Blood Sugar Levels In Rats Research Articles

Formulation and evaluation of physical stability and antidiabetic activity from nanoliposomes containing an ethyl acetate extract of Solanum xanthocarpum Schrader & Wendland fruit in rats

Introduction: The extract of Solanum xanthocarpum fruit has antidiabetic activity. This research aims to formulate nanoliposomes containing ethyl acetate extracts of S. xanthocarpum selected from multilevel extraction, evaluate their physical stability and antidiabetic activity, and compare them with the extract. Methods: The extracts were prepared using n-hexane, ethyl acetate, ethanol, and water as solvents, and their antidiabetic activities were evaluated to select the extract most effective in lowering blood sugar levels in rats. That extract was formulated into three nanoliposomes using varying amounts of phospholipid, cholesterol, and Span 60, i.e., F1 (40 mmol), F2 (50 mmol), and F3 (60 mmol). Various sonication times ranging from 10 to 30 minutes were evaluated for particle size, entrapment efficiency, and physical stability. The selected formulations were evaluated for antidiabetic activity. Results: The ethyl acetate extract showed the highest decrease in glucose in rats and was selected for nanoliposome formulation. The nanoliposomes obtained were physically stable at low temperatures for 12 weeks. F2 had the smallest particle size (143.97 nm) and the greatest entrapment efficiency (92.981% ± 0.35%) with a sonication time of 30 minutes and was significantly different from F1 and F3 (P<0.05). The highest percentage reduction in blood sugar levels was with F2 at 74.57% and significantly differed (P<0.05) from the ethyl acetate extract of S. xanthocarpum at 73.98% and the positive control rat group. Conclusion: The results show the potential uses of the prepared nanoparticles, especially the F2 formulation, as an antidiabetic formula.

Moringa oleifera gum effect on blood sugar levels and rat pancreas histology induced by Streptozotocin

Moringa gum is a product that people can use as an anti-hyperglycemic agent. This study aimed to determine the effectiveness of Moringa gum in reducing blood sugar levels and improving the histology structure of the rat pancreas induced by streptozotocin (STZ). This study used 21 male rats divided into 3 groups including control, diabetes (STZ), and diabetes (STZ + 3% Moringa gum). STZ treatment at a single dose (45 mg/kg BW) was given intraperitoneally, while Moringa gum was given through drinking water for 2 weeks. Blood sugar levels were measured on days 0, 7th, 14th, 21st, and 28th. The results showed that STZ administration induced diabetes in rats with blood sugar levels of 487 mg/dL on the 14th day. Moringa gum administration was able to reduce blood sugar levels on days 21st and 28th respectively to 306 and 234 mg/dl. The histology structure of the pancreas of rats treated with gum also showed improvement. This study concludes that Moringa gum is effective in lowering blood sugar levels in rats even though it still does not show normal blood sugar levels, and can repair STZ-induced damage to the histology structure of the rat pancreas.

Exploration of anti-diabetic activity and metabolite profiling of Bruguiera cylindrica (l.) Bl.-in vivo anti-diabetic activity, exploration of molecular mechanism, and network pharmacological analysis.

The Bruguiera cylindrica L. is a mangrove plant that is typically found in coastal areas of Asia, including India. It has been known for its medicinal properties, which have been utilized for generations. For example, in Thailand, it has been used to treat wounds and diarrhoea, while in India, it has been effective in addressing diabetes, ulcers, and other health issues. This particular study sought to investigate the potential of B. cylindrica bark extract in reducing the symptoms of diabetes in rats. In this study, we examined the potential of B. cylindrica bark extract as an inhibitor of α-amylase and α-glucosidase enzymes in vitro. We also evaluated the effects of the extract and Metformin on rats fed high-fat diets and measured their lipid profiles and biochemical parameters. Furthermore, we conducted a network pharmacology analysis to identify proteins and pathways involved in the amelioration of diabetes. Through metabolite profiling, we identified 58 compounds in B. cylindrica hydroalcoholic extract. These compounds include alkaloids, phenolics, flavonoids, and fatty acids. The extract was found to have a dose-dependent inhibition activity against α-amylase and α-glucosidase, with IC50 values similar to acarbose. In rats, oral administration of 200-400 mg/kg of B. cylindrica led to reduced blood glucose levels and normalized serum biochemical parameters. Bruguiera cylindrica bark may reduce blood sugar levels in rats with diabetes. The study found metabolites that interact with protein targets associated with different types of diabetes.

