Bupivacaine hydrochloride complexation with some α- and β-cyclodextrins studied by potentiometry with membrane electrodes

Evaluation of the effects of bupivacaine combined with sugammadex on the duration of the nociceptive blockade in sciatic nerve blocks: a controlled, double-blind animal study

BACKGROUND

Animal and other experimental studies have demonstrated increased block time and quality when α- and β-cyclodextrin drugs are combined with local anesthetics. However, to our knowledge, no study has utilized γ-cyclodextrins in such a combination. In the present study, we used an animal model to evaluate the effects of different doses of the combined administration of γ-cyclodextrin (sugammadex) and bupivacaine on the duration of sciatic nerve blocks in rats.

METHODS

Sciatic nerve blocks were performed with a 0.20 ml mixture in all groups. For the non-experimental groups, this mixture consisted of 0.2 ml saline (Sham group), 0.2 ml sugammadex (Group S), or 0.16 ml bupivacaine 0.5% and 0.04 ml saline (Group B). For the experimental groups, 0.16 ml bupivacaine 0.5% was administered along with 0.01 ml sugammadex and 0.03 ml saline (Group BS1), 0.02 ml sugammadex and 0.02 ml saline (Group BS2), or 0.04 ml sugammadex (Group BS4). Proprioception, nociception, and motor function were evaluated until the sciatic block was completely reversed.

RESULTS

Motor, proprioceptive, and nociceptive blockades occurred within 5 min in all experimental groups. In Group BS4, the duration of the motor, proprioceptive, and nociceptive blockades was significantly increased compared with the other experimental groups. However, in Groups BS1 and BS2, only the duration of the nociceptive blockade was significantly increased.

CONCLUSIONS

The combined administration of sugammadex and bupivacaine for sciatic nerve blocks in rats led to a significant increase in the duration of motor, proprioceptive, and nociceptive blockades.

Physicochemical characterization and cytotoxicity of articaine-2-hydroxypropyl-β-cyclodextrin inclusion complex

Articaine (ATC) is one of the most widely used local anesthetics in dentistry. Despite its safety, local toxicity has been reported. This study aimed to develop an ATC-2- hydroxypropyl-β-cyclodextrin inclusion complex (ATC HPβCD) and to assess its toxicity in vitro. The inclusion complex was performed by solubilization, followed by a fluorimetric and job plot assay to determine the complex stoichiometry. Scanning electron microscopy, DOSY- 1 H-NMR, differential scanning calorimetry (DSC), and sustained release kinetics were used to confirm the inclusion complex formation. In vitro cytotoxicity was analyzed by MTT assay and immunofluorescence in HGF cells. Fluorimetric and job plot assay determined the inclusion complex stoichiometry (ATC:HPβCD = 1:1) and complex formation time (400 min), as indicated by a strong host/guest interaction (Ka = 117.8 M - 1), complexed fraction (f = 41.4%), and different ATC and ATC HPβCD melting points (172 °C e 235 °C, respectively). The mean of cell viability was 31.87% and 63.17% for 20-mM ATC and 20-mM ATC HPβCD, respectively. Moreover, remarkable cell toxicity was observed with free ATC by immunofluorescence. These results indicate the ATC HPβCD complex could be used to improve the safety of ATC. Further research are needed to establish the anesthetic safety and effectiveness in vivo .

Some Biological Properties of Curcumin: A Review

Curcumin (diferuloyl methane), a small-molecular weight compound isolated from the roots of Curcuma longa L. (family Zingiberaceae), has been used traditionally for centuries in Asia for medicinal, culinary and other purposes. A large number of in vitro and in vivo studies in both animals and man have indicated that curcumin has strong antioxidant, anti-carcinogenic, anti-inflammatory, anti-angiogenic, antispasmodic, antimicrobial, anti-parasitic and other activities. The mechanisms of some of these actions have recently been intensively investigated. Curcumin inhibits the promotion/ progression stage of carcinogenesis by induction of apoptosis and the arrest of cancer cells in the S, G2/M cell cycle phase. The compound inhibits the activity of growth factor receptors. The anti-inflammatory properties of curcumin are mediated through their effects on cytokines, lipid mediators, eicosanoids and proteolytic enzymes. Curcumin scavenges the superoxide radical, hydrogen peroxide and nitric oxide, and inhibits lipid peroxidation. These actions may be the basis for many of its pharmacological and therapeutic properties.

Curcumin is a nutraceutical of low toxicity, which has been used successfully in a number of medical conditions that include cataracts, cystic fibrosis, and prostate and colon cancers.

Biochemical and Histopathological Evaluation of the Radioprotective Effects of Melatonin Against Gamma Ray-Induced Skin Damage

BACKGROUND

Radiotherapy is one of the treatment methods for cancers using ionizing radiations. About 70% of cancer patients undergo radiotherapy. Radiation effect on the skin is one of the main complications of radiotherapy and dose limiting factor. To ameliorate this complication, we used melatonin as a radioprotective agent due to its antioxidant and anti-inflammatory effects, free radical scavenging, improving overall survival after irradiation as well as minimizing the degree of DNA damage and frequency of chromosomal abrasions.

