Anti-inflammatory Activity Of Curcumin Research Articles

Curcumin Lowers the Accelerated Speed of Epileptogenesis by Traumatic Brain Injury.

Traumatic brain injury or TBI can underlie epilepsy. Prevention of PTE has been of great interest to scientists. Given the antiepileptic, antioxidant and anti-inflammatory activities of curcumin, we examined whether this compound can affect epileptogenesis in rats after TBI. Curcumin was injected once a day for two weeks. TBI was induced in the temporal cortex of anesthetized rats using a CCI device. One day after TBI, PTZ, 35 mg/kg, was injected i.p. every other day until manifestation of generalized seizures. The number of PTZ injections was then recorded. Moreover, the extent of cortical and hippocampal IL-1β and GFAP expression in the epileptic rats were measured by Western blot analysis. Curcumin 50 and 150 mg/kg prevented the development of kindling, wherase TBI accelerated the rate of kindling. Curcumin 20 mg/kg prohibited kindling facilitation by TBI, and reduced the expression of IL-1β and GFAP induced by TBI. Curcumin can stop the acceleration of epileptogenesis after TBI in rats. Inhibiting hippocampal and cortical overexpression of IL-1β and GFAP seems to be involved in this activity.

Curcumin Niosomes Prepared from Proniosomal Gels: In Vitro Skin Permeability, Kinetic and In Vivo Studies.

Curcumin is a poorly water-soluble drug that is used for the treatment of inflammations, tumors, wound healing antioxidant and other diseases. In the current manuscript, it is successfully formulated into proniosome gels. The proniosomes are readily hydrated into niosomal formulations using warm water. Proniosomes were prepared using nonionic surfactants (tween 80, span 60) either solely or in combinations with cholesterol. The produced niosomal formulations were homogenous in size with vesicular sizes >343 and <1800 nm. The encapsulation efficiency percentage “EE%” of curcumin in niosomal formulations was different according to niosomal composition. It increased up to 99.74% in formulations of tween 80/Chol of 200 μmole/mL lipid concentration. Span 60/chol niosomes showed decreased curcumin EE%. Niosomal formulations showed increased SSTF and PC with enhancement ratios of more than 20-fold compared with curcumin suspension form. Kinetically, niosomes fitted to the Korsemeyer-Peppas model with non-Fickian transport according to their calculated n-values where curcumin suspension form showed Korsemeyer-Peppas kinetics with Fickian transport. Niosomal formulations deposited higher curcumin amounts in the skin compared with the suspension form. The best niosomal formulation (F9) was used for niosomal gel and emulgel fabrication. Finally, the anti-inflammatory activity of curcumin in various formulations was evaluated using a rat hind paw edema method and the % of swelling was 17.5% following 24 h in group treated with curcumin niosomal emulgel. In conclusion, this study suggests that the developed niosomal emulgel could significantly enhance the anti-inflammatory effect of curcumin and be an efficient carrier for the transdermal delivery of the drug.

Curcumin: Natural Antimicrobial and Anti Inflammatory Agent

The pursuance of novel antimicrobial and anti-inflammatory agents has been expanding due to a significant need for more efficient pharmacotherapy of various infections and chronic diseases. During the last decade, pharmacokinetics, pharmacodynamics and pharmacological properties of curcumin have been extensively studied. The aim of the present study was to evaluate the antibacterial activity of curcumin against both Gram-positive and Gram-negative bacteria as well as its antifungal activity by using in vitro agar well diffusion assay. Moreover, the anti-inflammatory activity of curcumin was determined with in vitro assay of inhibition of protein denaturation. Results demonstrated wide antimicrobial activity of curcumin upon all of the test bacteria and fungi. The strongest activity of curcumin was observed at a concentration of 0.50 mg/ml against S. aureus, L. monocytogenes, E. coli, P. aeruginosa and C. albicans, resulting in a maximum zone of inhibition of 14.7 mm, 14.3 mm, 13.7 mm, 10.7 mm and 10.7 mm, respectively. Findings suggested that the antimicrobial activity of curcuminis dependent upon the concentrations. Furthermore, results demonstrated high effectiveness of curcumin compared to standard acetylsalicylic acid in inhibiting heat-induced protein denaturation, which activity is also depended upon the concentrations. The present study emphasises the potential application of curcumin as a natural antimicrobial and anti-inflammatory agent. However, findings of this study are restricted to in vitro assays and consideration should be given to conducting a study involving wider dose range test substances as well as including further research on in vivo models.

