Antineoplastic and anticlastogenic properties of curcumin

Multifunctionality of Calebin A in inflammation, chronic diseases and cancer

Chronic diseases including cancer have high case numbers as well as mortality rates. The efficient treatment of chronic diseases is a major ongoing medical challenge worldwide, because of their complexity and many inflammatory pathways such as JNK, p38/MAPK, MEK/ERK, JAK/STAT3, PI3K and NF-κB among others being implicated in their pathogenesis. Together with the versatility of chronic disease classical mono-target therapies are often insufficient. Therefore, the anti-inflammatory as well as anti-cancer capacities of polyphenols are currently investigated to complement and improve the effect of classical anti-inflammatory drugs, chemotherapeutic agents or to overcome drug resistance of cancer cells. Currently, research on Calebin A, a polyphenolic component of turmeric (Curcuma longa), is becoming of growing interest with regard to novel treatment strategies and has already been shown health-promoting as well as anti-tumor properties, including anti-oxidative and anti-inflammatory effects, in diverse cancer cells. Within this review, we describe already known anti-inflammatory activities of Calebin A via modulation of NF-κB and its associated signaling pathways, linked with TNF-α, TNF-β and COX-2 and further summarize Calebin A's tumor-inhibiting properties that are known up to date such as reduction of cancer cell viability, proliferation as well as metastasis. We also shed light on possible future prospects of Calebin A as an anti-cancer agent.

Microneedles Assisted Controlled and Improved Transdermal Delivery of High Molecular Drugs via Insitu Forming Depot Thermoresponsive Poloxamers Gels in Skin Microchannels

Skin considered as an attractive route for variety of drug molecules administration. However it proved to be the main physical barrier for drug flux owing to their poor permeability and low bioavailability across stratum corneum layer. In current study novel approach has been used to enhance transdermal delivery via microporation through combination of poloxamers gels and microneedles arrays. The phase transition of poloxamers at various concentrations from sol-gel was evaluated using AR2000 rheometer to confirm microneedles-assisted insitu forming depots. Temperature test confirmed gelation between 32-37 °C. Curcumin was loaded in poloxamer formulations at variable concentrations and its effect showed reduction in critical gelation temperature (CGT) owing to its hydrophobic nature. Microneedles (MNs) arrays (600 µm) prepared from Gantrez S-97, PEG 10000 and Gelatin B using (19 × 19) laser-engineered silicone micromoulds showed high mechanical stability investigated via Texture analyzer. From insitu dissolution profile Gelatin 15% w/w based MNs displayed quicker dissolution rate in comparison to PG10000. VivoSight® OCT scanner and dye tracking confirmed that PG10000 MNs arrays pierced SC layer, infiltrate the epidermis and goes to dermis layer. From invitro permeation, it was concluded that 20% w/w PF127^® gel formulations containing (0.1% and 0.3%) curcumin displayed high curcumin permeation for comparatively longer time through microporated skin samples in comparison to non-microporated skin. The curcumin distribution in skin tissues with higher florescence intensity was noted in MNs treated skin samples by confocal microscopy. FTIR confirmed the structure formation of fabricated MNs, while TGA showed dry, brittle and rigid nature of Gelatin MNs.

The Role of Reactive Oxygen Species in Tumor Treatment and its Impact on Bone Marrow Hematopoiesis

Reactive oxygen species (ROS), an important molecule inducing oxidative stress in organisms, play a key role in tumorigenesis, tumor progression and recurrence. Recent findings on ROS have shown that ROS can be used to treat cancer as they accelerate the death of tumor cells. At present, pro-oxidant drugs that are intended to increase ROS levels of the tumor cells have been widely used in the clinic. However, ROS are a double-edged sword in the treatment of tumors. High levels of ROS induce not only the death of tumor cells but also oxidative damage to normal cells, especially bone marrow hemopoietic cells, which leads to bone marrow suppression and (or) other side effects, weak efficacy of tumor treatment and even threatening patients' life. How to enhance the killing effect of ROS on tumor cells while avoiding oxidative damage to the normal cells has become an urgent issue. This study is a review of the latest progress in the role of ROS-mediated programmed death in tumor treatment and prevention and treatment of oxidative damage in bone marrow induced by ROS.