METHODS

Sixty male Wistar rats were randomly assigned to 4 groups: control (C), melatonin (M), radiation (R) and melatonin + radiation (MR). A single dose of 30 Gy gamma radiation was exposed to the right hind legs of the rats while 40 mg/ml of melatonin was administered 30 minutes before irradiation and 2 mg/ml once daily in the afternoon for one month till the date of rat's sacrifice. Five rats from each group were sacrificed 4, 12 and 20 weeks after irradiation. Afterwards, their exposed skin tissues were examined histologically and biochemically.

RESULTS

In biochemical analysis, we found that malondialdehyde (MDA) levels significantly increased in R group and decreased significantly in M and MR groups after 4, 12, and 20 weeks, whereas catalase (CAT) and superoxide dismutase (SOD) activities decreased in the R group and increased in M and MR groups during the same time periods compared with the C group (p<0.05). Histopathological examination found there were statistically significant differences between R group compared with the C and M groups for the three different time periods (p<0.005, p<0.004 and p<0.004) respectively, while R group differed significantly with MR group (p<0.013). No significant differences were observed between C and M compared with MR group (p>0.05) at 4 and 20 weeks except for inflammation and hair follicle atrophy, while there were significant effects at 12 weeks (p<0.05).

CONCLUSION

Melatonin can be successfully used for the prevention and treatment of radiation-induced skin injury. We recommend the use of melatonin in optimal and safe doses. These doses should be administered over a long period of time for effective radioprotection and amelioration of skin damages as well as improving the therapeutic ratio of radiotherapy.

Pulmonary administration of curcumin inhibits B16F10 melanoma lung metastasis and invasion in mice

PURPOSE

Curcumin is expected to have beneficial effects including an anti-cancer effect. However, its lower bioavailability is a critical concern and limits the utility of curcumin in clinical practice. In this study, we investigated whether transpulmonary delivery of curcumin is pharmacologically effective along with improving its bioavailability in mice with lung metastasis.

METHODS

C57BL/6J mice were injected with B16F10 melanoma cells via their tail vein and given curcumin by pulmonary administration every other day. The lung tissue of the vehicle-treated mice on day 17 was covered by nodules of metastatic melanoma.

RESULTS

Pulmonary curcumin administration significantly and dose-dependently protected the lung metastasis of melanoma. The phosphorylation of JNK (c-Jun NH2 terminal kinase) and HLJ1 expression levels in the lung metastatic nodules of the melanoma were significantly increased by pulmonary curcumin administration. The anti-metastatic effect of curcumin was blunted in mice injected with HLJ1 knocked-down B16F10 melanoma. Systemic bioavailability after pulmonary administration was 61-times higher than after oral administration. Additionally, the curcumin concentration in the lung tissue was sustained to a high level until 24 h after pulmonary administration.

CONCLUSIONS

This study showed the usefulness of curcumin to suppress lung metastasis of melanoma by pulmonary administration, a method that may overcome the low-bioavailability of curcumin.

The protective effect of melatonin in lungs of newborn rats exposed to maternal nicotine

We investigated possible healing effects of melatonin (MEL) on biochemical and histological changes in the lungs of rat offspring caused by exposure to nicotine (NT) in utero. Pregnant rats were divided randomly into five groups. The SP group was treated with physiological saline. The EA group was treated with ethyl alcohol. The MEL group was treated with MEL. The NT group was treated with NT. The NT + MEL group was treated with NT and MEL. At the end of the study, the biochemistry and histopathology of lung tissue of the offspring were examined. Reduced alveolar development and increased numbers of alveolar macrophages and mast cells were observed in the NT group compared to the SP, EA and MEL groups. We also found increased malondialdehyde (MDA) levels and decreased total glutathione (GSH) levels in the NT group. Application of MEL ameliorated the histological and biochemical damage caused by NT. The number of alveoli was greater in the NT + MEL group than in the NT group. Also, the increased numbers of alveolar macrophages and mast cells resulting from exposure to NT were decreased following MEL treatment. We found that MEL caused a significant decrease in the level of MDA. Maternal exposure to NT caused significant structural and biochemical changes in the lungs of the offspring and administration of MEL ameliorated the changes.

