Biochemical and Toxicological Studies of Aqueous Extract of Syzigium Aromaticum (L.) Merr. & Perry (Myrtaceae) in Rodents

The effects of long-term administration of boiled aqueous extract of Syzigium aromaticum (SYZ), commonly known as clove (which has been locally employed for treating gastrointestinal tract diseases and also used as food spices), on some biochemical indices, such as body weight, liver functions and blood parameters were studied in adult albino rats of both sexes. Selected doses of 300 and 700 mg kg⁻¹ were given orally through cannular to groups of animals for a period of 90 days, while the control group received distilled water throughout the duration of study via the same route. Blood samples collected after therapy and assayed for activities of some liver enzymes recorded a significant (p<0.05) and prominent effect on ALP and AST. Measurement of haematological parameters also revealed significant effects (p<0.05; p<0.001) on Hb, RBC (p<0.05), PCV (p<0.001), platelets (p<0.001) and granulocytes (p<0.001). An insignificant reduction was recorded for total WBC. The histopathological study conducted was in consonance with the results of the biochemical investigations that the aqueous extract of SYZ even at moderate doses, significantly affects body organs, their enzymes as well as the various functions. LD₅₀ for both intraperitoneal and oral routes of SYZ were 263 and 2500 mg kg⁻¹ respectively. The present work has revealed the toxicity of sub chronic administration of SYZ, which suggests that its prolonged usage must be avoided.     

Hypoglycemic Effect of Treculia Africana Decne Root Bark in Normal and Alloxan-Induced Diabetic Rats

The solvent partitioned purified fractions of the hydro-acetone root bark extract of the African breadfruit (Treculia africana Decne) were evaluated for hypoglycemic activities in normal and diabetic albino rats. Fasting blood glucose levels were estimated by the use of a glucometer at pre-determined intervals after oral administration of the test extracts/fractions. Results revealed that the test fractions have only a slight effect on blood sugar level of normal rats. On short term and chronic administration in diabetic rats however, diethyl ether-soluble (DEF) and the water-soluble (WSF) fractions significantly reduced the fasting blood sugar levels (p<0.05) at differing rates when compared with the control group of animals. The diethyl ether soluble fraction (10 mg kg⁻¹ dose level) was found to exhibit the highest activity giving 69.4% reduction in blood sugar level (at 240 hours) which was in comparable range with the reference standard glibenclamide (0.5 mg kg⁻¹) which reduced blood sugar levels by 65.8% below the initial baseline values.     

Absence of Organ Specific Toxicity in Rats Treated with Tonica, an Aqueous Herbal Haematinic Preparation

The sub-chronic toxicity of Tonica, an aqueous herbal haematinic prepared from the stem barks of Khaya senegalensis, Mitragyna stipulosa and Kigelia africana, was investigated in male Sprague-Dawley rats at 28, 280 and 560 mg kg⁻¹ day⁻¹, representing the normal human dose, 10x and 20x that dose, respectively for 6 weeks. The growth rate of animals over the period of treatment and certain serum biochemical and haematological indices as well as urinalysis and weight of selected organs at termination, were determined. Results show that the extract did not affect the weight gain of the animals with time or the mean wet weights of selected organs. Although there were slight but insignificant (p>0.05) elevations in WBC (16–27%) and PLT (8–11%) counts in Tonica-treated animals compared to controls at 10x and 20x the normal dose, most serum biochemical, haematological and urinalysis data indicated no significant differences (p>0.05) between tests and control rats. There were also no changes in the morphology of liver, kidney, lung and heart tissues as a result of Tonica treatment. These findings suggest that Tonica is safe at the dosage regimens administered to the animals in this study, and there appears to be no overt organ specific toxicity associated with it.     