The Preventive Effect of Curcumin on the Experimental Rat Epidural Fibrosis Model

The aim of the study was to evaluate the effect of systemically administrated curcumin on the prevention of peridural fibrotic tissue and adhesion formation in a rat laminectomy model. Thirty-two Wistar albino rats were randomly selected and equally divided into 4 groups as follows: negative control group (group I) did not undergo operation; positive control group (group II) underwent laminectomy without treatment; group III (low-dose curcumin; 100 mg/kg); and group IV (high-dose curcumin; 200 mg/kg). Curcumin was administered intraperitoneally per day for 7 days after surgery starting from day 0. Twenty-eight days after surgery, T12 and L4 vertebral columns, paraspinal tissues, and epidural scar tissue were dissected en bloc and prepared for histopathologic examinations. All specimens were examined for inflammation, epidural fibrosis (EF), foreign body reaction, medulla spinalis retraction, granulation tissue, and arachnoid involvement. A Kruskal-Wallis test followed by a Dunn multiple comparison test were used for statistical analysis, and a P value <0.05 was considered as statistically significant. Curcumin treatment significantly reduced inflammation, foreign body reaction, granulation tissue formation, medulla spinalis retraction, and EF formation compared with positive control group (P < 0.05); however, no significant differences were found between the 2 groups that received different doses of curcumin. The results of the present study showed that systemic administration of curcumin was effective in reducing EF formation, inflammation, granulation tissue formation, medulla spinalis retraction, and foreign body reaction in the laminectomy area. Our results suggest that antiinflammatory activities of curcumin are beneficial for attenuation of EF formation.

Protective effect of curcumin on fertility in cyclophosphamide exposed rats: Involvement of multiple pathways.

This study assesses the effect of curcumin on cyclophosphamide (CPA)-induced functional alterations of the testicular, brain, and pituitary axis in common rodents, rats. Only CPA was given at 150mg/kg body weight only on Day 1 or orally pre and posttreated with curcumin at 20mg/kg body weight successively for 14days. The outcomes showed that curcumin pre and posttreatments significantly affected the elevation of biomarkers of oxidative stress in CPA-induced rats, moreover, it increased nonenzymatic antioxidant levels in the epididymis, testes, and brain of the treated rats used in this study. In addition, followed by the preservation of histo-architectures of the epididymis, testes, and brain in the rats treated with CPA, curcumin helped in increasing the sperm quality and quantity and suppressing both the inflammatory indices and the activities of caspase-3, while pretreatment with curcumin gave a better result than posttreatment with curcumin. This may, therefore, represent a prospective adjuvant against CPA-induced spermatogenic deficits in humans. PRACTICAL APPLICATIONS: Jointly, through the antiapoptotic, antioxidant, and anti-inflammatory activities of curcumin, it instigated the toxicity of CPA-induced to be modulated along the testicular, brain, and pituitary axis in the rats. This may, therefore, represent a prospective therapeutic adjuvant against CPA-induced spermatogenic deficits in humans.

Curcumin improves step 4 asthma treatment: placebo-controlled, single blind study

Background: Despite multistep efforts, many asthma patients remain symptomatic. Anti-inflammatory activities of curcumin are shown. Aim of the study was to analyse the impact of curcumin add-on therapy on inflammatory parameters, lung function, disease control and quality of life in asthma patients. Subjects and methods: Three-months lasting study was done on 150 non-smokers with asthma, that were treated with stable, moderate dose of inhaled glucocorticoids (IGK) and divided into three groups (n=50 each): curcumin group (receiving curcumin 500 mg per os twice daily), placebo group (receiving placebo tablets) and control (non-intervention) group. Sputum eosinophils (sEo), blood eosinophils (bEo), high sensitive C-reactive protein (hsCRP), predicted forced expiratory volume in first second (FEV1%), Asthma Control Test (ACT) and mini Asthma Quality of Life Questionnaire (mAQLQ) were compared before and after study, as well as between groups. Results: Before study, all followed parameters were similar between groups. After study, FEV1%, ACT and AQLQ were improved in all groups, but these improvements were more prominent in curcumin group than in placebo and control. Additionally curcumin group only showed improvement in sEo, bEo and hsCRP. Furthermore, curcumin group showed more frequent clinically significant improvement in ACT score (change>3) and in mAQLQ score (change≥0.5) when compared to placebo and control. On the other side, after study FEV1%, ACT, mAQLQ, hsCRP, sEo and bEo were similarly distributed among placebo and control group. Conclusion: This is the first placebo controlled and single-blind study to suggest that add-on therapy with curcumin could improve lung function, disease control and quality of life in moderate partially controlled asthma. Future studies may benefit from a larger sample size, longer study duration, double blind design, different dose of curcumin and/or improvements in oral bioavailability