Curcumin and its synthetic analogue dimethoxycurcumin differentially modulates antioxidant status of normal human peripheral blood mononuclear cells

Curcumin is a polyphenol derived from the herb Curcuma longa, which has been extensively studied in terms of its antitumour, antioxidant, and chemopreventive activity as well as various other effects. In the present work we compared curcumin with its synthetic analogue dimethoxycurcumin (dimc) in terms of its antioxidant enzyme-modulating effects in human peripheral blood mononuclear cells (PBMC). We found that these compounds modulate antioxidant enzymes differentially. Both curcumin and dimethoxycurcumin effected a decrease in lipid peroxidation status in PBMC, however, curcumin had better activity in this regard. An increase in the activity of catalase was seen in the case of curcumin-treated PBMC, whereas dimc increased catalase activity significantly to almost twofold level. Real time-polymerase chain reaction (RT-PCR) analysis revealed significant up-regulation of catalase at mRNA level post treatment with curcumin as well as dimc, however, dimc had better activity in this regard. Glutathione reductase (GR) activity and reduced glutathione levels increased in the case of peripheral blood mononuclear cells (PBMC) treated with curcumin, however, the trend was reversed with dimethoxycurcumin where, both glutathione reductase activity and reduced glutathione levels were significantly reduced. RT-PCR analysis of glutathione reductase mRNA levels showed decrease in mRNA levels post treatment with dimethoxycurcumin (dimc) further corroborating GR enzyme assay results, however, we could not obtain significant result post curcumin treatment. NFkB reporter assay and western blot analysis of nuclear as well as cytosolic fractions of NFkB revealed that curcumin inhibits NFkB activation whereas inhibition was much less with dimc. It has been reported that curcumin and dimc exerts differential cytotoxicity in normal and tumour cells and the reason for this had been attributed to the differential uptake of these compounds by normal cells and tumour cells. Based on our results we propose that differential modulation of antioxidant enzymes via NFkB pathway could be the reason behind differential cytotoxicity of dimc as well as curcumin in normal cells and tumour cells in addition to differential uptake of these compounds as reported previously.

Synergistic protective effect of folic acid and vitamin B12 against nicotine-induced oxidative stress and apoptosis in pancreatic islets of the rat

CONTEXT

Nicotine is an abundant and most significant component of cigarette smoke. Epidemiological evidence strongly suggests an association between cigarette smoking and pancreatic injury, although effects of smoking on endocrine pancreas are still controversial.

OBJECTIVE

We examined the impact and underlying mechanisms of action of folic acid and vitamin B12 on nicotine-induced damage in pancreatic islets of rats.

MATERIALS AND METHODS

Male Wistar rats were treated with nicotine (3 mg/kg body weight/d, intraperitonealy) with or without folic acid (36 µg/kg body weight/d, orally) and vitamin B12 (0.63 µg/kg body weight/d, orally) for 21 d. Fasting blood glucose, oral glucose tolerance test, HBA1c, insulin, oxidative stress parameters, proinflammatory cytokines, and CRP level were measured. Histological evaluation, TUNEL assay, and immunohistochemical staining of NF-κB and caspase-3 were also performed.

RESULTS

Folic acid and vitamin B12 blunted the nicotine-induced impairment in fasting blood glucose (51-56% recovery), HbA1c (64-76% recovery), oral glucose tolerance, insulin level (23-40% recovery), and islet cell counts (26-74% recovery) in rats. Moreover, folic acid in combination with vitamin B12 also attenuated the nicotine-induced changes in markers of oxidative stress (17-88% recovery), TNF-α (40-99% recovery), and IL-6 level (47-65% recovery), CRP level (59-73% recovery), expression of NF-κB and caspase-3, and apoptosis in pancreatic islet cells.

DISCUSSION AND CONCLUSION

The present study shows that folic acid and vitamin B12 supplementation can reduce nicotine-induced impairment in glucose homeostasis and apoptosis and damage of pancreatic islet cells by modulating oxidative stress, levels of proinflammatory cytokines, and expression of NF-κB.

Enhancement of Curcumin Fluorescence by Ascorbic Acid in Bicontinuous Microemulsion

Steady-state fluorescence spectro-photometric technique is used in this work to determine the chemical parameters of the complex formed between curcumin and ascorbic acid in bicontinuous microemuslion (Bμen). The Bμen liquid used is made up of a four-components system (water-oil-surfactant and co-surfactant (1-pentanol)) in the ratio of 42.11:13.7:21.34:22.85 % w/w. The oil and surfactant used are tetradecane and cetyltrimethylammonium bromide. Curcumin is known to have low solubility in water, but liberally soluble in Bμen, hence the use of Bμen in this study. The observed fluorescence intensity of curcumin was enhanced by introduction of ascorbic acid to the curcumin solution. The increase in the fluorescence intensity showed a very good linearity with a regression coefficient of 0.9974. The association constant, Ka, that resulted between curcumin and ascorbic acid was calculated as 2.15 × 10(4) with the free energy of association, ∆Ga, of -24.71 kJ/mol. The ratio of the complex that was formed by these two molecules was determined as 1:1.