Role of Wormwood (Artemisia Absinthium) Extract on Oxidative Stress in Ameliorating Lead Induced Haematotoxicity

Effects of ROS generation have been postulated to be major contributors to lead-exposure related disease. The aim of the study was to investigate the effect of aqueous extract of wormwood (Artemisia absinthium) on oxidative stress in rats protractedly exposed to lead. Aqueous extract of wormwood plant was administered orally (200 mg.kg⁻¹ body weight). Plasma vitamin C, E and non-protein thiol concentrations, red blood cells (RBC) thiobarbituric acid reactive substances, reduced glutathione levels and haemolysis test were evaluated. In addition, RBC antioxidant enzymes activities such as superoxide dismutases, catalase, glutathione peroxidase, glutathione reductase were also estimated. After 11-weeks, significant decreases of plasma vitamin C, E, non protein-thiol (NP-SH) and RBC-reduced glutathione levels were observed in Pb compared to control group (−32.9%, −57.1%, −53.1%, −33.9%, respectively); superoxide dismutase, glutathione peroxidase, uric aminolevulinic acid and haemolysis test significantly increased in Pb compared to control group (+64.3%, +40.3%, +145%, +44.3%, respectively). In our investigation, after 4-weeks of treatment all treated groups did not show any difference compared to the control group, except for glutathione peroxidase and RBC-superoxide dismutase activity (−15.7% and +16.4%, respectively). The findings of this study suggest that wormwood (Artemisia absinthium) extract restored the enzymes activities perturbed by exposure to lead, and had a protective role against lipid peroxidation     

Artocarpus Communis Forst. Root-Bark Aqueous Extract- and Streptozotocin-Induced Ultrastructural and Metabolic Changes in Hepatic Tissues of Wistar Rats

Decoctions and infusions of Artocarpus communis (Forst.) (family: Moraceae) root-bark are commonly used traditionally among the Yoruba-speaking people of Western Nigeria as folk remedies for the management, control and/or treatment of an array of human diseases, including type 2, adult-onset diabetes mellitus. Although numerous bioactive flavonoids have been isolated from the roots, stem-bark and leaves of A. communis, to the best of our knowledge, the effects of the plant''s root-bark extract on animal model of diabetes mellitus and on liver tissues have hitherto, not been reported in the biomedical literature. In view of this, the present study was undertaken to investigate the glycaemic effect of, and hepatic tissue ultrastructural, morphological and metabolic changes induced by, A. communis root-bark aqueous extract (ACE) in Wistar rats. The ultrastructural, morphological and metabolic effects of ACE have been compared with those induced by streptozotocin (STZ) in rat experimental paradigms. Four groups (A, B, C and D) of Wistar rats, each group containing 10 rats, were used. Diabetes mellitus was induced in the diabetic groups B and C animals by intraperitoneal injections of STZ (75 mg/kg body weight), while group A rats received A. communis root-bark aqueous extract (ACE, 100 mg/kg body weight, i.p.) alone. Control group D rats received distilled water in quantities equivalent to the volume of ACE administered intraperitoneally. The rats in group C were additionally treated with ACE (100 mg/kg body weight i. p.) daily from day 3 to day 10 after STZ treatment. Hepatic glucokinase, hexokinase, glutamate dehydrogenase, succinate dehydrogenase, β-hydroxybutyrate dehydrogenase, serum insulin and blood glucose levels of the animals were measured and recorded before and after ACE, STZ and STZ+ACE treatments. Hepatic tissues were also processed for transmission electron microscopy. Electron microscopic examinations showed toxic, deleterious alterations in the ultrastructures of groups A, B and C hepatic cells, the most prominent deleterious effects being on the hepatocytes. Ultrastructural changes observed within the hepatocytes of groups A, B and C rats include disrupted mitochondria with increase in lipid droplets, extensive hepatocellular vacuolation, scanty rough endoplasmic reticulum (RER) and ribosomes. Large glycogen clusters were also noticed displacing the mitochondria and RER in group A rats. Group A rats also developed significant hyperglycemia (p<0.05) immediately after ACE administration, while groups B and C rats developed hyperglycemia 24 hours after STZ treatment. When compared with the control group D rats, the activities of all the three subsystems were disrupted, leading to overall inhibition of oxidative phosphorylation of the liver mitochondria in groups A, B and C rats, but remain normal in the untreated group D control rats. The findings of the present study indicate that A. communis root-bark aqueous extract induces hyperglycaemia in the experimental animal model used, and that the plant''s extract disrupts the ultrastructural characteristics and architecture of hepatocytes as well as oxidative energy metabolism.     

