Bisdemethoxycurcumin inhibits PDGF-induced vascular smooth muscle cell motility and proliferation

Subjective biosafety assessment of bisdemethoxycurcumin from the rhizomes of Curcuma longa

Introduction/Background: Curcuma longa, a plant native to the Indian subcontinent has a variety of biological activities. Curcumin is the most abundant and biologically active compound with many therapeutic properties. Demethoxycurcumin (DMC) and bisdemethoxycurcumin (BDMC) - the two other bioactive components present in Curcuma longa, besides curcumin, are collectively termed curcuminoids. Apart from the well-known curcumin, BDMC also has been reported to possess promising biological and pharmacological effects, but very little scientific evidence on its safety assessment has been published.Objective: The present study was undertaken to determine the safety of pure BDMC from Curcuma longa extract in rodents which comprises of general toxicity (both four weeks and three months duration), reproductive/developmental toxicity and genotoxicity studies.Methods: The Good Laboratory Practice studies were carried out in accordance with the test guidelines established by the Organization for Economic Cooperation and Development.Results: No treatment-related adverse findings were seen in general toxicity testing and a no observed adverse effect level (NOAEL) of 1000 mg/kg/day was established after four weeks (sub-acute) and three-months (sub-chronic) dosing. Evaluation of fertility, embryo-fetal, and post-natal reproductive and developmental parameters also showed no adverse findings with a NOAEL of 1000 mg/kg/day established. The results of genotoxicity as evaluated by in vitro reverse mutation assay, and in vivo micronucleus test in mice indicate that BDMC did not induce any genotoxic effects.Conclusion: Oral administration of BDMC is safe in rodents and non-mutagenic, with no adverse effects under experimental conditions.

M, Thazhathidath S. Assessment of Safety Profile of Activated Curcumin C3 Complex (AC3®), Enriched Extract of Bisdemethoxycurcumin from the Rhizomes of Curcuma longa

The present work was carried out to investigate the toxic effects of Activated Curcumin C3 Complex (AC3®) through the methods of acute, subacute, subchronic, reproductive/developmental toxicity, and genotoxicity when administered orally in experimental rodents. The studies were carried out in line with OECD principles of good laboratory practice. A single-dose acute oral toxicity study was conducted on female Wistar rats that produced no toxic effects after 14 days (the observation period) of treatment. Subacute, subchronic, and reproductive/developmental studies were conducted in Wistar rats, divided equally into vehicle control, 125, 250, and 500 mg/kg dose groups along with recovery groups for vehicle control and high dose. In all the studies, there were no abnormal clinical signs/behavioral changes, reproductive and developmental parameters, or gross and histopathological changes. Likewise, no alteration was found in the body weight, hematology, and other biochemical parameters. Also, it did not show mutagenicity in the in vitro AMES test or clastogenicity and aneugenicity in the in vivo micronucleus test, indicating that AC3® did not induce any genotoxic effects. This revealed that oral administration of AC3® is safe in rodents, nonmutagenic, and had no observed adverse effects under experimental conditions.

Benefits of Curcumin in the Vasculature: A Therapeutic Candidate for Vascular Remodeling in Arterial Hypertension and Pulmonary Arterial Hypertension?

Growing evidence suggests that hypertension is one of the leading causes of cardiovascular morbidity and mortality since uncontrolled high blood pressure increases the risk of myocardial infarction, aortic dissection, hemorrhagic stroke, and chronic kidney disease. Impaired vascular homeostasis plays a critical role in the development of hypertension-induced vascular remodeling. Abnormal behaviors of vascular cells are not only a pathological hallmark of hypertensive vascular remodeling, but also an important pathological basis for maintaining reduced vascular compliance in hypertension. Targeting vascular remodeling represents a novel therapeutic approach in hypertension and its cardiovascular complications. Phytochemicals are emerging as candidates with therapeutic effects on numerous pathologies, including hypertension. An increasing number of studies have found that curcumin, a polyphenolic compound derived from dietary spice turmeric, holds a broad spectrum of pharmacological actions, such as antiplatelet, anticancer, anti-inflammatory, antioxidant, and antiangiogenic effects. Curcumin has been shown to prevent or treat vascular remodeling in hypertensive rodents by modulating various signaling pathways. In the present review, we attempt to focus on the current findings and molecular mechanisms of curcumin in the treatment of hypertensive vascular remodeling. In particular, adverse and inconsistent effects of curcumin, as well as some favorable pharmacokinetics or pharmacodynamics profiles in arterial hypertension will be discussed. Moreover, the recent progress in the preparation of nano-curcumins and their therapeutic potential in hypertension will be briefly recapped. The future research directions and challenges of curcumin in hypertension-related vascular remodeling are also proposed. It is foreseeable that curcumin is likely to be a therapeutic agent for hypertension and vascular remodeling going forwards.