Aortic remodelling in chronic nicotine-administered rat

Vascular remodelling is an adaptive mechanism, which counteracts pressure changes in blood circulation. Nicotine content in cigarette increases the risk of hypertension. The exact relationship between nicotine and vascular remodelling still remain unknown. Current study was aimed to determine the effect of clinically relevant dosage of nicotine (equivalent to light smoker) on aortic reactivity, oxidative stress markers and histomorphological changes. Twelve age-matched male Sprague-Dawley rats were randomly divided into two groups, i.e.: normal saline as control or 0.6 mg/kg nicotine for 28 days (i.p., n=6 per group). On day-29, the rats were sacrificed and the thoracic aorta was dissected immediately for further studies. Mean arterial pressure (MAP) and pulse pressure (PP) of nicotine-treated vs. control were significantly increased (p<0.05). Nicotine-treated group showed significant (p<0.05) increase tunica media thickness, and decrease in lumen diameter, suggesting vascular remodelling which lead to prior hypertension state. The phenylephrine (PE)-induced contractile response in nicotine group was significantly higher than control group (ED50=1.44×10(5) M vs. 4.9×10(6) M) (p<0.05~0.001). However, nicotine-treated rat showed significantly lower endothelium-dependent relaxation response to acetylcholine (ACh) than in control group (ED50=6.17×10(7) M vs. 2.82×10(7) M) (p<0.05), indicating loss of primary vascular function. Malondialdehyde (MDA), a lipid peroxidation marker was significantly higher in nicotine group. Superoxide dismutase (SOD) enzymatic activity and glutathione (GSH) were all reduced in nicotine group (p<0.05) vs. control, suggesting nicotine induces oxidative imbalance. In short, chronic nicotine administration impaired aortic reactivity, probably via redox imbalance and vascular remodelling mechanism.

Trace elements and oxidative stress levels in the blood of painters in Lagos, Nigeria: occupational survey and health concern

Adverse effects attributed to exposure to paints are currently a concern because of the continued widespread use of paint containing trace elements. Thus, occupational survey amongst painters in Lagos and determination of trace elements and oxidative stress parameters were carried out. Descriptive cross-sectional survey was done using a standardized questionnaire to obtain job safety-related information. Forty-eight percent of the painters were aware of hazards associated with painting and 52 % of these workers were aware of the necessary precautionary measures during painting. There were no significant differences (p ≥ 0.05) between the levels of trace elements in the blood of painters and the control subjects. However, there was a significance increase (p ≤ 0.0001) in the level of malondialdehyde and a decrease (p ≤ 0.001) in the levels of reduced glutathione, superoxide dismutase, and catalase of the painters compared to the control. An increase in oxidative stress parameters may not only be due to trace element concentrations, but also the painters' exposure to some petrochemical solvents during mixing of paints.

Staphylococcus aureus Infection Induced Oxidative Imbalance in Neutrophils: Possible Protective Role of Nanoconjugated Vancomycin

Staphylococcus aureus infection causes oxidative stress in neutrophils. The immune cells use reactive oxygen species (ROS) for carrying out their normal functions while an excess amount of ROS can attack cellular components that lead to cell damage. The present study was aimed to test the protective role of nanoconjugated vancomycin against vancomycin-sensitive Staphylococcus aureus (VSSA) and vancomycin-resistant Staphylococcus aureus (VRSA) infection induced oxidative stress in neutrophils. VSSA- and VRSA-infection were developed in Swiss mice by intraperitoneal injection of 5 × 10(6) CFU/mL bacterial solutions. Nanoconjugated vancomycin was treated to VSSA- and VRSA-infected mice at its effective dose for 10 days. Vancomycin was treated to VSSA and VRSA infected mice at similar dose, respectively, for 10 days. The result reveals that in vivo VSSA and VRSA infection significantly increases the level of lipid peroxidation, protein oxidation, oxidized glutathione level, and nitrite generation and decreases the level of reduced glutathione, antioxidant enzyme status, and glutathione-dependent enzymes as compared to control group; which were increased or decreased significantly near to normal in nanoconjugated vancomycin-treated group. These finding suggests the potential use and beneficial protective role of nanoconjugated vancomycin against VSSA and VRSA infection induced oxidative imbalance in neutrophils.

Internalization of Staphylococcus aureus in lymphocytes induces oxidative stress and DNA fragmentation: possible ameliorative role of nanoconjugated vancomycin

Staphylococcus aureus is the most frequently isolated pathogen causing bloodstream infections, skin and soft tissue infections and pneumonia. Lymphocyte is an important immune cell. The aim of the present paper was to test the ameliorative role of nanoconjugated vancomycin against Vancomycin-sensitive Staphylococcus aureus (VSSA) and vancomycin-resistant Staphylococcus aureus (VRSA) infection-induced oxidative stress in lymphocytes. VSSA and VRSA infections were developed in Swiss mice by intraperitoneal injection of 5 × 10⁶ CFU/mL bacterial solutions. Nanoconjugated vancomycin was adminstrated to VSSA- and VRSA-infected mice at its effective dose for 10 days. Vancomycin was adminstrated to VSSA- and VRSA-infected mice at a similar dose, respectively, for 10 days. Vancomycin and nanoconjugated vancomycin were adminstrated to normal mice at their effective doses for 10 days. The result of this study reveals that in vivo VSSA and VRSA infection significantly increases the level of lipid peroxidation, protein oxidation, oxidized glutathione level, nitrite generation, nitrite release, and DNA damage and decreases the level of reduced glutathione, antioxidant enzyme status, and glutathione-dependent enzymes as compared to control group, which were increased or decreased significantly near to normal in nanoconjugated vancomycin-treated group. These findings suggest the potential use and beneficial role of nanoconjugated vancomycin against VSSA and VRSA infection-induced oxidative stress in lymphocytes.