Assessing the potential of liposomes loaded with curcumin as a therapeutic intervention in asthma.

Curcumin a component of turmeric, which is derived from Curcuma longa is used as a colouring agent and as a dietary spice for centuries. Extensive studies have been done on the anti-inflammatory activity of curcumin along with its molecular mechanism involving different signalling pathways. However, the physicochemical and biological properties such as poor solubility and rapid metabolism of curcumin have led to low bioavailability and hence limits its application. Current therapies for asthma such as bronchodilators and inhaled corticosteroids (ICS) are aimed at controlling disease symptoms and prevent asthma exacerbation. However, this approach requires lifetime therapy and is associated with a constellation of side effects. This creates a clear unmet medical need and there is an urgent demand for new and more-effective treatments. The present study is aimed to formulate liposomes containing curcumin and evaluate for its anti-inflammatory effects on lipopolysaccharide (LPS)-induced inflammation on BCi-NS1.1 cell line. Curcumin and salbutamol liposomes were formulated using lipid hydration method. The prepared liposomes were characterized in terms of particle size, zeta potential, encapsulation efficiency and in-vitro release profile. The liposomes were tested on BCI-NS1.1 cell line to evaluate its anti-inflammatory properties. The various pro-inflammatory markers studied were Interleukin-6 (IL-6), Interleukin-8 (IL-8), Interleukin-1β (IL-1β) and Tumour Necrosis Factor-a (TNF-a). Additionally, molecular mechanics simulations were used to elucidate the positioning, energy minimization, and aqueous dispersion of the liposomal architecture involving lecithin and curcumin. The prepared curcumin formulation showed an average size and zeta potential of 271.3 ± 3.06 nm and -61.0 mV, respectively. The drug encapsulation efficiency of liposomal curcumin is 81.1%. Both curcumin-loaded liposomes formulation (1 μg/mL, 5 μg/mL) resulted in significant (p < 0.05) reduction in the level of pro-inflammatory marker expression such as IL-6, IL-8, IL-1β and TNF-a compared to positive control group. Liposomal curcumin with the dose of 1 μg/mL reduced the inflammatory markers more effectively compared to that of 5 μg/mL. Liposomal curcumin could be a promising intervention for asthma therapy showing their efficacy in suppressing the important pro-inflammatory markers involved in the pathogenesis of asthma.

Antioxidant Potential, Anti-Inflammatory and Hepatoprotective Effect of Curcumin in a Rat Model of Hepatotoxicity

Curcumin [1,7- bis (4-hydroxy-3-methoxyphenyl)- 1,6- heptadiene- 3,5-dione] was shown to exert potent antioxidant, anti-inflammatory and hepatoprotective properties. This study was done to investigate the protective effects of curcumin in thioacetamide (TAA)-induced hepatic injury in rats. Thirty-six male albino rats were divided into three equal groups. Group I (normal control group). Group II (TAA-intoxicated group): rats received thioacetamide (50 mg/kg b. wt. ip) twice weekly for 6 weeks. Group III (TAA + curcumin co-treated group): rats received thioacetamide (50 mg/kg b. wt.) and simultaneously administered curcumin (200 mg/kg b. wt./daily/orally) for 6 weeks (end of experiment). All animals were sacrificed after 6 weeks. TAA administration induced liver damage manifested by the significant increases in serum levels of ALT, AST, ALP and total bilirubin compared with control group. Oxidative stress in the group II was manifested by a significant rise in L-MDA levels with a marked reduction in the activities of antioxidant enzymes like GST, catalase CAT and depletion of GSH content in liver tissues as compared with the control group. On the other hand, TAA significantly affected the inflammation markers represented by elevation of myeloperoxidase (MPO) activities and upregulation of interleukin-6 (IL-6) gene expression levels in liver tissues. The coadministration of curcumin and thioacetamide (protection modality) prevented liver injury by normalizing the biochemical parameters, lipid peroxidation index and improving the protein oxidation, inflammatory markers and the antioxidant status. These findings suggested that, liver injury could be curtailed by the antioxidant and anti-inflammatory activities of curcumin and the normal status of the liver could be preserved.