Anti-hyperglycemic effect of two terpenoids isolated from Coula edulis on normoglycemic rats and in silico study of their potential inhibitors on α-amylase and dipeptidylpeptidase 4

Diabetes causes many deaths around the world, making the search for treatments a real challenge. Plant secondary metabolites are promising candidates because they act as scaffolds in biological processes. This study investigates anti-hyperglycaemic effect of two terpenoids isolated from Coula edulis and in silico study of their potential inhibitors on α-amylase and dipeptidypeptidase 4. After extraction and isolation of the two terpenoids, their structures were characterized using 1D and 2D NMR spectroscopic techniques. Subsequently the anti-hyperglycemic effect was achieved following an overload of starch on the one hand and glucose on the other hand in normoglycemic rats. Each isolated terpenoids was tested at a dose of 3 mg/kg.bw, the same for the reference compounds (Acarbose and glibenclamide). Conformational site analysis and docking parameters such as binding energy, inhibition constant, interaction profiles with diabetes target residues (α-amylase and dipeptidypeptidase 4) were determined using AutoDock 4.2 and Discovery Studio visualizer. The results showed that the terpenoids isolated from coula edulis were Taraxerol and 3β-(Z)-coumaroyltaraxerol, each of its two terpenoids considerably decreased the blood sugar levels in rats after overloading of starch and glucose solutions respectively. Their effects were similar to the reference drugs. Furthermore, the in-silico approach showed that these compounds have good docking scores with α-amylase and with DPP4. Taraxerol exhibited a docking score more than three times than the acarbose docking score. Only 3β-(Z)-coumaroyltaraxerol reacts with at least one amino acid of the α-amylase catalytic triad (Asp 300). Both interact with histidine (His 740) of the DPP4 catalytic triad. In view of this results, taraxerol and 3β-(Z)-coumaroyltaraxerol have anti-hyperglycemic effects and are good candidates for the development of new multitarget antidiabetics.
 Keywords: Coula edulis, RMN 1D and 2D, tarxerol, 3β-(Z)-coumaroyltaraxerol and Anti-hyperglycemia

Antidiabetic Effect of Standardized Chrysanthemum rubellum Hydroethanolic Extract by Targeting α-Glucosidase and the PTP-1B Signaling Pathway for Alleviating Diabetes in Experimental Model.

The study's goal was to find out whether Chrysanthemum rubellum extract has anti-diabetic properties by concentrating on α-glucosidase and the PTP-1B signaling pathway. C. rubellum flowers were used for extraction using Methanol/water (80/20) as solvent. LC-MS techniques was used to check the presence of phytoconstituents present in C. rubellum extract. In vitro antidiabetic activity was evaluated using α-glucosidase inhibitory activity and PTP-1B signaling pathway. On Streptozotocin (STZ)-induced rats with diabetes, the in vivo antidiabetic efficacy was assessed using a test for oral glucose tolerance. The phytoconstituents identified in the extract of C. rubellum were apigenin, diosmin, myricetin, luteolin, luteolin-7-glucoside, and Quercitrin as compound 1-6, respectively. Results showed that diosmin exhibited highest α-glucosidase inhibitory activity i.e. 90.39%. The protein level of PTP-1B was lowered and the insulin signalling activity was directly increased by compounds 1-6. The maximum blood glucose levels were seen in all groups' OGTT findings at 30 minutes following glucose delivery, followed by gradual drops. In comparison to the control group, the extract's glucose levels were 141 mg/dL at 30 minutes before falling to 104 mg/dL after 120 minutes. The current study has demonstrated, in summary, that extract with phytoconstituents reduce blood sugar levels in rats. This finding suggests that extract may reduce the chance of insulin resistance and shield against disorders like hyperglycemia.