Amelioratory Effect of Nanoconjugated Vancomycin on Spleen during VRSA-Induced Oxidative Stress

Objective. The aim of the present study was to evaluate the possible antioxidant effects of nanoconjugated vancomycin against VRSA infection on select makers of oxidative damage and antioxidant status in spleen. Methods. A coagulase-positive VRSA strain was used for this study. VRSA infection was developed in Swiss mice by intraperitoneal injection of 5 × 10(6) CFU/mL bacterial solutions. VRSA-infected mice were treated with nanoconjugated vancomycin at its effective dose for 10 days. After decapitation, blood was used for determination of viable bacteria count and spleen was excised from control and experimental groups, homogenized and used for different biochemical estimations. Results. Nitrate level, myeloperoxidase activity, lipid peroxidation, protein oxidation, oxidized glutathione, and DNA fragmentation level were increased significantly (P < 0.05) in spleen of VRSA-infected group as compared to control group, and reduced glutathione level, activity of SOD, CAT, GPx, GR, and GST were decreased significantly (P < 0.05); which were increased or decreased significantly (P < 0.05) near to normal in nanoconjugated vancomycin-treated group. Conclusion. These findings suggest the potential use and beneficial role of nanoconjugated vancomycin against VRSA-infection-induced oxidative stress and DNA damage in spleen.

Host-guest complexations of local anaesthetics by cucurbit[7]uril in aqueous solution

The cucurbit[7]uril (CB[7]) host molecule forms very stable host-guest complexes with the local anaesthetics procaine (K(CB[7]) = (3.5 +/- 0.7) x 10(4) dm(3) mol(-1)), tetracaine (K(CB[7]) = (1.5 +/- 0.4) x 10(4) dm(3) mol(-1)), procainamide (K(CB[7]) = (7.8 +/- 1.6) x 10(4) dm(3) mol(-1)), dibucaine (K(CB[7]) = (1.8 +/- 0.4) x 10(5) dm(3) mol(-1)) and prilocaine (K(CB[7]) = (2.6 +/- 0.6) x 10(4) dm(3) mol(-1)) in aqueous solution (pD = 4.75). The stability constants are 2-3 orders of magnitude greater than the values reported for binding by the comparably sized beta-cyclodextrin host molecule. The inclusion by CB[7] raises the first pK(a) values of the anaesthetics by 0.5-1.9 pK units, as the protonated forms are bound more strongly in acidic solution. The complexation-induced chemical shift changes in the guest proton resonances provide an indication of the site(s) of binding and the effects of protonation on the location of the binding sites.

Selenium and vitamin E modulates cigarette smoke exposure-induced oxidative stress in blood of rats

Cigarette smoke contains about 5,000 chemicals that include organic and metallic compounds. The current study was undertaken to investigate the effects of selenium and vitamin E on oxidative stress-induced damage in rats exposed to cigarette smoke. Forty male rats were equally divided into four groups. The first and second groups were used as control and cigarette smoke groups, respectively. Selenium was administered to rats constituting the third group for 27 days. The Se and vitamin E combination was given to animals in fourth group for 27 days. All groups except the control, were exposed to cigarette smoke starting at the third day of the experiment and continuing for 27 days. The blood samples from all groups were taken at the end of 27 days. Plasma lipid peroxidation, triacylglycerol, and total cholesterol levels were higher in the cigarette smoke group than in the control, although erythrocytic superoxide dismutase and glutathione peroxidase activities were lower in the cigarette smoke group than in the control. The plasma lipid peroxidation, triacylglycerol, and total cholesterol levels were lower in cigarette smoke+Se+VE group than in the cigarette smoke group, although erythrocytic superoxide dismutase activity and glutathione peroxidase activity in selenium and vitamin E-administered groups were higher than in the exposed to cigarette smoke group. High-density lipoprotein-cholesterol level was not affect by selenium and vitamin E administrations. In conclusion, selenium and vitamin E seem to have protective effects on the cigarette smoke-induced blood toxicity by supporting the enzymatic antioxidant redox systems.