Evaluation of the Chemical Composition of Dacryodes Edulis and Raphia Hookeri Mann and Wendl Exudates used in Herbal Medicine in South Eastern Nigeria

The phytochemical contents and medicinal values of Dacroydes edulis and Raphia hookeri exudates were investigated. Phytochemical screening of the plant showed that they contain the presence of bioactive compounds comprising saponins (2.08–3.98mg 100g⁻¹), alkaloids (0.28–0.49 mg 100g⁻¹), tannins (0.47–0.72 mg 100g⁻¹), flavonoids (0.26–0.39 mg 100g⁻¹), and phenolic compounds (0.01–0.05 mg 100g⁻¹). The carbohydrates, lipids and protein content were 77.42–78.90%, 2.02–4.185% and 16.63–18.38% respectively. The exudates are a good source of water soluble vitamins; ascorbic acid (7.04–26.40 mg 100g⁻¹), niacin (3.12–4.00 mg 100g⁻¹), riboflavin (0.14–0.54 mg 100g⁻¹) and thiamine (0.15–0.22 mg 100g⁻¹),). Both plants exudates are good sources of minerals such as Ca, Mg, P, Fe, Zn, Cu and Mn while Cr and Co were trace. These results indicate that exudates can be potential sources of feedstock for the pharmaceutical industry.     

Antidiabetic effect of kolaviron,a biflavonoid complex isolated from Garcinia kola seeds,in Wistar rats

Background

Hypoglycaemic effect of kolaviron (KV), (biflavonoid from Garcinia kola) in streptozotocin (STZ)-diabetic rats has been established.

Objectives

To evaluate the possible protective effects of KV on cardiac, renal and hepatic tissues of STZ-diabetic rats.

Methods

This study consists of four groups of 6 rats each. Groups one and two contained non-diabetic and untreated-diabetic rats, respectively. Groups three and four were made up of KV- and glibenclamide (GB) - treated diabetic rats, respectively.

Results

STZ-intoxication caused a significant (p<0.05) increase in the relative weight of liver in diabetic rats. STZ-diabetic rats had significant increase (p<0.05) in the levels of fasting blood glucose (FBG), á-amylase and HbA_1c. A marked and significant (p<0.05) increase in the levels of cardiac, renal and liver marker indices such as serum creatine kinase, lactate dehydrogenase, creatinine, urea and alanine aminotransferase were observed in untreated diabetic rats. Also, untreated diabetic rats had significantly (p<0.05) elevated urinary glucose and protein and, lowered creatinine clearance. In KV- and GB- treated groups, the levels of FBG, á-amylase and HbA_1c were significantly (p<0.05) reduced, while treatment with KV significantly (p<0.05) attenuated the cardiac, renal and liver marker indices.

Conclusion

KV offered significant antidiabetic and tissues protective effects in the rats.     

Biochemical and immunohistochemical changes in delta-9-tetrahydrocannabinol-treated type 2 diabetic rats

