structure and ultrastructure contributes in reversing diabetic signs and symptoms in streptozotocin induced diabetic rats.     

Protective Effect of Vitamin E against Diabetes-Induced Oxidized LDL and Aorta Cell Wall Proliferation in Rat

Background:

Hyperlipidemia and oxidized-low-density lipoproteins (Ox-LDL) are important independent cardiovascular risk factors that have been shown to stimulate vascular smooth muscle cell (VSMC) proliferation. The purpose of the present study was to investigate the effect of vitamin E on Ox-LDL, lipid profile, C-reactive protein (CRP), and VSMC proliferation of rat aorta.

Methods:

Male Wistar rats (n = 32) were divided into four groups namely: sham (SH), control (C), non-treated diabetic, and vitamin E-treated diabetic (VETD) groups. Ox-LDL, lipid profile, CRP and VSMC proliferation of aorta were measured after 42 days.

Results:

The results revealed that along with a significant increase in VSMC proliferation, the amount of CRP, Ox-LDL, and lipid profiles in diabetic rats. VSMC proliferation was significantly ameliorated, and elevated CRP, Ox-LDL, and lipid profiles were also restored to those of shams in VETD.

Conclusions:

These findings strongly support the idea that diabetes induces Ox-LDL-mediated oxidative stress and VSMC proliferation in aorta of rat and imply that vitamin E has a strong protective effect as an antioxidant. Key Words: Ox-LDL, Vitamin E, Diabetes, VSMC proliferation     

Levo-Carnitine Reduces Oxidative Stress and Improves Contractile Functions of Fast Muscles in Type 2 Diabetic Rats

Background: Metabolic derangements in type 2 diabetes mellitus (T2DM) are likely to affect skeletal muscle contractile functions adversely. Levo-carnitine improves muscle contractile functions in healthy humans and rats and corrects metabolic derangements in T2DM. Therefore, it is likely to improve muscle contractile functions in T2DM as well. This study was designed to determine the effect of levo-carnitine on serum levo-carnitine levels, oxidative stress and contractile parameters of fast muscle in T2DM. Methods: Ninety Sprague-Dawley rats were randomly divided into three equal groups. Healthy rats served as the controls, while T2DM was induced in diabetic and carnitine groups. The carnitine group was administered levo-carnitine 200 mg/kg/day intraperitoneally for 6 days. At 28^th day, extensor digitorum longus muscles were removed and their functions were assessed using iWorx data acquisition unit (AHK/214). Blood obtained by intra-cardiac sampling at 28^th day was used for estimation of serum malondialdehyde (MDA) and levo-carnitine levels. Results: Maximum isometric twitch tension, time-to-peak twitch tension and time-to-relax to 50% of the peak twitch tension were not significantly different amongst the groups. Carnitine group showed significant improvement in maximum fused tetanic tension, maximum fused tetanic tension after fatigue protocol and recovery from fatigue after 5 minutes of rest period compared to the diabetic group. Serum MDA levels were reduced, while serum levo-carnitine levels were elevated significantly in carnitine group as compared to the diabetic group. Conclusion: Levo-carnitine supplementation increases serum levo-carnitine levels which decreases oxidative stress. This action improves contractile force but delays fatigue in fast muscles of diabetic rats. Key Words: Type 2 diabetes mellitus (T2DM), Levo-carnitine, Fast muscles, Contractile functions, Oxidative stress     

Chitosan Oligosaccharide Alleviates Abnormal Glucose Metabolism without Inhibition of Hepatic Lipid Accumulation in a High-Fat Diet/Streptozotocin-Induced Diabetic Rat Model

This study investigated the effects of chitosan oligosaccharide (COS) on glucose metabolism and hepatic steatosis in a high-fat (HF) diet/streptozotocin-induced diabetic rat model. Male Wistar rats were divided into: (1) normal control (NC group), (2) HF diet (HF group), (3) streptozotocin (STZ)-induced diabetes with HF diet (DF group), and DF group supplemented with (4) 0.5% COS (D0.5F group), (5) 1% COS (D1F group), and (6) 5% COS (D5F group) for 4 weeks. COS supplementation significantly decreased the plasma glucose, BUN, creatinine, uric acid, triglyceride (TG), and total cholesterol (TC) levels, and hepatic glucose-6-phosphatase activity, and significantly increased hepatic hexokinase activity and glycogen content in diabetic rats; but the increased hepatic TG and TC levels could not be significantly decreased by COS supplementation. Supplementation of COS increased superoxide dismutase activity and decreased lipid peroxidation products in the diabetic rat livers. COS supplementation significantly increased phosphorylated AMP-activated protein kinase (AMPK) protein expression, and attenuated protein expression of hepatic phosphoenolpyruvate carboxykinase (PEPCK) and phosphorylated p38 and renal sodium-glucose cotransporter-2 (SGLT2) in diabetic rats. These results suggest that COS may possess a potential for alleviating abnormal glucose metabolism in diabetic rats through the inhibition of hepatic gluconeogenesis and lipid peroxidation and renal SGLT2 expression.     