A difunctional Pluronic®127-based in situ formed injectable thermogels as prolonged and controlled curcumin depot, fabrication, in vitro characterization and in vivo safety evaluation

Curcumin has been reported to be used widely against many types of pathological conditions in clinics. However, due to its limitations such as poor solubility, poor oral absorption and low stability have limited its applications. In the current study, a series of novel chemically cross-linkable depot gel formulations were developed based on thermoresponsive micellar polymer (Pluronic^®127) with polyelectrolyte hydrophilic monomer, that is, 2-acrylamido-2-methylpropane sulfonic acid by cold and in situ grafting polymerization method. The formulations were aimed to deliver curcumin at controlled rate from in situ formed depot after administration through subcutaneous route in vivo. The sol-gel phase transitions of formulations were observed by rheological analysis, tube titling and optical transmittance measurements. Maximum swelling of gel formulations was observed at pH 7.4 and below CGT, that is, 25 °C. The in vitro release profile exhibits maximum drug release at pH 7.4 and 25 °C owing to relaxed gel state. In vitro degradation profile of gel formulations showed controlled degradation rate. Cell growth inhibition study confirmed the biocompatibility and safe nature of bare gel formulations against L929 cell lines. In vitro cytotoxic study showed that curcumin loaded in gel formulation has controlled pharmacological activity against HeLa and MCF-7 cancer cells as compared to free drug solution. The IC₅₀ values calculated for pure curcumin solution (30 ± 0.77 µg/ml for HeLa and 27 ± 0.39 µg/ml for MCF-7) were found higher in comparison to curcumin-loaded thermogels against HeLa (19 ± 0.28 µg/ml and 23 ± 0.81 µg/ml) and MCF-7 (22 ± 0.54 µg/ml and 21 ± 0.49 µg/ml). Histopathological and hematological analysis showed the biocompatible nature of hydrogels. Structural confirmation was done by Fourier transform infrared spectroscopy (FTIR) and proton nuclear magnetic resonance spectroscopy (¹H NMR). Differential scanning calorimetry (DSC) and thermogravimetric analysis (TGA) confirmed the thermal stability of the gel formulation. The porous structure of gel formulations was assessed by scanning electron microscopic (SEM) analysis. Results concluded that newly developed gel formulations have thermoresponsive behavior with phase transition at body temperature and can be used as in situ controlled drug depot.

Modulatory effect of curcumin against genotoxicity and oxidative stress induced by cisplatin and methotrexate in male mice

The use of dietary antioxidants to modulate the toxic side effects induced by the anticancer drugs used in chemotherapy is currently eliciting considerable interest. This study was undertaken to investigate the possible protective role of the antioxidant curcumin (CMN) against genotoxicity, cytotoxicity and oxidative stress induced by cisplatin and methotrexate. Male mice were administered CMN orally in the dosages of 60, 90, and 120 mg/kg for three consecutive days before a single intraperitoneal injection of either cisplatin (6.5 mg/kg) or methotrexate (10 mg/kg). Animals were sacrificed 24 h after treatment with the used anticancer drugs. The protective role of CMN against the genotoxic and cytotoxic effects of the tested anticancer drugs was evaluated by using micronucleus and comet assay. The oxidative stress induced by the two anticancer drugs was assessed by determining malondialdehyde and reduced glutathione levels in kidney tissues. The results indicated that CMN pretreatment at the tested doses reduced the incidence of micronuclei and DNA damage induced by cisplatin and methotrexate. Moreover, malondialdhyde level was significantly decreased while glutathione level was significantly increased in CMN pretreated groups compared with cisplatin- and methotrexate-treated groups. This protective effect of CMN could be attributed to its ability to scavenge reactive oxygen species.

Curcumin loaded pH-sensitive hybrid lipid/block copolymer nanosized drug delivery systems