The regulation of glucose, lipid metabolism and immunoreactivities of insulin and glucagon peptides by delta-9-tetrahydrocannabinol (Δ⁹-THC) in diabetes were examined in an experimental rat model. Male Sprague-Dawley rats were divided into four groups: (1) control, (2) Δ⁹-THC treated, (3) diabetic, and (4) diabetic + Δ⁹-THC. The type 2 diabetic rat model was established by intraperitoneal (i.p.) injection of nicotinamide (85 mg/kg body weight) followed after 15 min by i.p. injection of streptozotocin (STZ) at 65 mg/kg of body weight. Δ⁹-THC and Δ⁹-THC treated diabetic groups received 3 mg/kg/day of Δ⁹-THC for 7 days. The immunolocalization of insulin and glucagon peptides was investigated in the pancreas using a streptavidin–biotin–peroxidase technique. High density lipoprotein cholesterol (HDL), low density lipoprotein cholesterol (LDL), very low density lipoprotein cholesterol (VLDL), triglycerides (TG), total cholesterol (TC) and total protein (TP) levels were measured in serum. Total islet area percent of insulin immunoreactive cells slightly changed in diabetic + Δ⁹-THC rats compared to diabetic animals. However, the area percent of glucagon immunoreactive cells showed a decrease in diabetic + Δ⁹-THC rats compared to that of diabetic animals alone. Serum TC, HDL and LDL levels of diabetes + Δ⁹-THC group showed a decrease compared to the diabetic group. These results indicate that Δ⁹-THC may serve a protective role against hyperlipidemia and hyperglycemia in diabetic rats.     

Chlorophytum borivilianum Root Extract Maintains near Normal Blood Glucose,Insulin and Lipid Profile Levels and Prevents Oxidative Stress in the Pancreas of Streptozotocin-Induced Adult Male Diabetic Rats

The effect of C. borivilianum root on blood glucose, glycated hemoglobin (HbAIc), insulin and lipid profile levels in diabetes mellitus are not fully understood. This study therefore investigated the effect of C. borivilianum root on the above parameters and oxidative stress of the pancreas in diabetes. Methods: C. borivilianum root aqueous extract (250 and 500 mg/kg/day) was administered to streptozotocin (STZ)-induced male diabetic rats for 28 days. Body weight, blood glucose, HbA1c, insulin, lipid profile levels and glucose homeostasis indices were determined. Histopathological changes and oxidative stress parameters i.e. lipid peroxidation (LPO) and antioxidant enzymes activity levels of the pancreas were investigated. Results: C. borivilianum root extract treatment to diabetic rats maintained near normal body weight, blood glucose, HbA1c, lipid profile and insulin levels with higher HOMA-β cell functioning index, number of Islets/pancreas, number of β-cells/Islets however with lower HOMA-insulin resistance (IR) index as compared to non-treated diabetic rats. Negative correlations between serum insulin and blood glucose, HbA1c, triglyceride (TG) and total cholesterol (TC) levels were observed. C. borivilianum root extract administration prevented the increase in lipid peroxidation and the decrease in activity levels of superoxide dismutase (SOD), catalase (CAT) and glutathione peroxidase (GPx) with mild histopathological changes in the pancreas of diabetic rats. Conclusions: C. borivilianum root maintains near normal levels of these metabolites and prevented oxidative stress-induced damage to the pancreas in diabetes.     

Hepatoprotective Effect of Cymbopogon Citratus Aqueous Extract Against Hydrogen Peroxide-Induced Liver Injury in Male Rats

Background

Cymbopogon citratus (Poaceae) a tropical perennial herb plant that is widely cultivated to be eaten either fresh with food or dried in tea or soft drink has been reported to possess a number of medicinal and aromatic properties. This study aimed at evaluating the protective effects of C. citratus aqueous extract against liver injury induced by hydrogen peroxide (H₂O₂), in male rats.

Materials and Methods

Twenty-five rats were randomly divided into five different groups of five animals in each group; (1) Control. (2) Received H₂O₂ (0.5%) with drinking water. (3), and (4) received H₂O₂ and C. citratus (100 mg·kg⁻¹ b wt), vitamin C (250 mg·kg⁻¹ b wt) respectively. (5), was given C. citratus alone. The treatments were administered for 30 days. Blood samples were collected and serum was used for biochemical assay including liver enzymes activities, total protein, total bilirubin and malonaldehyde, glutathione in serum and liver homogenates. Liver was excised and routinely processed for histological examinations.