Retinal Protection and Distribution of Curcumin in Vitro and in Vivo.

Diabetic retinopathy (DR), a secondary complication of diabetes, is a leading cause of irreversible blindness accounting for 5% of world blindness cases in working age. Oxidative stress and inflammation are considered causes of DR. Curcumin, a product with anti-oxidant and anti-inflammatory properties, is currently proposed as oral supplementation therapy for retinal degenerative diseases, including DR. In this study we predicted the pharmacodynamic profile of curcumin through an in silico approach. Furthermore, we tested the anti-oxidant and anti-inflammatory activity of curcumin on human retinal pigmented epithelial cells exposed to oxidative stress, human retinal endothelial and human retinal pericytes (HRPCs) cultured with high glucose. Because currently marketed curcumin nutraceutical products have not been so far evaluated for their ocular bioavailability; we assessed retinal distribution of curcumin, following oral administration, in rabbit eye. Curcumin (10 μM) decreased significantly (p < 0.01) ROS concentration and TNF-α release in retinal pigmented epithelial cells and retinal endothelial cells, respectively. The same curcumin concentration significantly (p < 0.01) protected retinal pericytes from high glucose damage as assessed by cell viability and LDH release. Among the tested formulations, only that containing a hydrophilic carrier provided therapeutic levels of curcumin in rabbit retina. In conclusion, our data suggest that curcumin, when properly formulated, may be of value in clinical practice to manage retinal diseases.

Effectiveness of Curcumin Therapy against Inflammation and Cancers

Plant isolated compounds have been in use to treat various ailments and to support normal physiological functions since long. Curcumin is also known for its beneficial health effects in the world of phytochemicals. Chemical name of curcumin is diferuloylmethane and it is extracted from turmeric and used for the prevention and cure of different inflammatory diseases. Inflammation is one of the root causes of diseases like arthritis, obesity, metabolic diseases like type II diabetes, pancreatitis, and neurodegenerative diseases cardiovascular even certain types of cancer. In Ayurveda medicine, turmeric has long been used for the treatment of different inflammatory disorders. Recent studies have shown that turmeric has an ingredient curcumin that is effectively applicable to therapeutic processes. Further, evidence has shown that inflammatory cell invasion, proliferation and angiogenesis can be inhibited using curcumin, through multiple molecular targets. Anti-inflammatory activity of Curcumin is carried out by suppressing of protein kinases, inflammatory cytokines, transcription factors, and enzymes that all promote inflammation, thus acts as a safe and non-toxic drug. However, curcumin’s efficacy is hindered by poor absorption and low bioavailability, which limit its translation into clinics. This study summarizes anti-inflammatory and anticancer effects of curcumin.

The anti-inflammatory activity of curcumin is mediated by its oxidative metabolites