Test the Effectiveness of Grape Seed Extract as an Antidiabetic Drug In Male White Rats Wistar Strain

The research aims to know the effectiveness of grape seeds in lowering blood sugar levels in white rats. The research began with grape seed extraction using the maceration method. The results of macerate were given to white rats that were given grape seed extract samples at doses of 75 mg/200 grams BW, 125 mg/200 grams BW, and 250 mg/200 grams BW. The positive control was metformin, and the negative control was given distilled water. All were given treatment for 14 days. On days seven and 14, a blood sugar test was carried out to assess the effectiveness of grape seed extract. The results showed that of the five treatment groups, sample group I (extract at a dose of 75 mg/200 gram BW) and sample group III (extract at a dose of 250 mg/200 gram BW) affected reducing blood sugar levels in rats. This is proven by comparing blood sugar levels after being given alloxan on the seventh day in the two groups, showing better results in reducing blood sugar levels than the other groups. It can be concluded that grape seed extract can properly reduce blood sugar levels in white rats with type II diabetes mellitus.

The Effect Salvia Hispanica L Seed Extract on Blood Sugar Levels in Rats with Moderate Physical Activity

Hyperglycemia is a condition in which the body experiences an increase in the level of sugar in the blood and is a clinical manifestation of diabetes type. This unusual exercise can cause insulin resistance in patients with diabetes. Chia seeds contain a lot of antioxidants, which makes them effective in reducing oxidative stress caused by hyperglycemia and type 2 diabetes. The purpose of this study is to show the difference in the effect of the extraction of chia seeds and moderate exercise high blood sugar in T2DM. limit. and STZ injection. This research method is experimental and post-test control group design only. The number of samples is 15 male wistar rats aged 3-4 months with a weight of 180-200 grams repeated for 7 days, divided into 3 groups at random, that is the treatment group P0 as control, P1 received injection which. STZ and moderate exercise. and chia seed extract dose of 4.5 mg/kg body weight, P2 for STZ injection, for moderate exercise and chia seed extract dose of 13.5 mg/kg body weight/day. The duration of treatment is 7 days. Blood samples are taken from v. Ophthalmica on day 14. Monitor GDS level by spectrophotometer method. The data were analyzed by Anova test. The results of the study showed that the average blood sugar at P0: 128 ± 2.5; P1: 206±3.5; P2: 43.8±1.9. The results of the ANOVA test obtained a P value of 0.000 and the results of the LSD post hoc test between groups obtained a P value of 0.000 (<0.05). The conclusion of the study is that there is an effect of giving chia seed extract doses of 4.5mg/kgBW and 13.5mg/KgBW and moderate exercise can reduce blood sugar in time. Keywords: diabetes mellitus, chia seeds, blood sugar, moderate exercise

Practicality of non-invasive glucagon-loaded dissolving microneedle for life-saving treatment of severe hypoglycemia in a diabetic rat model

The development of dissolving microneedles (DMNs) has brought light to the transdermal delivery of biomolecules that are released into the skin through the rapid dissolution of the matrix material to enter the systemic circulation and exert therapeutic effects. Herein, we aimed to prepare, characterize, and analyze the effectiveness of a glucagon-loaded DMN system that rapidly increases blood sugar levels in rats with diabetic hypoglycemia. The stability and content of biological drugs following DMNs preparation was assessed using circular dichroism and bicinchoninic acid kit for protein determination kits(BCA kits). The maximum drug loading capacity of DMNs was approximately 140 μg in each patch, and the microneedles could be stored for up to 14 days under dry storage conditions. In vitro skin permeation studies were conducted using a Franz diffusion cell apparatus for glucagon-loaded DMNs. To investigate the efficacy of transdermal drug delivery, drug-laden DMNs were administered to rats with hypoglycemic diabetes. Compared to subcutaneous injections, microneedle drug release demonstrated comparable efficacy in raising blood glucose levels in vivo. Therefore, this study demonstrated that glucagon-loaded DMNs may be a promising approach for efficient transdermal drug delivery as an alternative to subcutaneous injection for the treatment of severe hypoglycemia in patients with diabetes.