Results

C. citratus attenuated liver damage due to H₂O₂ administration as indicated by the significant reduction (p<0.05), in the elevated levels of ALT, AST, ALP, LDH, TB, and MDA in serum and liver homogenates; increase in TP and GSH levels in serum and liver homogenates; and improvement of liver histo-pathological changes. These effects of the extract were similar to that of vitamin C which used as antioxidant reference.

Conclusion

C. citratus could effectively ameliorate H₂O₂-induced oxidative stress and prevent liver injury in male rats.     

Association of FGFR2 gene polymorphisms with the risk of breast cancer in population of West Siberia

Polymorphisms within intron 2 of the FGFR2 gene have been associated with increased risk of breast cancer (BC) in European and Asian populations. The study by Easton et al reported two FGFR2 SNPs, rs2981582 and rs7895676, to be among those most strongly associated with BC risk. Statistical modeling suggested that rs7895676 was the variant responsible for the association observed in the region. In this work, we studied the association between seven FGFR2 SNPs, including rs2981582 and rs7895676, and BC risk in the Russian population of 766 case and 665 control women from Siberia, Russian Federation. In our population, allelic frequencies and the magnitude of linkage disequilibrium (LD) were different from those observed in European and Asian populations. The following three SNPs were significantly associated with BC in our study: rs7895676[C] (odds ratio (OR)=1.28 (1.12–1.43), P=1.7 × 10⁻³), rs2981582[T] (OR=1.46 (1.30–1.62), P=2 × 10⁻⁶) and rs3135718[G] (OR=1.43 (1.27–1.58), P=6 × 10⁻⁶). The latter two SNPs were in strong (r²=0.95) LD in our sample. Maximum likelihood analysis showed that the model, including rs7895676, only explains that the association is significantly (P<0.001) worse than any of the models, including either rs2981582 or rs3135718. Thus, in addition to the confirmation of association of FGFR2 with the BC risk in this new population, our study has suggested that rs7895676 is not likely to represent the causative variant.     

Evaluation of the Antioxidant Effects of Ziziphus Mauritiana Lam. Leaf Extracts Against Chronic Ethanol-Induced Hepatotoxicity in Rat Liver

Chronic alcohol ingestion is known to increase the generation of reactive oxygen species (ROS), thereby leading to liver damage. Antioxidant enzymes act individually or in combination to reduce or counter the effect of these ROS. Chronic administration of alcohol at (40% v/v, 1ml/100g), for 6 weeks showed a significant (p<0.05) elevated levels of alanine aminotransferase (ALT), aspartate aminotransferase (AST), alkaline phosphatase (ALP), and total bilirubin (TB). There was also a significant (p<0.05) decreased levels of catalase, glutathione peroxidase, glutathione reductase and superoxide dismutase compared to control rats. Pre-treatment of rats with 200, 400 mg/kg body weight of aqueous leaf extract of Ziziphus mauritiana or 100 mg/kg silymarin resulted in a significant (p<0.05) decreased levels of ALT, AST, ALP, and TB with levels of catalase, glutathione peroxidase, glutathione reductase and superoxide dismutase showing a significant (p<0.05) increase compared to group administered alcohol only. Histopathology of rat liver administered with alcohol only resulted in severe necrosis, mononuclear cell aggregation and fatty degeneration in the central and mid zonal areas which was a characteristic of a damaged liver. Pre-treatment with the aqueous extract of Ziziphus mauritiana or silymarin reduced the morphological changes that are associated with chronic alcohol administration. The presence of tannins, saponins and phenolic compounds observed in the plant extract could be responsible for the observed effects of decreasing the levels of injured tissue marker and lipid peroxidation.     