The spice turmeric, with its active polyphenol curcumin, has been used as anti-inflammatory remedy in traditional Asian medicine for centuries. Many cellular targets of curcumin have been identified, but how such a wide range of targets can be affected by a single compound is unclear. Here, we identified curcumin as a pro-drug that requires oxidative activation into reactive metabolites to exert anti-inflammatory activities. Synthetic curcumin analogs that undergo oxidative transformation potently inhibited the pro-inflammatory transcription factor nuclear factor κB (NF-κB), whereas stable, non-oxidizable analogs were less active, with a correlation coefficient (R2) of IC50versus log of autoxidation rate of 0.75. Inhibition of glutathione biosynthesis, which protects cells from reactive metabolites, increased the potency of curcumin and decreased the amount of curcumin-glutathione adducts in cells. Oxidative metabolites of curcumin adducted to and inhibited the inhibitor of NF-κB kinase subunit β (IKKβ), an activating kinase upstream of NF-κB. An unstable, alkynyl-tagged curcumin analog yielded abundant adducts with cellular protein that were decreased by pretreatment with curcumin or an unstable analog but not by a stable analog. Bioactivation of curcumin occurred readily in vitro, which may explain the wide range of cellular targets, but if bioactivation is insufficient in vivo, it may also help explain the inconclusive results in human studies with curcumin so far. We conclude that the paradigm of metabolic bioactivation uncovered here should be considered for the evaluation and design of clinical trials of curcumin and other polyphenols of medicinal interest.

A mechanistic insight into curcumin modulation of the IL-1β secretion and NLRP3 S-glutathionylation induced by needle-like cationic cellulose nanocrystals in myeloid cells

Recently we have demonstrated that needle-like cationic cellulose nanocrystals (CNC-AEMA2) evoke immunological responses through NLRP3 inflammasome/IL-1β inflammatory pathway. In this study we demonstrated that curcumin, a naturally occurring polyphenolic compound isolated from Curcuma longa (Zingiberaceae), was able to suppress, at least in part, this immunological response, as observed by diminished IL-1β secretion in CNC-AEMA2-stimulated macrophages primed with LPS. Curcumin is a well-known antioxidant and anti-inflammatory natural compound and in addition to acting as “scavenger” of reactive oxygen species (ROS), it can also upregulates antioxidant enzymes. However, the mechanisms by which this natural compound exerts its protective activity is still under investigation. We hypothesize that curcumin may also affect S-glutathionylation of key proteins involved in the NLRP3 inflammasome/IL-1β pathway, and therefore impact their protein-protein interactions. The goal of this study was to investigate the effects of curcumin on the S-glutathionylation of NLRP3 induced by CNC-AEMA2 in LPS-primed mouse macrophages (J774A.1), as well as interactions among proteins of the NLRP3 inflammasome complex. Our main finding indicates that the addition of curcumin concomitantly with LPS caused the greatest decrease in NLRP3 S-glutathionylation and a respective increase in caspase-1 S-glutathionylation, which appears to favor protein-protein interactions in the NLRP3 complex. Taking together, our results suggest that, at least in part, the anti-inflammatory activity of curcumin is associated with changes in S-glutathionylation of key NLRP3 inflammasome components, and perhaps resulting in sustained complex assembly and suppression of IL-1β secretion.

Anti-inflammatory effects of curcumin are associated with down regulating microRNA-155 in LPS-treated macrophages and mice

Context: The natural polyphenolic compound curcumin has been proved to modulate innate immune responses and possess anti-inflammatory properties. Nevertheless, the mechanism remains poorly understood, particularly regarding curcumin-regulated miRNAs under inflammatory response.Objective: This study investigates the role of miRNA-155 in the effects of curcumin on inflammatory response in cell and a mouse model.Materials and methods: The anti-inflammatory activity of curcumin (5, 10 and 15 μM, 2 h) in lipopolysaccharide (LPS, 200 ng/mL)-induced cells were measured by quantitative PCR. The animals were treated orally by 20 mg/kg curcumin for 3 days before an LPS intraperitoneal injection (10 mg/kg, 16 h). MicroRNA (miRNA) expression and the underlying molecular mechanisms were assessed using transfection technique and western blotting.Results and discussion: Curcumin efficiently inhibited LPS-induced cytokines (TNF-α, IL-6) and microRNA-155 (miR-155) expression (p < 0.05) without affecting the normally growth of Raw264.7 and THP-1 cells (IC50 21.8 and 22.3 μM at 48 h, respectively). Moreover, the levels of cytokines were suppressed by curcumin in miR-155 mimics transfected cells (p < 0.05). A blockade of PI3K/AKT signalling pathways resulted in a decreased level of miR-155 (p < 0.05). Curcumin effectively protected mice from sepsis as evidenced by decreasing histological damage, reducing AST (352.0 vs 279.3 U/L), BUN (14.8 vs 10.8 mmol/L) levels and the proportion of macrophages in spleen (31.1% vs 13.5%). MicroRNA-155 level and cytokines were also reduced in curcumin-treated mice (p < 0.05).Conclusions: Curcumin’s ability to suppress LPS-induced inflammatory response may be due to the inhibition of miR-155.