Protective Effect of Potato Peel Powder in Ameliorating Oxidative Stress in Streptozotocin Diabetic Rats

The potential of dietary potato peel (PP) powder in ameliorating oxidative stress (OS) and hyperglycemia was investigated in streptozotocin (STZ)-induced diabetic rats. In a 4-week feeding trial, incorporation of potato peel powder (5 and 10%) in the diet of diabetic rats was found to significantly reduce the plasma glucose level and also reduce drastically the polyuria of STZ diabetic rats. The total food intake was significantly reduced in the diabetic rats fed 10% PP powder compared to the control diabetic rats. However, the body weight gain over 28 days was nearly four times greater in PP powder supplemented diabetic rats (both at 5 and 10%) compared to the control diabetic rats. PP powder in the diet also decreased the elevated activities of serum transaminases (ALT and AST) and nearly normalized the hepatic MDA and GSH levels as well as the activities of specific antioxidant enzymes in liver of diabetic rats. The result of these studies clearly establishes the modulatory propensity of PP against diabetes induced alterations. Considering that potato peels are discarded as waste and not effectively utilized, these results suggest the possibility that PP waste could be effectively used as an ingredient in health and functional food to ameliorate certain disease states such as diabetes.     

The effects of oral vitamin E on induction and consequence of experimental diabetes mellitus in rats

Streptozotocin destroys the beta-cells of pancreas by generation of reactive oxygen species and vitamin E has documented antioxidant properties. To evaluate the preventive effect of vitamin E on induction of diabetes by streptozotocin and effect of oral vitamin E consumption on carbohydrate and lipid metabolism, forty male Wistar rats divided randomly to control, E1, E2 and E3 groups. The diet of E1, E2 and E3 groups were supplemented with 1, 2 and 4 g kg(-1) of vitamin E, respectively. Four days later all rats were made diabetic by IP injection of 45 mg kg-' streptozotocin and blood glucose was measured 72 h later to determine the severity of blood glucose elevation. Glycosylated hemoglobin, triglyceride, total cholesterol and HDL-c were measured and LDL-c and VIDL-c calculated in plasma of 6 diabetic rats with glucose more than 200 mg dL(-1) in each groups 21 days after streptozotocin injection. Vitamin E had no effect on diabetes induction by streptozotocin, but elevation of glycosylated Hb and reduction of LDL-c in group E3 were significant. Vitamin E also increased HDL-c although it was not statistically significant. We suggest that oral vitamin E consumption may have some beneficial effect on the correction of lipid metabolism disorders of diabetes, although it may worsen carbohydrate metabolism in mild diabetes.     

Effect of flax seeds and date palm leaves extracts on serum concentrations of glucose and lipids in alloxan diabetic rats

The aim of the present investigation was to examine the effect of Flax Seeds (FS) and Date Palm Leaves (DPL) extracts on the concentration of serum glucose and lipids in alloxan diabetic rats. Rats were divided into six groups, normal control rats (without treatment with either FS or DPL), normal control rats treated with either FS or DPL extract for four weeks, diabetic control rats and diabetic rats treated with either FS or DPL extract for four weeks. The concentration of glucose in diabetic rats treated with FS (D+FS) for four weeks was significantly decreased from 17.20 +/- 2.33 to 8.14 +/- 0.54 mmol L(-1) (p < 0.001). Serum total cholesterol concentration (TC) of diabetic rats treated with either FS or DPL extract showed significant decrease by 40 and 31% respectively in the fourth week. Also, serum low density lipoprotein cholesterol (LDL-C) concentration was significantly decreased after two weeks of treatment (p < 0.001 and p < 0.01, respectively). However, no significant changes were obtained in serum high density lipoprotein cholesterol (HDL-C) concentration. Results of the present study showed that FS extract has a hypoglycaemic effect against alloxan diabetic rats. Present findings also showed that treatment of alloxan diabetic rats with either FS or DPL extract significantly decreased serum concentration of TC and LDL-C. Present findings suggest that both of FS and DPL extracts could have a protective effect against diabetes complications as well as against hyperlipidemia through improvement of lipid profile.     