Interleukin‐17A deficiency ameliorates streptozotocin‐induced diabetes

Interleukin-17 (IL-17) is a cytokine with critical functions in multiple autoimmune diseases. However, its roles in type I diabetes and the underlying mechanisms remain to be fully elucidated. In the current study, we investigated the impact of IL-17 deficiency on streptozotocin (STZ) -induced diabetes. Il-17^−/− mice exhibited attenuated hyperglycaemia and insulitis after STZ treatment compared with control mice. The Il-17^−/− mice had fewer CD8⁺ cells infiltrating the pancreas than wild-type controls after STZ injection. Wild-type mice showed increased percentage and number of splenic CD8⁺ cells and decreased Gr1⁺ CD11b⁺ myeloid-derived suppressor cells (MDSC) after STZ treatment, but Il-17^−/− mice maintained the percentages and numbers of splenic CD8⁺ cells and MDSC, suggesting that IL-17 is implicated in STZ-induced cellular immune responses in the spleen. We further purified the MDSC from spleens of STZ-treated mice. Il-17^−/− MDSC showed increased ability to suppress CD8⁺ cell proliferation in vitro compared with wild-type MDSC. Transfer of MDSC to diabetic mice showed that MDSC from Il-17^−/− mice could ameliorate hyperglycaemia. Moreover, recipients with MDSC from Il-17^−/− mice had a decreased percentage of CD8⁺ cell in the spleen compared with recipients with MDSC from wild-type mice. These data suggest that IL-17 is required in splenic MDSC function after STZ delivery. In summary, our study has revealed a pathogenic role of IL-17 in an STZ-induced diabetes model with important implications for our understanding of IL-17 function in autoimmune diseases.     

Anti-Nociceptive and Anti-Inflammatory Effects of a Nigerian Polyherbal Tonic Tea (PHT) Extract in Rodents

The study investigated the anti-nociceptive and anti-inflammatory properties of a Nigerian Polyherbal Health Tonic tea aqueous extract (PHT) in rodents of both sexes. 100 – 500 mg kg⁻¹ of the aqueous extract was administered via the intra-peritoneal (i.p.) and oral (p.o.) routes to 5 groups of mice using tail immersion, tail clip, formalin and acetic acid-induced writhing tests of experimental nociceptive models. Each of the models showed that PHT possesses a significant (p<0.05) anti-nociceptive effects which were peripherally and centrally mediated as both the early and late phases of pain significantly (p<0.05) were inhibited. However, the peripherally mediated analgesic effect of PHT, although similar to that of aspirin but was found to be more potent than aspirin. In assessing its anti-inflammatory potentials, 300 – 1340 mg kg⁻¹ PHT was also administered via oral and intraperitoneal routes, which, significantly (p<0.05) reduced the volume of carrageenan-induced oedema. Although, PHT administered via i.p. route was more effective than the oral but there was barely any difference between the percentage inhibition of oedema volume at both 600 and 1340 mg kg⁻¹ given orally. PHT anti-inflammatory effect was elucidated to be significantly (p<0.05) mediated via histaminergic, serotonergic, bradykinin and prostaglandin inhibition. PHT was also shown to be more protective than acetylsalicylic acid (ASA) in the castor oil-induced diarrhea model, which suggests the involvement of other mechanisms. Thus, lending supports to its folkloric use in pain and swelling management.     

Protective Effect of Quercetin on the Morphology of Pancreatic ��-Cells of Streptozotocin-Treated Diabetic Rats