Glossogyne tenuifolia Attenuates Proliferation and Migration of Vascular Smooth Muscle Cells

The proliferation and migration of vascular smooth muscle cells (VSMCs) are essential in the pathogenesis of various vascular diseases, such as atherosclerosis and restenosis. Among the mediators of VSMC during atherosclerosis development, platelet-derived growth factor (PDGF)-BB is a potent mitogen for VSMCs and greatly contributes to the intimal accumulation of VSMCs. Glossogyne tenuifolia (GT, Xiang-Ru) is a traditional antipyretic and hepatoprotective herb from Penghu Island, Taiwan. This study evaluated the inhibitory effect of GT ethanol extract (GTE) and GT water extract (GTW) on proliferative and migratory activities in PDGF-BB-induced VSMCs. The experimental results demonstrated that GTE significantly inhibited the PDGF-BB-stimulated VSMC proliferation and migration, as shown by MTT, wound healing, and Boyden chamber assays. GTE was found to have a much more potent inhibitory activity than GTW. Based on the Western blot analysis, GTE significantly blocked the PDGF-BB-induced phosphorylation of NF-κB and mitogen-activated protein kinase (MAPK) pathways, including extracellular signal-regulated kinase (ERK), p38, and JNK, in VSMCs. In addition, GTE retarded the PDGF-BB-mediated migration through the suppression of matrix metalloproteinase (MMP)-2 and MMP-9 expression in VSMCs. Three main ingredients of GT-chlorogenic acid, luteolin-7-glucoside, and luteolin-all showed significant anti-proliferative effects on PDGF-BB-induced VSMCs. As a whole, our findings indicated that GTE has the potential to be a therapeutic agent to prevent or treat restenosis or atherosclerosis.

Enhanced oral bioavailability of Bisdemethoxycurcumin-loaded self-microemulsifying drug delivery system: Formulation design, in vitro and in vivo evaluation

In this study, we sought to overcome the poor solubility and bioavailability of bismethoxycurcumin (BDMC) by fabricating a BDMC-loaded self micro-emulsifying system (BDMC-SMEDDS). Solubility and compatibility tests, pseudo-ternary phase diagrams (PTPDs) as well as d-optimal concept was applied to design the formulation. The assessment of the prepared BDMC-SMEDDS in-vitro mainly included droplet size (DS) and entrapment efficiency (EE) determination, morphology, drug release and stability testing. Besides, the in vivo behavior was also evaluated after oral administration of BDMC-SMEDDS to rats. The optimal formulation was found to compose of Kolliphor EL (K-EL, emulsifier, 645.3 mg), PEG 400 (co-emulsifier, 147.2 mg), ethyl oleate (EO, oil, 207.5 mg) and BDMC (50 mg). The BDMC-SMEDDS with satisfactory stability had a mean size of 21.25 ± 3.23 nm and EE of 98.31 ± 0.32%. Roughly 70% of BDMC was released from BDMC-SMEDDS within 84 h compared with <20% from the free BDMC. More importantly, the in-vivo behavior of BDMC-SMEDDS showed that the AUC_(0-12h) and plasma concentration of BDMC increased substantially as compared to the free BDMC. Altogether, BDMC-SMEDDS has the potential to enhance the solubility and bioavailability of BDMC and could be applied in the clinics.

Curcumin induced oxidative stress attenuation by N-acetylcysteine co-treatment: a fibroblast and epithelial cell in-vitro study in idiopathic pulmonary fibrosis

Background

Idiopathic Pulmonary Fibrosis (IPF) is a fatal lung disease of unknown etiology with only two federally approved drug options. Given the complex molecular pathogenesis of IPF involving multiple cell types and multiple pathways, we explore the effects of a potential antifibrotic and antioxidant drug combination. Curcumin is a polyphenolic compound derived from turmeric with significant biological activity including a potential antifibrotic capacity. N-acetylcysteine (NAC) is a precursor to the antioxidant glutathione. To advance our understanding of these molecules, and to identify a clinical application, we present a small number of focused experiments that interrogates the effect of curcumin and NAC on pathways relevant to IPF in both fibroblasts and epithelial cells.

Methods

Primary epithelial cell and fibroblasts isolated from patients with IPF were challenged with a combination treatment of NAC and curcumin. Evaluation of the antifibrotic potential and effect on oxidative stress was performed through QPCR gene expression analysis and functional assays including scratch tests, viability assays, and measurement of induced reactive oxygen species.

Results

We demonstrate that curcumin alone does have antifibrotic potential, but that effect is accompanied by proapoptotic increases in oxidative stress. Coupled with this, we find that NAC alone can reduce oxidative stress, but that epithelial cell viability is decreased through this treatment. However, co-administration of these two molecules decreases oxidative stress and maintains high cell viability in both cell types. In addition, this co-treatment maintains an antifibrotic potential.