Antihyperlipidemic effect of bis-1,7-(2-hydroxyphenyl)-hepta-1,6-diene-3,5-dione, a curcumin analog, on nicotine and streptozotocin treated rats

Diabetes and smoking have been considered as major health problems individually and their seriousness related to health hazard has been well reported. Data regarding the possible contribution of cigarette smoking to the development of diabetes are scarce and inconclusive. The aim was to investigate the effect of nicotine on diabetes and to analyze the effect of bis demethoxy curcumin analog (BDMCA) in streptozotocin (STZ) and nicotine-induced toxicity. The tissue lipids were extracted according to the method of Folch et al. Plasma and tissue cholesterol was estimated by the method of Allain et al. using reagent kit. Triglycerides were estimated by the method of Foster and Dunn. Free fatty acids were estimated by the method of Falholt et al. Tissue phospholipids were estimated by the method of Zilversmit and Davis. From our study, we found that nicotine not only aggravates diabetic complications but also increased the risk for diabetes. BDMCA, at a dose 80 mg/kg body weight was found to be effective in decreasing toxic effects induced by nicotine and STZ. Our data provide new evidence that cigarette smoking is an additional important factor that could be targeted for the prevention of diabetic complications.

Oxidative stress in the brain of nicotine-induced toxicity: protective role of Andrographis paniculata Nees and vitamin E

Mitochondria are the crossroads of several crucial cellular activities; they produce considerable quantities of superoxide radical and hydrogen peroxide, which can damage important macromolecules. Nicotine affects a variety of cellular processes, from induction of gene expression to modulation of enzymatic activities. The aim of this study was to elucidate the protective effects of andrographolide (ANDRO) aqueous extract (AE-Ap) of Andrographis paniculata, and vitamin E on nicotine-induced brain mitochondria. In this investigation, nicotine (1 mg.kg body mass-1.day-1) was treated, for the period of 7 days, simultaneously with 2 A. paniculata products, ANDRO and AE-Ap (250 mg.kg body mass-1.day-1); and vitamin E (50 mg.kg body mass-1.day-1) was supplemented in different group of male Wistar rats. The activities of mitochondrial electron transport chain (Mito-ETC) complexes (I, II, III), nitric oxide production, superoxide anion, catalase, glutathione reductase, glutathione peroxidase, glutathione-S-transferase, and concentrations of reduced glutathione and oxidized glutathione were measured in discrete regions of brain (the cerebral hemisphere, cerebellum, diencephalons, and brain stem). The study revealed that nicotine inhibits the Mito-ETC complexes and produces nitric oxide, which suppressed the mitochondrial oxidative stress scavenger system in different brain regions. In these circumstances, lipid peroxidation and protein oxidation were noted in different discrete regions of brain mitochondria. ANDRO, AE-Ap, and vitamin E showed the protective potentiality against nicotine toxicity. The analysis of such alterations is important in determining the basis of normal dysfunction in the brain associated with nicotine toxicity, which could be ameliorated by A. paniculata and vitamin E, and may help to develop therapeutic means against nicotine-induced disorders.

Prevention of nicotine and streptozotocin treatment induced circulatory oxidative stress by bis-1,7-(2-hydroxyphenyl)-hepta-1,6-diene-3,5-dione in diabetic rats

Diabetes and smoking have been considered as major health problems individually and their seriousness related to health hazard has been well reported. The role of nicotine in causing or worsening effect on diabetes is not well understood. The aim of our study was to investigate the effect of nicotine on experimental diabetes and to analyze the effect of bis-1,7-(2-hydroxyphenyl)-hepta-1,6-diene-3,5-dione a bisdemethoxy curcumin analog (BDMCA) in streptozotocin and nicotine induced toxicity. Group I: control rats; Group II: nicotine (2.5 mg/kg b.wt); Group III: streptozotocin (STZ) (40 mg/kg b.wt); Group IV: STZ (40 mg/kg b.wt) + nicotine (2.5 mg/kg b.wt); Group V: STZ + nicotine + BDMCA (40 mg/kg b.wt); Group VI: STZ + nicotine + BDMCA (80 mg/kg b.wt). Efficacy of BDMCA was determined by evaluating blood glucose, thiobarbituric acid reactive substances (TBARS), hydroperoxides (HP), activities of marker enzymes alkaline phosphatase (ALP), and lactate dehydrogenase (LDH) and activities of antioxidant enzymes superoxide dismutase (SOD), catalase (CAT) and glutathione peroxidase (GPx). From our study, we have observed that nicotine not only aggravates diabetic complications but also increased the risk for diabetes. BDMCA, at a dose 80 mg/kg body weight was found to be more effective in decreasing toxic effects induced by nicotine and STZ.