Curcumin is a perspective drug candidate with pleiotropic antineoplastic activity, whose exceptionally low aqueous solubility and poor pharmacokinetic properties have hampered its development beyond the preclinical level. A possible approach to overcome these limitations is the encapsulation of curcumin into nano-carriers, incl. liposomes. The present contribution is focused on feasibility of using hybrid pH-sensitive liposomes, whereby curcumin is entrapped as a free drug and as a water soluble inclusion complex with PEGylated tert-butylcalix[4]arene, which allows the drug to occupy both the phospholipid membranes and the aqueous core of liposomes. The inclusion complexes were encapsulated in dipalmithoylphosphathydilcholine:cholesterol liposomes, whose membranes were grafted with a poly(isoprene-b-acrylic acid) diblock copolymer to confer pH-sensitivity. The liposomes were characterized by DLS, ζ-potential measurements, cryo-TEM, curcumin encapsulation efficacy, loading capacity, and in vitro release as a function of pH. Free and formulated curcumin were further investigated for cytotoxicity, apoptosis-induction and caspase-8, and 9 activation in chemosensitive HL-60 and its resistant sublines HL-60/Dox and HL-60/CDDP. Formulated curcumin was superior cytotoxic and apoptogenic agent vs. the free drug. The mechanistic assay demonstrated that the potent proapoptotic effects of pH-sensitive liposomal curcumin presumably mediated via recruitment of both extrinsic and intrinsic apoptotic pathways in both HL-60 and HL-60/CDDP cells.

Cytotoxic effect of the biotechnologically-derived justicidin B on human lymphoma cells

Purpose of work: The study was aimed to assess the antineoplastic activity of justicidin B in vitro and to search for its general toxicological profile in vivo. The anti-neoplastic activity of the arylnaphthalene lignin, justicidin B, was assessed in a panel of human lymphoma cell lines and compared with etoposide as a reference compound. A screening of the cytotoxicity after 24, 48 and 72 h exposure was performed by the MTT-dye reduction assay. Dose- and time-dependent cytotoxic effect was observed and the IC50 values ranged from 0.17 µM (RPMI-8226, 72 h) to 183 µM (U-266, 24 h) and more than 200 µM (HD-MY-Z, 24 and 48 h). Activation of caspase 3 and 8 was involved in the induction of programmed cell death in DOHH-2 cell line. NF-κB modulation occurred in DOHH-2 and HH cells. The general toxicity in mice after i.p. injection was also tested. The highest applied dose (50 mg/kg = 137.25 µM) did not show any toxicity. Justicidin B possesses definite and potent selective antineoplastic activity, related to its ability to induce programmed cell death in NHL-derived human cell lines at concentrations that can be reached in mice without toxicity.

Comparative in vivo evaluations of curcumin and its analog difluorinated curcumin against cisplatin-induced nephrotoxicity

Curcumin, a polyphenol, has pharmacological effects including antioxidant, anti-inflammatory and anti-cancer features. In this study, we have performed comparative in vivo evaluations of CDF (curcumin difluorinated) and curcumin in cisplatin-induced nephrotoxicity in rats. Male Wistar rats were divided into four groups: (1) Control; (2) Cisplatin (7 mg/kg body wt, intraperitoneal as a single dose); (3) Cisplatin and CDF (50 mg/rat/day; for 12 days); (4) Cisplatin and curcumin (50 mg/rat/day), for 12 days). Cisplatin treated rats exhibited kidney injury manifested by increased serum N-urea and creatinine (P < 0.001). Kidney from cisplatin treated rats also exhibited significant increase in malondialdehyde (MDA) and 8-isoprostane levels (P < 0.001). Treatment with CDF and curcumin prevented the rise in serum N-urea, creatinine, MDA and 8-isoprostane as compared to experimental control group in kidney (P < 0.05). Compared to curcumin, CDF had greater potential in suppressing cisplatin-induced pro-inflammatory factors NF-κB and COX-2 as well as downstream markers Nrf2 and HO-1 (P < 0.05) in kidney. The analysis on anion transport markers (OAT1 and OAT3) showed a similar trend (CDF > curcumin). CDF could reduce the expression of multi-drug resistance markers OCT1, OCT2, MRP2 and MRP4 to a much greater extent than curcumin (P < 0.05). We also demonstrate that CDF influenced the expression of p-mTOR, p-p70S6K1, p-4E-BP1 and p-Akt. These data suggest that CDF can potentially be used to reduce the chemotherapy induced nephrotoxicity thereby enhancing the therapeutic window of cisplatin. The results also proved that compared to curcumin, CDF has superior protective effect in nephrotoxicity.

The Indian Spice Turmeric Delays and Mitigates Radiation-Induced Oral Mucositis in Patients Undergoing Treatment for Head and Neck Cancer: An Investigational Study

PURPOSE

Radiation-induced oral mucositis is an acute morbidity seen in patients undergoing treatment for head and neck cancers. In this study, we evaluated the efficacy of turmeric in preventing radiation-induced mucositis.