Antidiabetic Activity of Aqueous Extracts of <i>Laurus nobilis</i>, a Spice Used by Beninese Traditional Therapists

All over the world, humans developed knowledge about the use of medicinal plants to treat all kinds of diseases. Spices were included. This work aimed to evaluate the hypoglycemic property Laurus nobilis, a spice used by traditional therapists in Benin for diabetes management. The aqueous extracts of the leaves of Laurus nobilis were obtained by maceration. The phytochemical screening was carried out. Acute oral toxicity tests by single dose gavage of 2000 mg / kg body weight were performed in female Wistar rats. The weight of the animals, the serum creatinine, the ALT transaminase and the hemoglobin level were determined on day 0 and then on day 14. For the efficacy test, the extract was administered to rats at a concentration of 300 mg / Kg of body weight for 21 consecutive days. The blood tests performed were blood sugar, triglycerides and cholesterol. Histological sections were taken from the liver, kidneys and spleen. The phytochemical screening revealed the presence of tannins, mucilages and flavonoids. There were no deaths of rats and their weights, blood creatinine, ALT transaminase, and hemoglobin levels did not vary significantly during the toxicity study, indicating no toxicity. Regarding the efficacy test, Laurus nobilis extract significantly lowered the mean blood sugar level in rats on day 14 and day 21 (P Laurus nobilis displayed hypoglycemic properties in non-diabetic rats and was not acutely toxic. It could be used in the management of diabetes.

Model Hewan Coba Diabetes Mellitus Yang Diinduksi Streptozocin Terhadap Kadar Gula Darah Dan Pankreas

Objective : The purpose of this study was to determine blood sugar levels and histopathological features of the pancreas in Wistar rats (Rattus norvegicus) induced by Streptozotocin. Methods: The type of research conducted is experimental laboratory in vivo. The research design chosen was True Experimental Pre Test and Post Test Control Group Design with 24 test animals and divided into six different treatment groups. The results were analyzed using SPSS software, and for the histopathological description the rats were dissected and the pancreas was taken for preparation and then stained using the Hematoxylin Eosin (HE) method. Results: The results of this study indicate that the histopathological description of pancreatic tissue is damaged which can be seen from the occurrence of cell necrosis, cell degeneration, collections of inflammatory cell , atherosclerosis and vascular congestion are found. Blood sugar levels of rats given a combination of STZ and high-fat diet significantly increased blood sugar levels (P value < 0.05). Conclusion : There is a significant relationship between blood sugar levels and pancreatic histopathology in Wistar rats (Rattus norvegicus) induced by Streptozotocin and high-fat diet. Keywords: Diabetes mellitus; Blood Sugar Levels; Streptozotocin; Pancreas Histology

Phytochemical Test of Bitter Melon (Momordica charantia L) Herb and its Effect on Rat Blood Sugar Levels

This study aims to determine the class of chemical compounds, phytochemical levels, antihyperglycemic effects, and histopathology of the pancreas of rats treated with bitter gourd (Momordica charantia L) for the treatment of diabetes mellitus. Bitter gourd is made by adding water, then mashed and squeezed. The ingredients were tested for their phytochemical content and antidiabetic power. 15 male rats were divided into 5 groups. Group 1 as a negative control, namely normal rats without treatment, group 2 as a positive control given alloxan, group 3, namely rats given alloxan and bitter melon fruit 0.9 mL, group 4, namely rats given alloxan and bitter melon ingredients 1.8 mL, and group 5, namely rats, were given alloxan and a mixture of bitter melon 3.6 mL. The phytochemical test results of bitter melon fruit contain carbohydrates, alkaloids, saponins, and terpenoids. The total alkaloid content of the bitter melon fruit is 0.232%, the saponin content of the bitter melon fruit is 0.6375%, and the terpenoid content of the bitter melon fruit is 0.5317%. The administration of bitter melon fruit to diabetic rats can reduce blood sugar levels of rats and the histopathological observations of the pancreas of rats show a repair effect on pancreatic damage after administration of bitter melon herb.

Papric Ethanol Extract Test (Capsicum Annuum) on Blood Sugar Levels of Wistar Rat (Rattus Norvegicus) Induced Alloxan

This study aims to determine the effect of paprika ethanol (capsicum annuum) on blood sugar levels of alloxan-induced Wistar rats (rattus norvegicus). This type of research is experimental. The method used was pre test and post test with control group design. The results of this study indicate that for Post Test 1 or after being given treatment for 7 days, the average result shows that there is an effect of giving red paprika ethanol extract on blood sugar levels in Wistar rats where the significant value of each treatment is all less than 0.05. For Post Test 2 or after being given treatment for 14 days, only at a dose of 250 that has no effect on blood sugar levels of the rats, because the significant value is 0.813 greater than 0.05, for other treatments it has a significant effect because the significant value is more smaller than 0.05.