Anti-Cytokine Activity of Curcumin and Its Binding to a Fragment of AβPP

Since it has been shown that Alzheimer’s disease is accompanied by higher peripheral concentrations of cytokines, we focused on the correction of chronic inflammation causing Aβ excess and aggregation what should have a positive impact. Proinflammatory cytokines action is realized by NF-κB intracellular signals. Curcumin can inhibit activation of the proinflammatory transcription factor NF-κB and is able to be mounted in the amyloid-β fibrils and encourage their disaggregation. To study the influence of anti-inflammatory effect of curcumin and its ability to model complexes with a fragment of AβPP. Investigation was carried out on rats with model of Alzheimer’s disease using nasal therapy with curcumin Concentration of cytokines in cerebral cortex, hippocampus and blood serum, and indicators of conditioned active escape reflex were determined in this study. Methods of molecular dynamics and docking were used to examine the interactions of curcumin with fragment of AβPP. Аβ42_Human in the hippocampus of rats provoked chronic neuroinflammation specifically and primarily at the injection site. Curcumin performance revealed specific depressing effect on cytokines in the cerebral cortex and in the hippocampus it appeared similar to the above, but of lower level. Anti-inflammatory activity of curcumin led to the recovery of memory parameters. Analysis of restriction sites of AβPP has shown that position of curcumin in Site II is energetically more favorable for binding. Our suggestion that curcumin is an effective anti-cytokine factor was confirmed by experimental results obtained in vivo and explain the mechanism describing its effect on NF-κB Curcumin doesn’t block the excision Aβ but binding with its hydrophobic region.

Curcumin: Towards molecularly targeted chemoprevention of cancer

Everybody is at risk for cancer yet environmental factors, lifestyle and diet as well as genetic factors influence the individual cancer risk. Targeted or personalized cancer prevention is based on the knowledge of the molecular characteristics of the tumor to be prevented, the molecular mechanisms of action of the compounds to be used and the genetic make-up of the person who opts for prevention medicine. Genetic factors are to a certain extent specific for cancer types or even subtypes as it has been shown for breast cancer. The growing knowledge of such genotype cancer risk associations will allow for the definition of personalized prevention strategies. Prevention in intermediate risk populations requires non-toxic, well tolerated and cheap compounds. The main activity of the polyphenol Curcumin is the inhibition of nuclear factor kappa B (NFkB) activation. NFkB is involved in many cancers where it acts through the generation of chronic inflammation that can be contrasted by the anti-inflammatory activity of Curcumin. Curcumin mediated inhibition of NFkB leads to the interruption of a pro-metastatic positive feedback loop where NFkB induces the expression of inflammatory cytokines which in turn promote NFkB activation and the transcription of NFkB regulated pro-metastatic factors such as COX2, SPARC, ALDH3A1 and EFEMP1. By interrupting this loop Curcumin significantly reduces the formation of metastases in murine breast and prostate cancer models. Clinical trials for primary prevention must rely on a risk based selection of participants and well characterized response markers. Targeted cancer prevention can be applied as primary prevention, after diagnosis in low risk situations where watchful waiting could be integrated by prevention drugs and after adjuvant therapy to contrast the remaining risk of relapse. Adequately targeted, cancer prevention approaches are expected to outperform the effects of current cancer therapy in terms of overall survival.

Antinociceptive and anti-inflammatory activities of Curcumin

Curcumin is a polyphenol derived from the herbal remedy and dietary spice turmeric (Curcuma longa) used by men in the exage as medicinal remedy and spice. In the last decades the curcumin has been an object of multiple studies in vitro and in vivo that have established the scientific bases of their numerous therapeutic activities, emphasizing their powerful anti-inflammatory, anti-cancer and antioxidant properties. In the present work a revision of the anti-inflammatory mechanisms of action is made that include the inhibition of several cell signalling pathways at multiple levels and downregulates cellular enzyme like cyclooxygenase, lipoxygenase and nitric oxide synthase. Also the preclinical and clinical studies that have been carried out in this aspect are mentioned, the support, safety and efficiency of the curcumin used with analgesic and antiinflammatory purposes.