Curcumin or saikosaponin a improves hepatic antioxidant capacity and protects against CCl4-induced liver injury in rats

Curcumin and saikosaponin a, the bioactive phytochemicals of turmeric and Bupleurum, act as antioxidants. This study investigated the effects of supplementation with curcumin and/or saikosaponin a on hepatic lipids and antioxidant status in rats with CCl(4)-induced liver injury. Male Sprague-Dawley rats were randomly divided into control, CCl(4), CCl(4) + curcumin (0.005%; CU), CCl(4) + saikosaponin a (0.004%; SS), and CCl(4) + curcumin + saikosaponin a (0.005% + 0.004%; CU+SS) groups. CCl(4) (40% in olive oil) was injected intraperitoneally at a dose of 0.75 mL/kg once a week. Curcumin and/or saikosaponin a was administered orally 1 week before CCl(4) injection for 8 weeks. The pathological results showed that liver fibrosis was ameliorated in the SS and CU+SS groups. After 8 weeks, supplementation with curcumin and/or saikosaponin a significantly decreased plasma alanine aminotransferase and aspartate aminotransferase activities, as well as plasma and hepatic cholesterol and triglyceride levels. The CU+SS group showed reversal of the impaired hepatic superoxide dismutase activity and an increase in total glutathione level. Supplementation with curcumin and/or saikosaponin a significantly improved hepatic antioxidant status and suppressed malondialdehyde formation. Therefore, supplementation with curcumin and/or saikosaponin a protects against CCl(4)-induced liver injury by attenuating hepatic lipids and lipid peroxidation and enhancing antioxidant defense. Curcumin and saikosaponin a had no additive effects on hepatoprotection except for greater improvement in the total glutathione level and antioxidant status.

Antioxidant and anti-inflammatory properties of curcumin

Curcumin, a yellow pigment from Curcuma longa, is a major component of turmeric and is commonly used as a spice and food-coloring agent. It is also used as a cosmetic and in some medical preparations. The desirable preventive or putative therapeutic properties of curcumin have also been considered to be associated with its antioxidant and anti-inflammatory properties. Because free-radical-mediated peroxidation of membrane lipids and oxidative damage of DNA and proteins are believed to be associated with a variety of chronic pathological complications such as cancer, atherosclerosis, and neurodegenerative diseases, curcumin is thought to play a vital role against these pathological conditions. The anti-inflammatory effect of curcumin is most likely mediated through its ability to inhibit cyclooxygenase-2 (COX-2), lipoxygenase (LOX), and inducible nitric oxide synthase (iNOS). COX-2, LOX, and iNOS are important enzymes that mediate inflammatory processes. Improper upregulation of COX-2 and/or iNOS has been associated with the pathophysiology of certain types of human cancer as well as inflammatory disorders. Because inflammation is closely linked to tumor promotion, curcumin with its potent anti-inflammatory property is anticipated to exert chemopreventive effects on carcinogenesis. Hence, the past few decades have witnessed intense research devoted to the antioxidant and anti-inflammatory properties of curcumin. In this review, we describe both antioxidant and anti-inflammatory properties of curcumin, the mode of action of curcumin, and its therapeutic usage against different pathological conditions.

CURCUMIN: THE INDIAN SOLID GOLD

Turmeric, derived from the plant Curcuma longa, is a gold-colored spice commonly used in the Indian subcontinent, not only for health care but also for the preservation of food and as a yellow dye for textiles. Curcumin, which gives the yellow color to turmeric, was first isolated almost two centuries ago, and its structure as diferuloylmethane was determined in 1910. Since the time of Ayurveda (1900 Bc) numerous therapeutic activities have been assigned to turmeric for a wide variety of diseases and conditions, including those of the skin, pulmonary, and gastrointestinal systems, aches, pains, wounds, sprains, and liver disorders. Extensive research within the last half century has proven that most of these activities, once associated with turmeric, are due to curcumin. Curcumin has been shown to exhibit antioxidant, anti-inflammatory, antiviral, antibacterial, antifungal, and anticancer activities and thus has a potential against various malignant diseases, diabetes, allergies, arthritis, Alzheimer's disease, and other chronic illnesses. These effects are mediated through the regulation of various transcription factors, growth factors, inflammatory cytokines, protein kinases, and other enzymes. Curcumin exhibits activities similar to recently discovered tumor necrosis factor blockers (e.g., HUMIRA, REMICADE, and ENBREL), a vascular endothelial cell growth factor blocker (e.g., AVASTIN), human epidermal growth factor receptor blockers (e.g., ERBITUX, ERLOTINIB, and GEFTINIB), and a HER2 blocker (e.g., HERCEPTIN). Considering the recent scientific bandwagon that multitargeted therapy is better than monotargeted therapy for most diseases, curcumin can be considered an ideal "Spice for Life".

Protection from acute and chronic lung diseases by curcumin

The aim of this review has been to describe the current state of the therapeutic potential of curcumin in acute and chronic lung injuries. Occupational and environmental exposures to mineral dusts, airborne pollutants, cigarette smoke, chemotherapy, and radiotherapy injure the lungs, resulting in acute and chronic inflammatory lung diseases. Despite major advances in treating lung diseases, until now disease-modifying efficacy has not been demonstrated for any of the existing drugs. Current medical therapy offers only marginal benefit; therefore, there is an essential need to develop new drugs that might be of effective benefit in clinical settings. Over the years, there has been increasing evidence that curcumin, a phytochemical present in turmeric (Curcuma longa), has a wide spectrum of therapeutic properties and a remarkable range of protective effects in various diseases. Several experimental animal models have tested curcumin on lung fibrosis and these studies demonstrate that curcumin attenuates lung injury and fibrosis caused by radiation, chemotherapeutic drugs, and toxicants. The growing amount of data from pharmacological and animal studies also supports the notion that curcumin plays a protective role in chronic obstructive pulmonary disease, acute lung injury, acute respiratory distress syndrome, and allergic asthma, its therapeutic action being on the prevention or modulation of inflammation and oxidative stress. These findings give substance to the possibility of testing curcumin in patients with lung diseases.