Effect of buspirone on blood glucose levels in rats

Background: Buspirone is commonly used as an anti-anxiety drug. There is controversy over the dysglycemic effects of buspirone in various clinical and animal studies. Aims and Objectives: This study aims to evaluate the effect of buspirone on blood sugar level in rats at three different doses. Materials and Methods: Rats were treated with three doses of buspirone orally, namely, 3 mg/kg, 5 mg/kg, and 10 mg/kg and control group received distilled water orally for 14 days. Blood was collected by tail prick method at 0 h (fasting), at ½ h, 1 h, 1½ h, 2 h, and 4 h after drug administration on day 1. On days 7 and 14, the blood glucose levels were estimated at baseline (0 h) and at 1 h after the drug administration. Blood glucose levels were estimated using the glucometer. Results: On day 1, mean blood glucose values were found to be significantly (P < 0.001) low in control group and in buspirone 3 mg/kg and 5 mg/kg groups at various time intervals as compared to baseline value at 0 h in respective group. In buspirone 10 mg/kg group, mean blood glucose levels at all-time intervals were found to be significantly high (P < 0.01) as compared to baseline value at 0 h. On days 7 and 14, a significant increase in the blood glucose level was observed immediately within 30 min of drug administration and reach maximum value at the end of 1 h only in buspirone 10 mg/kg group. This rise in blood glucose level was not seen in groups receiving buspirone 3 mg/kg and 5 mg/kg. Conclusion: Buspirone 3 mg/kg and 5 mg/kg does not have any effect on blood glucose levels, while in a high dose of 10 mg/kg causes a significant transient increase in the blood glucose level.

Establishment of rat model with diabetes mellitus and concomitant periodontitis and the carotid artery lesions in the model rats

Objectives: To establish SD rat model with type 2 diabetes mellitus (DM) and concomitant chronic periodontitis (CP) and to evaluate the influence of periodontitis on the vascular lesions of type 2 diabetes rats. Methods: Totally 241 clean level SD rats were randomly divided into four groups, group A (normal control, NC, n=27), group B (DM, n=34), group C (CP, n=90) and group D (DM+CP, n=90). The rats of DM group were fed with high-fat and high-sugar diet for 8 to 10 weeks, and then were multiply injected with small dose streptozotocin under the condition of ice bath. Blood sugar levels after the injection were dynamically monitored at 72 h, 1 week, 2 weeks and 4 weeks, respectively. The CP model was established by means of ligation. Bilateral maxillary first and second molars were selected and ligated using 0.2 mm orthodontic wires binding with 4-0 surgical suture soaked with Porphyromonas gingivalis (Pg) suspension. After a period of 14 weeks, all the rats were put to death. Maxillary samples were subjected to methylene blue staining to observe alveolar bone loss. Bilateral carotid artery specimens were collected. The left carotid artery specimens were used to detect the prevalence of Pg using quantitative real-time PCR. The right carotid artery specimens were used to observe pathological changes. Results: Blood sugar levels of rats in group B and D increased and changed sharply after Streptozotocin injection with in 1 week. Symptoms of 'more drink, more food and body weight loss' appeared. The fasting blood glucose (FBG) was more than 7.8 mmol/L and (or) the random blood glucose (RBG) was more than 17.8 mmol/L. Both FBG and RBG became stable after 2 to 3 weeks. Levels of HbA1C in group B and D ([7.32±0.45]%, [9.41±0.45]%) were significantly higher than that of group A ([4.02±0.45]%) (P<0.01). Rats of group D were observed the most severe bone loss showing wider interdental space and furcation involvement. Pathological results of carotid artery tissues of group D showed the worst lesions including thinning and calcification of vessel walls, and breaking down or disappearance of elastic fibers. The prevalences of DNA of Pg in groups of A, B, C and D were 3/7, 3/7, 6/7 and 7/7, respectively. The bacteria numbers detected by quantitative real-time PCR in groups C and D were significantly higher than that of groups A and B (P<0.01). Conclusions: Rat model of type 2 DM with periodontitis was successfully established in the present study. Carotid artery specimens from DM+CP model rats showed typical vascular lesions such as calcification and fiber disorders. Pg was found in all carotid specimens and the highest bacteria numbers were detected in the composite model rats. The Pg might play a role in the progress of diabetes vascular lesions.