This study was undertaken to investigate the protective effects of quercetin (QCT) on the morphology of pancreatic β-cells against diabetes mellitus and oxidative stress experimentally-induced by streptozotocin (STZ) treatment in Wistar rats. Fifty male and female Wistar rats (200–250 g) were randomly divided into three experimental groups (i. e., control, STZ-treated, and STZ + Quercetin-treated groups). Diabetes was induced in the diabetic groups (B and C) of animals, by a single intraperitoneal injection of STZ (75 mg/kg), while each of the rats in the ‘control’ group received equal volume of citrate buffer (pH 6.3) solution intraperitoneally. In group C rats, quercetin (QCT, 25 mg/kg/day i. p.) was injected daily for 3 days prior to STZ treatment, and QCT administration continued until the end of the study period (30 days). Diabetes mellitus was confirmed by using Bayer''s Glucometer Elite® and compatible blood glucose test strips. The rats were sacrificed serially until the end of the study period (after 30 days). The pancreases of the sacrificed rats were excised and randomly processed for histological staining and biochemical assays for antioxidant enzymes [such as glutathione peroxidase (GSHPx), superoxide dismutase (SOD), catalase (CAT), malondialdehyde (MDA) and serum nitric oxide (NO)]. In the diabetic state, pancreatic β-cells of STZ-treated group B rats histologically demonstrated an early chromatin aggregation, cytoplasmic vesiculation in the central β-cells, nuclear shrinkage, and lysis of β-cells with distortion of granules. The morphology of QCT-treated rats'' pancreases showed viable cellularity with distinct β-cell mass. STZ treatment significantly decreased (p<0.05) GSHPx, SOD, CAT and pancreatic insulin content. However, STZ treatment increased blood glucose concentrations, MDA and serum NO. The QCT-treated group of animals showed a significant decrease (p<0.05) in elevated blood glucose, MDA and NO. Furthermore, QCT treatment significantly increased (p<0.05) antioxidant enzymes'' activities, as well as pancreatic insulin contents. Quercetin (QCT) treatment protected and preserved pancreatic β-cell architecture and integrity. In conclusion, the findings of the present experimental animal study indicate that QCT treatment has beneficial effects on pancreatic tissues subjected to STZ-induced oxidative stress by directly quenching lipid peroxides and indirectly enhancing production of endogenous antioxidants.     

Qualitative Phytochemical Screening and In Vitro Antimicrobial Effects of Methanol Stem Bark Extract of Ficus Thonningii (Moraceae)

The methanolic stem bark extract of Ficus thonningii (Moraceae) was subjected to preliminary phytochemical screening and in vitro antimicrobial tests. The phytochemical tests was carried out using standard methods of analysis and these investigations revealed the presence of alkaloids, anthraquinones, carbohydrates, flavonoids, saponins and tannins. The antimicrobial activity of the plant extract was assayed using the agar plate disc diffusion and nutrient broth dilution techniques. Test micro organisms were: Escherichia coli, Klebsiella spp, Pseudomonas aeruginosa, Salmonella typhi (Gram-negative), Staphylococcus aureus and Streptococcus spp. (Gram-positive). The extracts inhibited the growth of all the test organisms at different concentrations especially against Pseudomonas aeruginosa and Streptococcus spp. which had mean inhibition zone of 33.33±7.33 mm and 32.33±2.51 mm respectively. The results showed the MIC of 10 mg ml⁻¹ against pseudomonas and 1.25 against remaining organisms tested. The MBC against Staphylococcus aureus was 2.5 mg ml⁻¹ and that of Streptococcus spp. was found to be 0.625mg ml⁻¹. The extracts showed varied inhibitory activity against the organisms studied.     

Analgesic and Antipyretic Activities of Drymaria Cordata (Linn.) Willd (Caryophyllaceae) Extract

Drymaria cordata (Linn.) Willd (Caryophyllaceae) is an herbaceous plant widely used in traditional African medicine (TAM) for the treatment of diverse ailments including painful and febrile conditions. This study was conducted to investigate the analgesic and antipyretic properties of the whole plant extract of D. cordata. The acetic acid-induced writhing, formalin, and tail clip tests were used to evaluate analgesic activity while the 2,4-dinitrophenol (DNP)-, d-amphetamine-, and yeast-induced hyperthermia tests were used to investigate antipyretic activity in rodents. D. cordata (100, 200, and 400 mg kg⁻¹, p.o) produced significant (p<0.05) analgesic activity in the mouse writhing, formalin (second phase), and tail clip tests. The effects of D. cordata were generally comparable to those of acetylsalicylic acid (ASA, 100 mg kg⁻¹, p.o) and morphine (2 mg kg⁻¹, s.c). Also, D. cordata produced significant (p<0.05) dose-dependent inhibition of temperature elevation in the 2,4-DNP and yeast-induced hyperthermia models with peak effects produced at the dose of 400 mg kg⁻¹. The effect at this dose was comparable to that of ASA in the two models. In the d-amphetamine method, D. cordata produced significant (p<0.05) dose- and time-dependent reduction of temperature elevation with peak effect produced at the dose of 200 mg kg⁻¹. The effect of the extract at this dose was greater than that of ASA. The results obtained in this study demonstrate that the aqueous whole plant extract of Drymaria cordata possesses analgesic and antipyretic properties mediated through peripheral and central mechanisms.     