Lipid peroxidation alterations in type 2 diabetic patients

It was studied that type 2 diabetes mellitus is connected with increased plasma lipid peroxidation (lipid peroxidation expressed as malondialdehyde). This review aimed to evaluate the state of lipid peroxidation among type 2 diabetic subjects. Present finding showed that lipid peroxidation increased in type 2 diabetes mellitus. Increased lipid peroxidation maybe is associated with some diseases such as cancer, cardiovascular diseases and diabetes mellitus. Lipid peroxidation has an important role in the pathogenesis and the complications of diabetes. Antioxidants have been found to prevent the progression and occurrence of diabetes. There are several mechanisms that may cause lipid peroxidation affront in diabetic subjects, although, their precise contributions are not completely clear. We proposed that production of free radicals can be reduced by preventing high blood glucose levels and by the control of instabilities in blood glucose levels. A contributor to these instabilities in blood glucose is glycaemic control by using of fast blood sugar test. Furthermore, the earlier assessment of the advancement of diabetes that firmly control of blood glucose can be obtained; the greater will be the decrease in diabetic complications. Patients with type 2 diabetes may have very high physiological antioxidants requirements.     

Chronic Aerobic Exercise Decreases Lectin-Like Low Density Lipoprotein (LOX-1) Receptor Expression in Heart of Diabetic Rat

Background:

Overexpression of lectin-like low density lipoprotein (LOX-1) receptor plays an important role in hyperglycemia-induced vascular complications such as atherosclerosis. Based on the beneficial effects of exercise on preventing cardiovascular complications of diabetes, we aimed to examine the protective effects of aerobic exercise on expression of LOX-1 receptor and production of free radicals in the heart of diabetic rats.

Methods:

Four groups of rats were used: (n = 5 per group): sedentary normal, trained normal, sedentary diabetes and trained diabetes. Diabetes was induced by a single intraperitoneal injection of streptozotocin (50 mg/kg). The exercise protocol was consisted of swimming 30 min/day, 5 days/week for eight weeks. Plasma glucose was evaluated at initiation, weeks 4 and 8 of experiment. At the end of experiment, rats were sacrificed and the heart was removed for determination of nitrate, malondialdehyde, and LOX-1 gene expression.

Results:

In normal non-diabetic rats, the blood glucose level was <150 mg/dl; however, the induction of diabetes resulted in levels more than >400 mg/dl. Gene expression of LOX-1 was increased in the heart of diabetic rats. Exercise reduced the gene expression of this protein in diabetic states without reducing the blood glucose. Finally, swimming exercise decreased the malondialdehyde and nitrate levels in heart tissue both in control and diabetic rats.

Conclusion:

Swimming exercise reduces heart expression of the LOX-1 receptor in accompany with reduction of free radicals production. Since these parameters are important in generation of diabetic complications, swimming exercise is a good candidate for reducing these complications. Key Words: Hyperglycemia, Diabetic complications, LOX-1 receptor, Exercise, Free radicals     

Effects of Nitrogen Application on the Development and Accumulation of Protein Bodies in Developing Rice Seed

Abstract

We examined the nature of protein bodies affected by nitrogen application in developing rice endosperm using scanning and transmission electron microscopes. Protein body type II, Pb-II, was observed at the first week after heading independent of nitrogen application, whereas protein body type I, Pb-I, was not observed in either the low nitrogen or non-fertilized group. However, in the high nitrogen group, Pb-I was also observed at 1 week after heading. Pb-I was formed by enlargement of endoplasmic reticulum cisternae, but Pb-II had a close relationship with the Golgi apparatus and was accumulated in the envelope-like vacuole. The smallest protein body, Pb-III, about 0.6-0.8 μm in diameter, appeared at 2 weeks after heading, and the amounts of this protein body increased substantially at 3 weeks after heading. This protein body also originated from endoplasmic reticulum cisternae. Pb-I was observed only in cytoplasm, but, Pb-II appeared in both the endoplasmic reticulum and envelope-like vacuole. The amount of protein bodies in the rice endosperm cell varied with the cultivar and amount of nitrogen applied. In cv. Koshihikari (Japonica), the application of much nitrogen increased the amount of protein bodies not only in the subaleurone, but even in the fifth layer from the aleurone layer. However, in cv. Belle patna (Indica), the application of much nitrogen increased the amount of protein bodies up to the sixth ayer of aleurone layer, and caused the accumulation of a few protein bodies even in the central part of endosperm. It was concluded that storage protein transported by Golgi vesicles and rough endoplasmic reticulum (RER) plays an important role in the accumulation of reserve substances in rice seed. Development of mitochondria and RER was enhanced by the application of nitrogen.     

Quantitative Assessment of Proliferative Effects of Oral Vanadium on Pancreatic Islet Volumes and Beta?Cell Numbers of Diabetic Rats

Background:

Oral vanadyl sulfate (vanadium) induces normoglycemia, proliferates beta cells and prevents pancreatic islet atrophy in streptozotocin-induced diabetic rats. Soteriological method is used to quantitate the proliferative effects of vanadium on beta-cell numbers and islet volumes of normal and diabetic rats.