Changes in blood sugar levels of rats experimentally infected with Trypanosoma brucei and treated with imidocarb dipropionate and diminazene aceturate

Objective: To determine the effect of Trypanosoma brucei (T. brucei) on blood sugar level of infected rats. Methods: The experiment was done with 42 albino rats grouped into 3 groups of 14 members each. Group A was uninfected (control group), Group B was infected with T. brucei and treated with diminazene aceturate, and Group C was infected with T. brucei and treated with imidocarb dipropionate. Blood samples were collected from the media canthus of the experimental rats on Days 0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10 for the assessment of change in blood sugar levels. The blood sugar levels were determined with a glucometer (Accu-chek active serial No. GN: 10023338). Results: By 4 to 5 days post infection, there was a significant increase (P 0.05) was observed in the groups when compared with the control group till Day 12 of the experiment. Conclusions: T. brucei caused a significant increase in blood sugar of infected rats.

A Total Triterpene Glycosides Preparation from Zygophyllum Oxianum as a Potential Hypoglycemic Agent

Extraction of a total triterpene glycosides preparation from Zygophyllum oxianum and its influence on blood sugar levels in rats with alloxan hyperglycemia and alloxan diabetes are addressed. This preparation had marked hypoglycemic actions on prophylactic and therapeutic administration. The mechanism of action is different from that of the known drug used for the treatment of diabetes Maninil.

Efek Antidiabetes dan Identifikasi Senyawa Dominan Fraksi Kloroform Herba Ciplukan (Physalis angulata L.)

Antidiabetic activity of ciplukan (Physalis angulata L.) herb has been widely observed, as an extracts and infusions, proven to reduce blood sugar levels in rats or mice induced by alloxan. The research objective was to evaluate the antidiabetic effect and identify the content of the chloroform fraction ciplukan herb eluated with methanol-ammonia. An- tidiabetic effects testing conducted using 30 male white mice (Mus musculus) ddY strain were divided into 6 groups, each consisting of 5 mice. K-1 is a negative control induced by alloxan, K-2, K-3 and K-4 induced by alloxan and treated with the test substance dose of 50 mg/kg bw/day, 100 mg/ kg bw/day, 200 mg/kg bw/day, K-5 is a positive control, induced by alloxan and treated with metformin dose of 65 mg/kg bw, K-6 as normal controls . Each mouse blood samples taken on day 7 and day 14, to test their blood sugar levels. Data were analyzed using one-way anova and multiple differences test. Identification of the content of the chloroform fraction eluated with methanol-ammonia, carried out by gas chroma- tography mass spectrometry (GC-MS). The results showed that all three doses showed a decrease in blood sugar levels significantly at day 7 , but the decline has not reach normal levels. Blood sugar levels drop significantly and the decline has reached normal occurred on day 14. Dominant content of the chloroform fraction eluated with methanol-ammonia is a class of unsaturated fatty acid chain length is Hexanoic acid, C16H1202, hexadecanoic acid methyl ester, C17H3402, 9-octadecenoic acid methyl ester, C19H3602, Oleic acid butyl ester, C22H4202, 9-octadecenoic acid, C19H3602, Octadecanoic acid, C18H3602, 1,2-Benzendicarboxylic acid, C8H604, and Aplysterylacetate, C31H5202. Another result is that Nordextromethorphan alkaloid compound, Cl 7H23NO. The conclusion is chloro- form fraction of ciplukan herb has antidiabetic effects and has a class of compounds con- tent of unsaturated fatty acids, Aplysterylacetate and alkaloid Nordextromethorphan.