Conclusions

These findings suggest a novel application for these molecules in IPF and encourage further exploration of this potential therapeutic approach.

Preparation of poly(lactide-co-glycolide) microspheres and evaluation of pharmacokinetics and tissue distribution of BDMC-PLGA-MS in rats

The aim of the present study was to develop a novel long-acting Poly (lactic-co-glycolic acid) (PLGA)-based microspheres formulation of Bisdemethoxycurcum (BDMC) by emulsion-solvent evaporation method. Meanwhile, the effects of the volume ratio of the dispersed phase and continuous phase, the concentration of PLGA and PVA, the theoretical drug loading and stirring speed were investigated. The mean diameter of the microspheres was 8.5 µm and the size distribution was narrow. The encapsulation efficiency (EE) and drug loading efficiency (DLE) of BDME loaded PLGA microspheres (BDMC-PLGA-MS) was 94.18% and 8.14%, respectively. In an in vitro study of drug release, it can be concluded that the BDMC-PLGA-MS exhibited sustained and long-term release properties for 96 h. Stability studies suggested that the microspheres we prepared had a very good stability. Furthermore, the results of an in vivo study indicated that the BDMC-PLGA-MS had sustained release effect and was mainly distributed in the lung tissue, and less distribution in other tissues, which indicated that microspheres could be an effective parenteral carrier for the delivery of BDMC in lung cancer treatment.

A novel PDGF receptor inhibitor-eluting stent attenuates in-stent neointima formation in a rabbit carotid model

A novel drug-eluting stent (DES) is required to target vascular smooth muscle cells (SMCs) without harming endothelial cells (ECs). Platelet-derived growth factor (PDGF) is critical for the proliferation and migration of SMCs. Sunitinib [a PDGF receptor (PDGFR) tyrosine kinase inhibitor]‑eluting stents may therefore inhibit neointimal formation. The aim of the present study was to examine the stent‑based delivery of sunitinib in a rabbit carotid model; in addition, the effects of sunitinib were evaluated in vitro. Local administration of sunitinib markedly reduced neointimal formation without delaying re-endothelialization in the carotid artery model. In vitro, sunitinib inhibited SMC proliferation; however, no effects were observed on ECs. Sunitinib caused necrosis of SMCs. In addition, sunitinib attenuated PDGF-stimulated SMC migration in a scratch wound assay and inhibited α‑SMA cytoskeleton polymerization. Furthermore, sunitinib inhibited PDGF-induced phosphorylation of extracellular signal-regulated kinase in vitro and in vivo. Therefore, this novel DES may be a potential strategy for the treatment of vascular disorders.

Bisdemethoxycurcumin-induced S phase arrest through the inhibition of cyclin A and E and induction of apoptosis via endoplasmic reticulum stress and mitochondria-dependent pathways in human lung cancer NCI H460 cells

Curcuminoids are the major natural phenolic compounds found in the rhizome of many Curcuma species. Curcuminoids consist of a mixture of curcumin, demethoxycurcumin (DMC), and bisdemethoxycurcumin (BDMC). Although numerous studies have shown that curcumin induced cell apoptosis in many human cancer cells, however, mechanisms of BDMC-inhibited cell growth and -induced apoptosis in human lung cancer cells still remain unclear. Herein, we investigated the effect of BDMC on the cell death via the cell cycle arrest and induction of apoptosis in NCI H460 human lung cancer cells. Flow cytometry assay was used to measure viable cells, cell cycle distribution, the productions of reactive oxygen species (ROS) and Ca²⁺ , mitochondrial membrane potential (ΔΨ_m ) and caspase-3, -8 and -9 activity. DNA damage and condension were assayed by Comet assay and DAPI staining, respectively. Western blotting was used to measure the changes of cell cycle and apoptosis associated protein expressions. Results indicated that BDMC significantly induced cell death through induced S phase arrest and induced apoptosis. Moreover, DMC induced DNA damage and condension, increased ROS and Ca²⁺ productions and decreased the levels of ΔΨ_m and promoted activities caspase-3, -8, and -9. Western blotting results showed that BDMC inhibited Cdc25A, cyclin A and E for causing S phase arrest, furthermore, promoted the expression of AIF, Endo G and PARP and the levels of Fas ligand (Fas L) and Fas were also up-regulated. Results also indicated that BDMC increased ER stress associated protein expression such as GRP78, GADD153, IRE1α, IRE1β, ATF-6α, ATF-6β, and caspase-4. Taken together, we suggest that BDMC induced cell apoptosis through multiple signal pathways such as extrinsic, intrinsic and ES tress pathway. © 2015 Wiley Periodicals, Inc. Environ Toxicol 31: 1899-1908, 2016.