METHODS

This was a single-blinded, randomized, controlled clinical trial and was conducted with head and neck cancer patients requiring 70 Gy of radiation or chemoradiotherapy (daily radiotherapy plus carboplatin once a week). Eligible patients (n = 80) were randomly assigned to receive either turmeric gargle (n = 40) or povidone-iodine ([n = 40] active comparator condition) during chemo/radiotherapy during the period of treatment. Oral mucositis was assessed using the RTOG (Radiation Therapy Oncology Group) grading system before the start, during, and at the end of the treatment by an investigator unaware of the treatment. The primary endpoint of this study was the incidence of mucositis every week during the 7-week period. The secondary endpoint was the effect of turmeric gargle on the incidence of treatment breaks, loss of scheduled treatment days, and decrease in body weight at the end of the treatment.

RESULTS

This study clearly suggests that when compared with the cohorts using povidone-iodine gargle, the group using turmeric as a mouthwash had delayed and reduced the levels of radiation-induced oral mucositis and was statistically significant at all time points (P< 0.001 toP< 0.0001). Additionally, the cohorts using turmeric had decreased intolerable mucositis (P< 0.001) and lesser incidence of treatment breaks in the first half of the treatment schedule before 4 weeks (P< 0.01) and reduced change in body weight (P< 0.001).

CONCLUSIONS

Gargling with turmeric by head and neck cancer patients undergoing radiation therapy provided significant benefit by delaying and reducing the severity of mucositis. Turmeric is readily available, relatively inexpensive, and highly accepted making it useful in cancer treatment.

Curcumin protection activities against γ-rays-induced molecular and biochemical lesions

Background

Curcumin is a yellow-pigment phenolic compound used as a food spice and has a broad spectrum of antioxidant, anti-carcinogenic, anti-mutagenic and anti-inflammatory properties.

Methods

Radio-protective efficacy of curcumin; diferuloylmethane (C₂₁H₂₀O₆) was evaluated using molecular and biochemical assays in male mice after exposure to 3 Gy γ-rays. Curcumin was given at a dose of 400 μmol/ kg body weight via gastric tubes for 5 following days either pre-, post- or both pre- and post-exposure.

Results

The incidence of aberrant cells and aberration types (mostly chromatids, breaks and fragments) was reduced with curcumin dosage as compared to irradiated group. Thiobarbituric acid reactive substances (TBARS), hydroperoxide (HP), xanthine oxidase (XO) and apoptotic markers (DNA- fragmentation and caspase-3 activation) were increased significantly, whereas levels of glutathione (GSH) and the enzymatic antioxidants [Superoxide dismutase (SOD), catalase (CAT) and glutathione peroxidase (GPx)] were significantly depleted in γ-irradiated mice. Curcumin treatments of mice groups including the 5 days pre-irradiation treated group (protected), the 5 days post-irradiation treated group (treated), and the curcumin treated group 5 days pre- and post-irradiation (protracted), have attenuated the liver toxic effects of γ-rays as manifested by reducing the levels of TBARS, HP, XO and DNA fragmentation. Curcumin has also rescued the depletion of GSH and the enzymatic-antioxidant status.

Conclusions

Curcumin has significant radio-protective and radio-recovery activities in γ-irradiated mice. It has antioxidant potential against γ-rays-induced cytogenetic, molecular and biochemical lesions in mice.

Discovery of curcumin, a component of golden spice, and its miraculous biological activities

1. Curcumin is the active ingredient of the dietary spice turmeric and has been consumed for medicinal purposes for thousands of years. Modern science has shown that curcumin modulates various signalling molecules, including inflammatory molecules, transcription factors, enzymes, protein kinases, protein reductases, carrier proteins, cell survival proteins, drug resistance proteins, adhesion molecules, growth factors, receptors, cell cycle regulatory proteins, chemokines, DNA, RNA and metal ions. 2. Because of this polyphenol's potential to modulate multiple signalling molecules, it has been reported to possess pleiotropic activities. First demonstrated to have antibacterial activity in 1949, curcumin has since been shown to have anti-inflammatory, anti-oxidant, pro-apoptotic, chemopreventive, chemotherapeutic, antiproliferative, wound healing, antinociceptive, antiparasitic and antimalarial properties as well. Animal studies have suggested that curcumin may be active against a wide range of human diseases, including diabetes, obesity, neurological and psychiatric disorders and cancer, as well as chronic illnesses affecting the eyes, lungs, liver, kidneys and gastrointestinal and cardiovascular systems. 3. Although many clinical trials evaluating the safety and efficacy of curcumin against human ailments have already been completed, others are still ongoing. Moreover, curcumin is used as a supplement in several countries, including India, Japan, the US, Thailand, China, Korea, Turkey, South Africa, Nepal and Pakistan. Although inexpensive, apparently well tolerated and potentially active, curcumin has not been approved for the treatment of any human disease. 4. In the present article, we discuss the discovery and key biological activities of curcumin, with a particular emphasis on its activities at the molecular and cellular levels, as well as in animals and humans.