Single Periocular Injection of Celecoxib-PLGA Microparticles Inhibits Diabetes-Induced Elevations in Retinal PGE2, VEGF, and Vascular Leakage

To determine whether celecoxib inhibits VEGF secretion from ARPE-19 cells and to investigate further the safety and effectiveness of periocular celecoxib-poly (lactide-co-glycolide; PLGA) microparticles in inhibiting elevations in retinal PGE(2), VEGF, and blood-tissue barrier leakage at the end of 60 days in a streptozotocin diabetic rat model. VEGF mRNA and protein expression in ARPE-19 cells was evaluated in the presence of 0 to 10 microM celecoxib, and cytotoxicity of celecoxib on ARPE-19 and RF6A cells was evaluated over a 0- to 100-microM concentration range. Celecoxib-PLGA microparticles were prepared by a modified solvent evaporation technique, sterilized by 25 kGy of gamma-irradiation, and characterized for size, zeta potential, drug loading, and in vitro release. Normal and streptozotocin-diabetic male Sprague-Dawley rats were divided into five groups: normal, diabetic, diabetic+placebo, normal+celecoxib, and diabetic+celecoxib. Phosphate-buffered saline (PBS) containing celecoxib-PLGA microparticles, placebo PLGA microparticles, or plain PBS in one eye was injected into the posterior subconjunctival (periocular) space in rats under anesthesia. Sixty days after administration, the animals were killed, and retinal PGE2 secretion, VEGF protein, and blood-retinal barrier leakage were estimated. Blood cell counts, blood chemistry and histology were used to assess the safety of the microparticulate system. Celecoxib (up to 25 microM) did not cause significant cytotoxicity in ARPE-19 or RF6A cells. Nanomolar concentrations of celecoxib reduced VEGF mRNA and VEGF protein secretion. Celecoxib-PLGA microparticles (diameter: 1140 +/- 15 nm), containing 14.93% +/- 0.21% of celecoxib sustained in vitro drug release and in vivo drug levels in the retina for 60 days. Diabetes elevated PGE2 secretion, VEGF protein, the vitreous-plasma protein ratio, and blood-retinal barrier leakage by 3-, 1.7-, 3.1-, and 2.7-fold, and celecoxib-PLGA microparticles significantly reduced these elevations by 40%, 50%, 40%, and 50%, respectively. Neither the placebo-treated eyes nor the contralateral eyes in celecoxib-PLGA microparticle-treated rats showed significant effects. Celecoxib-PLGA or placebo-PLGA particles had no effect on the body weight or blood sugar level of rats. The celecoxib-PLGA microparticles did not cause any changes in blood cell counts or chemistry and caused no histopathological damage to the retina or periocular tissues. Nanomolar concentrations of celecoxib can inhibit VEGF mRNA and protein expression from ARPE-19 cells. Periocular celecoxib microparticles are useful sustained drug delivery systems for inhibiting diabetes-induced elevations in PGE2, VEGF, and blood-retinal barrier leakage. The periocular celecoxib-PLGA microparticles are safe and do not cause any damage to the retina.

Effect of Nelumbo nucifera rhizome extract on blood sugar level in rats

Oral administration of the ethanolic extract of rhizomes of Nelumbo nucifera markedly reduced the blood sugar level of normal, glucose-fed hyperglycemic and streptozotocin-induced diabetic rats, when compared with control animals. The extract improved glucose tolerance and potentiated the action of exogenously injected insulin in normal rats. When compared with tolbutamide, the extract exhibited activity of 73 and 67% of that of tolbutamide in normal and diabetic rats, respectively.

ELECTRICAL STIMULATION IN RESTRICTED AREA OF ABDOMINAL SKIN INCREASED GLUCOSE LEVEL VIA THE PANCREATIC BRANCH OF THE VAGAL NERVE IN THE RAT

Electrical stimulation (5 V, 50 Hz, 10 min.) of the middle upper abdominal area (Chuin acupuncture point) increased the blood sugar level in rats anesthetized with chloralose (60 mg/kg) and urethane (0.6 g/kg). Stimulation of both sides of middle abdominal skin area also increased the blood sugar level. However, electrical stimulation of other areas of the abdominal skin or the front paw, lower leg or thigh did not alter blood sugar level. Electrical stimulation of the middle upper abdomen inhibited spontaneous firing of the vagal nerve that innervates the pancreas, and enhanced neuronal discharges elicited in those fibers by intravenous glucose injection.