Gynura procumbens Merr. decreases blood pressure in rats by vasodilatation via inhibition of calcium channels

INTRODUCTION:

Gynura procumbens has been shown to decrease blood pressure via inhibition of the angiotensin‐converting enzyme. However, other mechanisms that may contribute to the hypotensive effect have not been studied.

OBJECTIVES:

To investigate the cardiovascular effects of a butanolic fraction of Gynura procumbens in rats.

METHODS:

Anaesthetized rats were given intravenous bolus injections of butanolic fraction at doses of 2.5–20 mg/kg in vivo. The effect of butanolic fraction on vascular reactivity was recorded in isolated rat aortic rings in vitro.

RESULTS:

Intravenous administrations of butanolic fraction elicited significant (p<0.001) and dose‐dependent decreases in the mean arterial pressure. However, a significant (p<0.05) decrease in the heart rate was observed only at the higher doses (10 and 20 mg/kg). In isolated preparations of rat aortic rings, phenylephrine (1×10^‐6 M)‐ or potassium chloride (8×10^‐2 M)‐precontracted endothelium‐intact and ‐denuded tissue; butanolic fraction (1×10^‐6–1×10^‐1 g/ml) induced similar concentration‐dependent relaxation of the vessels. In the presence of 2.5×10^‐3 and 5.0×10^‐3 g/ml butanolic fraction, the contractions induced by phenylephrine (1×10^‐9–3×10^‐5 M) and potassium chloride (1×10^‐2–8×10^‐2 M) were significantly antagonized. The calcium‐induced vasocontractions (1×10^‐4–1×10^‐2 M) were antagonized by butanolic fraction concentration‐dependently in calcium‐free and high potassium (6×10^‐2 M) medium, as well as in calcium‐ and potassium‐free medium containing 1×10^‐6 M phenylephrine. However, the contractions induced by noradrenaline (1×10^‐6 M) and caffeine (4.5×10^‐2 M) were not affected by butanolic fraction.

CONCLUSION:

Butanolic fraction contains putative hypotensive compounds that appear to inhibit calcium influx via receptor‐operated and/or voltage‐dependent calcium channels to cause vasodilation and a consequent fall in blood pressure.     

No association of PTGDR -441C/T polymorphism with asthma in a North Indian population

Background: Asthma is the most prevalent disease in India according to the national survey conducted by NFHS 2 in 1998–399. Prostaglandin D2 (PGD2) is a bronchoconstriction inducing metabolite of arachidonic acid in the mast cells, which is produced on exposure to allergens and acts as a ligand for the Prostaglandin D2 Receptor (PTGDR). Polymorphisms in the PTGDR gene have been suggested to be involved in the mechanism of asthma. Objective: This is the first study conducted in India, investigating the role of PTGDR −441C/T promoter polymorphism in asthma pathogenesis. Methods: A case-control study was performed with a total of 992 subjects, including 410 adult asthmatics and 582 healthy controls from regions of North India. The PTGDR−441C/T polymorphism was genotyped by Tetra-Primer Amplification Refractory Mutation System Polymerase Chain Reaction (Tetra-Primer ARMS PCR). Results: Statistical analysis of the results between asthma cases and controls for the PTGDR −441C/T polymorphism showed Chi² (χ²) = 0.29, OR = 0.95, 95% CI (0.70–1.15) and p = 0.599. Neither the genotypic nor the allelic frequencies observed for the PTGDR −441C/T polymorphism, were significantly associated with asthma or asthma phenotypes. Conclusions: The PTGDR −441C/T polymorphism is not associated with asthma or its phenotypes in the studied North Indian population.