In vitro cytogenetic and genotoxic effects of curcumin on human peripheral blood lymphocytes

Curcumin has shown a wide range of properties such as anti-inflammatory and anti-carcinogenic properties. Many of these effects, mainly the anti-carcinogenic effect, could be linked to its anti-oxidant effects. Nevertheless, some studies suggest that this natural compound possesses both pro- and anti-oxidative effects and that curcumin could be a genotoxic agent for some cell lines. We evaluated the genetic damage induced by curcumin to human lymphocytes exposed to increasing concentrations (0-50 μg/ml) of curcumin. Biomarkers such as chromosome aberrations (CAs) and sister chromatid exchange (SCE) were analyzed. In addition to the cytogenetic analysis, the effect of curcumin in the cell proliferation kinetics (CPK) by the proliferation index (PI) was also analyzed. The results indicated that high concentrations of curcumin induced CAs, mainly acentric fragments. SCEs rate was not statistically different from the control group in any curcumin treated cell group. The PI of cells treated with 2 and 5 μg/ml of curcumin were statistically significant from the control group and finally, the MI showed a tendency to increase in all the concentrations of curcumin tested. In conclusion, it can be assumed that the higher concentrations of curcumin evaluated have a cyto and genotoxic effect, in vitro, for human peripheral lymphocytes.

Erucylphospho-N,N,N-trimethylpropylammonium shows substantial cytotoxicity in multiple myeloma cells

Multiple myeloma (MM) is a frequent hematological malignancy that is incurable despite recent developments, such as proteasome and angiogenic inhibitors. Erucylphospho-N,N,N-trimethylpropylammonium (erufosine) is an i.v. injectable alkylphosphocholine with antineoplastic activity based on an unusual mode of action and is currently undergoing clinical trials in leukemia patients. The aim of this investigation was to evaluate the efficacy of erufosine in MM cells and to study the modulation of cell-death pathways. The cytotoxicity of erufosine against three MM cell lines (RPMI-8226, U-266, and OPM-2) was determined by the 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide-dye reduction assay. All MM cell lines responded to erufosine, RPMI-8226 cells being most and U-266 being least sensitive. The respective IC(50) values were 3.2 and 16.2 micromol/L. Various cell-death characteristics were studied in response to erufosine, such as morphological changes, oligonucleosomal DNA fragmentation, caspase activation, and poly (ADP)-ribose polymerase cleavage. Erufosine was found to cause cell shrinkage, chromatin condensation, and caspase-8 and -3 activation. Taken together, our data indicate that erufosine is a potential antimyeloma drug eliciting specific features of apoptotic cell death in vitro.

In vivo growth inhibitory and anti-angiogenic effects of synthetic novel dienone cyclopropoxy curcumin analogs on mouse Ehrlich ascites tumor

In the present study, four novel dienone cyclopropoxy curcumin analogs 1a-4a were synthesized by nucleophillic substitution reaction with cyclopropyl bromide. The tumor inhibitory and anti-angiogenic effects of the synthetic compounds were studied on mouse Ehrlich ascites tumor (EAT) in vivo. The compounds 1a-4a increased the life span (% ILS) of EAT bearing mice with corresponding significant reduction in ascites volume and cell number and induced apoptotic bodies in EAT cells. Anti-angiogenic studies of the compounds demonstrated significant reduction of microvessel density (MVD) in the peritoneum wall sections of mice and induced avascular zone in CAM model. Our findings demonstrate that the tumor growth inhibitory effects of synthetic dienone cyclopropoxy curcumin analogs 1a-4a could be mediated by promoting apoptosis and inhibiting tumor angiogenesis. However, the compounds need to be explored further to assess its clinical relevance.