Antioxidant and Antiinflammatory Activities of Curcumin on Diabetes Mellitus and its Complications

Antioxidant and Antiinflammatory Activities of Curcumin on Diabetes Mellitus and its Complications

Antioxidant and Antiinflammatory Activities of Curcumin on Diabetes Mellitus and its Complications

Diabetes mellitus (DM) has reached pandemic status and shows no signs of abatement. It can severely impair people's quality of life and affects patients all over the world. Since it is a serious, chronic metabolic disease, it can bring about many kinds of complications, which can in turn increase mortality. In recent decades, more and more studies have shown that oxidative stress and inflammatory reactions play critical roles in the pathogenesis of DM. There is an increasing demand for natural antidiabetic medicines that do not have the same side effects as modern drugs. Curcumin, a phytochemical found in the spice turmeric, has been used in India for centuries, and it has no known side effects. It has been shown to have some beneficial effects against various chronic illnesses. Many of these therapeutic actions can be attributed to its potent anti-oxidant and anti-inflammatory activities. In view of the oxidative stress and inflammatory mechanisms of DM, curcumin can be considered suitable for the prevention and amelioration of diabetes. In this review, we summarize the nosogenesis of DM, giving primary focus to oxidative stress and inflammation. We discuss the anti-oxidant and anti-inflammatory activities of curcumin in DM and its ability to mitigate the effects on DM and its associated complications in detail.

Vascular anti-inflammatory effects of curcumin on HMGB1-mediated responses in vitro

High mobility group box 1 (HMGB1) protein up-regulates proinflammatory cytokines in several inflammatory diseases. Curcumin is a polyphenol responsible for the yellow color of the curry spice turmeric. It possesses diverse pharmacological properties such as anti-inflammatory, anti-oxidant, anti-proliferative and anti-angiogenic activities. However, the effects of curcumin on HMGB1-mediated proinflammatory responses have not been studied. The anti-inflammatory activities of curcumin were determined by measuring solute flux, leukocyte adhesion and migration and activation of proinflammatory proteins in HMGB1-activated human umbilical vein endothelial cells. Curcumin inhibited the release of HMGB1 by lipopolysaccharide (LPS)- and HMGB1-mediated barrier disruption, neutrophil adhesion and migration, and expression of cell adhesion molecules. Further studies revealed that curcumin down-regulated the cell surface receptor of HMGB1 in human endothelial cells. These findings suggest that curcumin exerts anti-inflammatory effects in HMGB1-mediated proinflammatory responses, endorsing its usefulness as therapy for vascular inflammatory diseases.

Anti-Inflammatory Activity of Curcumin in Macrophages Stimulated by Lipopolysaccharides from Porphyromonas gingivalis

Background:Porphyromonas gingivalis, a major periodontopathic bacterium, is necessary for periodontitis to take place. The lipopolysaccharide (LPS) of P. gingivalis stimulates cytokine secretion in immune cells, and thereby initiates the inflammation related to periodontitis. Macrophages are the important ones of the immune cells that are prominent at inflammatory periodontal sites. Curcumin, a major curcumanoid found in the spice turmeric, exhibits anti-inflammatory properties. The aim of this study was to investigate the anti-inflammatory effect and the mechanism of action of curcumin in macrophages stimulated by P. gingivalis LPS. Methods: RAW264.7 cells pre-treated with various concentrations of curcumin were stimulated by P. gingivalis LPS. TNF-α and IL-1β expressions were separately detected by RT-PCR and ELISA. Next, activation of NF-ĸB-dependent transcription was examined by luciferase assay. Results: Curcumin dose-dependently inhibited TNF-α and IL-1β gene expression and protein synthesis in RAW264.7 cells stimulated with P. gingivalis LPS. P. gingivalis LPS activated NF-ĸB-dependent transcription in RAW264.7 cells, which were down-regulated by pre-treatment with curcumin as well. Conclusion: Our data suggest that curcumin can inhibit P. gingivalis LPS-induced cytokine expression, and that this could be due to the inhibition of the NF-ĸB pathway.