Hypolipidemic and antioxidant effects of curcumin and capsaicin in high-fat-fed rats

The beneficial hypolipidemic and antioxidant influences of the dietary spice compounds curcumin and capsaicin were evaluated. Curcumin, capsaicin, or their combination were included in the diet of high-(30%)-fat-fed rats for 8 weeks. Dietary high-fat-induced hypertriglyceridemia was countered by dietary curcumin, capsaicin, or their combination by 12%–20%. Curcumin, capsaicin, and their combination also produced a slight decrease in serum total cholesterol in these animals. Serum α-tocopherol content was increased by dietary curcumin, capsaicin, and their combination in high-fat-fed rats. Serum total thiol content in high-fat-fed animals and serum ascorbic acid in normal animals was elevated by the combination of curcumin and capsaicin. Hepatic glutathione was increased by curcumin, capsaicin, or their combination in normal animals. Hepatic glutathione and α-tocopherol were increased, whereas lipid peroxide level was reduced by dietary curcumin and combination of curcumin and capsaicin in high-fat-fed animals. Serum glutathione peroxidase and glutathione transferase in high-fat-fed rats were generally higher as a result of dietary curcumin, capsaicin, and the combination of curcumin and capsaicin. Hepatic glutathione reductase and glutathione peroxidase were significantly elevated by dietary spice principles in high-fat-fed animals. The additive effect of the 2 bioactive compounds was generally not evident with respect to hypolipidemic or antioxidant potential. However, the effectiveness of the combination was higher in a few instances.

Molecular Electrostatic Potentials and Hydrogen Bonding in α-, β-, and γ-Cyclodextrins

Cyclodextrins (CDs) are cyclic oligomers of glucose having the toroid of sugars elaborating a central cavity of varying size depending on the number of glucoses. The central hydrophobic cavity of CD shows a binding affinity toward different guest molecules, which include small substituted benzenes to long chain surfactant molecules leading to a variety of inclusion complexes when the size and shape complementarity of host and guest are compatible. Further, interaction of guest molecules with the outer surface of alpha-CD has also been observed. Primarily it is the electrostatic interactions that essentially constitute a driving force for the formation of inclusion complexes. To gain insights for these interactions, the electronic structure and the molecular electrostatic potentials in alpha-, beta-, and gamma-CDs are derived using the hybrid density functional theory employing the three-parameter exchange correlation functional due to Becke, Lee, Yang, and Parr (B3LYP). The present work demonstrates how the topography of the molecular electrostatic potential (MESP) provides a measure of the cavity dimensions and understanding of the hydrogen-bonded interactions involving primary and secondary hydroxyl groups. In alpha-CD, hydrogen-bonded interactions between primary -OH groups engender a "cone-like" structure, while in beta- or gamma-CD the interactions from the primary -OH with ether oxygen in glucose ring facilitates a "barrel-like" structure. Further, the strength of hydrogen-bonded interactions of primary -OH groups follows the rank order alpha-CD > beta-CD > gamma-CD, while the secondary hydrogen-bonded interactions exhibit a reverse trend. Thus weak hydrogen-bonded interactions prevalent in gamma-CD manifest in shallow MESP minima near hydroxyl oxygens compared to those in alpha- or beta-CD. Furthermore, electrostatic potential topography reveals that the guest molecule tends to penetrate inside the cavity forming the inclusion complex in beta- or gamma-CD.

Theoretical Study of the α-Cyclodextrin Dimer

The molecular structure, stabilization energy, and thermodynamic properties of the plausible modes of the interaction for the three possible alpha-cyclodextrin (alpha-CD) dimers (head-to-head, tail-to-tail, and head-to-tail) with a water cluster were obtained using quantum chemical methods for the first time. Nine distinct spatial arrangements were investigated. The head-to-head mode of interaction with water is preferred by more than 10 kcal.mol(-1) (BLYP/6-31G(d,p)//PM3 Gibbs free energy difference value at room temperature) in relation to the next stable structure, with a water dimer structure placed inside each cavity and cyclic water tetramers surrounding each tail end. The inter alpha-CD hydrogen bonds play a major role to stabilize the dimeric structures, with no water tetramer being found between the two alpha-CD subunits for the preferred global minimum structure. Therefore, a theoretical model aimed to describe the behavior of alpha-CD dimer, or their inclusion complexes, in the aqueous media should take into account this preference for binding of the water molecules.