Methods:

Adult male Sprague-Dawley rats were made diabetic with intravenous streptozotocin injection (40 mg/kg). Normal and diabetic rats were divided into four groups. While control normal and diabetic (CD) groups used water, vanadium-treated normal (VTN) and diabetic (VTD) groups used solutions containing vanadyl sulfate (0.5-1 mg/mL, VOSO₄+5H₂O). Tail blood samples were used to measure blood glucose (BG) and plasma insulin. Two months after treatment, rats were sacrificed, pancreata prepared, and stereology method was used to quantitatively evaluate total beta cell numbers (TBCN) and total islet volumes (TISVOL).

Results:

Normoglycemia persisted in VTN with significantly decreased plasma insulin (0.190.08 vs. 0.970.27 ng/dL, P<0.002). The respective high BG (53249 vs. 14446 mg/dL, P<0.0001) and reduced plasma insulin (0.260.15 vs. 0.540.19 ng/dL, P<0.002) seen in CD were reversed in VTD during vanadium treatment or withdrawal. While the induction of diabetes, compared to their control, significantly decreased TISVOL (1.90.2 vs. 3.030.6 mm³, P<0.003) and TBCN (0.990.1 vs. 3.20.2 x 10⁶, P<0.003), vanadium treatment significantly increased TISVOL (2.90.8 and 4.071.0 mm³, P<0.003) and TBCN (1.50.3 and 3.80.6 x 10⁶, P<0.03).

Conclusion:

Two-month oral vanadium therapy in STZ-diabetic rats ameliorated hyperglycemia by partially restoring plasma insulin. This action was through proliferative actions of vanadium in preventing islet atrophy by increasing beta-cell numbers.Key Words: Vanadium, Pancreas, Islet volumes, Rats     

Effect of Bitter Gourd (<Emphasis Type="Italic">Momordica charantia</Emphasis>) on Glycaemic Status in Streptozotocin Induced Diabetic Rats

Bitter gourd (Momordica charantia), a commonly consumed vegetable is used as an adjunct in the management of diabetes mellitus. A study was carried out to examine the effect of edible portion of bitter gourd at 10% level in the diet in streptozotocin induced diabetic rats. To evaluate the glycaemic control of bitter gourd during diabetes, diet intake, gain in body weight, water intake, urine sugar, urine volume, glomerular filtration rate and fasting blood glucose profiles were monitored. Water consumption, urine volume and urine sugar were significantly higher in diabetic controls compared to normal rats and bitter gourd feeding alleviated this rise during diabetes by about 30%. Renal hypertrophy was higher in diabetic controls and bitter gourd supplementation, partially, but effectively prevented it (38%) during diabetes. Increased glomerular filtration rate in diabetes was significantly reduced (27%) by bitter gourd. An amelioration of about 30% in fasting blood glucose was observed with bitter gourd feeding in diabetic rats. These results clearly provided experimental evidence that dried bitter gourd powder in the diet at 10% level improved diabetic status signifying its beneficial effect during diabetes.     

Eucalyptus globulus (eucalyptus) treatment of candidiasis in normal and diabetic rats

Background: The leaves of Eucalyptus globulus (eucalyptus) are used for treatment of diabetes mellitus in traditional medicine. The aim of this study was to evaluate the effects of eucalyptus in treatment of established systemic infection with Candida albicans in normal and streptozotocin-induced diabetic rats. Methods: Sixty normoglycemic male Wistar rats, weighing 200-250 g, were selected and randomly divided into six groups (n= 10): normal control, control + C. albicans, control + eucalyptus + C. albicans, diabetic control, diabetic + C. albicans, diabetic + eucalyptus + C. albicans. Diabetes was induced after a single intraperitoneal injection of streptozotocin (60 mg/kg body weight) and eucalyptus was added to the diet (62.5 g/kg) and drinking water (2.5 g/L) of treated animals for 4 weeks. The concerned groups were inoculated with C. albicans 15 days after diabetes induction. At the end of one month experiment, fasted rats were killed by cervical decapitation. Blood was collected from neck vein for estimation of glucose. C. albicans concentrations were estimated in liver and kidneys using serial dilution culture of tissue homogenates. Results: Eucalyptus administration significantly improved the hyperglycemia, polydipsia, polyphagia, and it also compensated weight loss of diabetic rats (P<0.05). Moreover, eucalyptus caused a significant reduction in C. albicans concentration in liver and kidney homogenates (P<0.01). Conclusion: The results revealed that eucalyptus improves Candidia infection in normal and diabetic rats that in some ways validates the traditional use of this plant in treatment of diabetic patients. Key Words: Diabetes mellitus, Eucalyptus globulus, Candida albicans