Phenotypic transformation of smooth muscle cells from porcine coronary arteries is associated with connexin 43

The current study aimed to investigate the relevance of the gap junction protein connexin Cx43 in coronary artery smooth muscle cell (SMC) heterogeneity and coronary artery restenosis. SMCs were isolated from the coronary artery of 3‑month‑old pigs using enzymatic digestion. Two distinct SMC populations were isolated: Rhomboid (R) and spindle‑shaped (S) cells. S‑SMCs exhibited relatively lower rates of proliferation, exhibiting a classic ''hills‑and valleys'' growth pattern; R‑SMCs displayed increased proliferation rates, growing as mono‑ or multi‑layers. Immunofluorescent staining, polymerase chain reaction and western blotting were used to assess the expression of Cx40 and Cx43 in SMCs. For further evaluation, cultured SMCs were treated with 10 ng/ml platelet‑derived growth factor (PDGF)‑BB with or without the gap junction blocker 18α‑glycyrrhetinic acid. Stent‑induced restenosis was assessed in vivo. Different expression patterns were observed for Cx40 and Cx43 in R‑ and S‑SMCs. Cx40 was the most abundant Cx in S‑SMCs, whereas CX43 was identified at relatively higher levels than Cx40 in R‑SMCs. Notably, PDGF‑BB converted S‑SMCs to R‑SMCs, with increased Cx43 expression, while 18α‑glycyrrhetinic acid inhibited the PDGF‑BB‑induced phenotypic alterations in S‑SMCs. Additionally, restenosis was confirmed in pigs 1‑month subsequent to stent placement. R‑SMCs were the major cell population isolated from stent‑induced restenosis artery tissues, and exhibited markedly increased Cx43 expression, in accordance with the in vitro data described above. In conclusion, the phenotypic transformation of coronary artery SMCs is closely associated with Cx43, which is involved in restenosis. These observations provide a basis for the use of Cx43 as a novel target in restenosis prevention.

Magnobovatol inhibits smooth muscle cell migration by suppressing PDGF-Rβ phosphorylation and inhibiting matrix metalloproteinase-2 expression

The migration of vascular smooth muscle cells (VSMCs) may play a crucial role in the pathogenesis of vascular diseases, such as atherosclerosis and post-angioplasty restenosis. Platelet-derived growth factor (PDGF)-BB is a potent mitogen for VSMCs and plays an important role in the intimal accumulation of VSMCs. Magnobovatol, a new neolignan from the fruits of Magnolia obovata, has been shown to have anticancer properties. However, the effects of magnobovatol on VSMCs are unknown. In the present study, we examined the effects of magnobovatol on the PDGF-BB-induced migration of mouse and human VSMCs, as well as the underlying mechanisms. Magnobovatol significantly inhibited the PDGF-BB-induced migration of mouse and human VSMCs without inducing cell death (as shown by MTT assay and wound healing assay). Additionally, we demonstrated that magnobovatol significantly blocked the PDGF-BB-induced phosphorylation of the PDGF receptor (PDGF-R), Akt and extracellular signal-regulated kinase (ERK)1/2 by inhibiting the activation of the PDGF-BB signaling pathway. Moreover, in both mouse and human VSMCs, magnobovatol inhibited PDGF-induced matrix metalloproteinase (MMP)-2 expression at the mRNA and protein level, as well as the proteolytic activity of MMP-2 (as shown by western blot analysis, RT-PCR, gelatin zymography and ELISA). In addition, the sprout outgrowth formation of aortic rings induced by PDGF-BB was inhibited by magnobovatol (as shown by aortic ring assay). Taken together, our findings indicate that magnobovatol inhibits VSMC migration by decreasing MMP-2 expression through PDGF-R and the ERK1/2 and Akt pathways. Our data may improve the understanding of the anti-atherogenic effects of magnobovatol in VSMCs.

Phytochemical Compounds and Protection from Cardiovascular Diseases: A State of the Art

Cardiovascular diseases represent a worldwide relevant socioeconomical problem. Cardiovascular disease prevention relies also on lifestyle changes, including dietary habits. The cardioprotective effects of several foods and dietary supplements in both animal models and in humans have been explored. It was found that beneficial effects are mainly dependent on antioxidant and anti-inflammatory properties, also involving modulation of mitochondrial function. Resveratrol is one of the most studied phytochemical compounds and it is provided with several benefits in cardiovascular diseases as well as in other pathological conditions (such as cancer). Other relevant compounds are Brassica oleracea, curcumin, and berberine, and they all exert beneficial effects in several diseases. In the attempt to provide a comprehensive reference tool for both researchers and clinicians, we summarized in the present paper the existing literature on both preclinical and clinical cardioprotective effects of each mentioned phytochemical. We structured the discussion of each compound by analyzing, first, its cellular molecular targets of action, subsequently focusing on results from applications in both ex vivo and in vivo models, finally discussing the relevance of the compound in the context of human diseases.