Vindoline Exhibits Anti-Diabetic Potential in Insulin-Resistant 3T3-L1 Adipocytes and L6 Skeletal Myoblasts.

Type 2 diabetes mellitus (T2DM) emerged as a major health care concern in modern society, primarily due to lifestyle changes and dietary habits. Obesity-induced insulin resistance is considered as the major pathogenic factor in T2DM. In this study, we investigated the effect of vindoline, an indole alkaloid of Catharanthus roseus on insulin resistance (IR), oxidative stress and inflammatory responses in dexamethasone (IR inducer)-induced dysfunctional 3T3-L1 adipocytes and high-glucose-induced insulin-resistant L6-myoblast cells. Results showed that dexamethasone-induced dysfunctional 3T3-L1 adipocytes treated with different concentrations of vindoline significantly enhanced basal glucose consumption, accompanied by increased expression of GLUT-4, IRS-1 and adiponectin. Similarly, vindoline-treated insulin-resistant L6 myoblasts exhibited significantly enhanced glycogen content accompanied with upregulation of IRS-1 and GLUT-4. Thus, in vitro studies of vindoline in insulin resistant skeleton muscle and dysfunctional adipocytes confirmed that vindoline treatment significantly mitigated insulin resistance in myotubes and improved functional status of adipocytes. These results demonstrated that vindoline has the potential to be used as a therapeutic agent to ameliorate obesity-induced T2DM-associated insulin resistance profile in adipocytes and skeletal muscles.

Adenosine receptor activation promotes macrophage class switching from LPS-induced acute inflammatory M1 to anti-inflammatory M2 phenotype.

Lipopolysaccharide induced monocytes/macrophages exhibit a pro-inflammatory M1 phenotype. Elevated levels of the purine nucleoside adenosine play a major role in this response. The role of adenosine receptor modulation in directing the macrophage phenotype switch from proinflammatory classically activated M1 phenotype to an anti-inflammatory alternatively activated M2 phenotype is investigated in this study. The mouse macrophage cell line RAW 264.7 was used as the experimental model and stimulated with Lipopolysaccharide (LPS) at a dose of 1 µg/ml. Adenosine receptors were activated by treating cells with the receptor agonist NECA (1 µM). Adenosine receptor stimulation in macrophages is found to suppress LPS-induced production of proinflammatory mediators (pro-inflammatory cytokines, Reactive Oxygen Species and nitrite levels). M1 marker CD38 (Cluster of Differentiation 38) and CD83 (Cluster of Differentiation 83) were significantly decreased while M2 markers Th2 cytokines, Arginase, TIMP (Tissue Inhibitor of Metalloproteinases) and CD206 (Cluster of Differentiation 206) exhibited an increase. Hence from our study we observed that activation of adenosine receptors can program the macrophages from a pro-inflammatory classically activated M1 phenotype to an anti-inflammatory alternatively activated M2 phenotype. We report the significance and a time course profile of phenotype switching by receptor activation. Adenosine receptor targeting may be explored as a therapeutic intervention strategy in addressing acute inflammation.

Anti-inflammatory Activity of Mollugo cerviana Methanolic Extract in LPS-induced Acute Inflammatory RAW 264.7 Macrophages.

BACKGROUND: The management of acute inflammation, which arises from complex biological responses to harmful stimuli, is an important determinant in the recovery from an otherwise detrimental outcome such as septicemia. However, the side effects and limitations of current therapeutics necessitate the development of newer and safer alternatives. Mollugo cerviana is a common medicinal herb of the Indian subcontinent and has been traditionally used for its fever mitigating anti-microbial and hepatoprotective action. We have already reported the rich presence of radical scavenging phytochemicals in the plant extracts and their strong antioxidant properties. OBJECTIVE: In the present study, we have evaluated the anti-inflammatory effects of methanolic extract (ME) of the areal parts of M. cerviana in a lipopolysaccharide (LPS)-induced acute inflammatory cell culture model. METHODS: RAW 264.7 mouse macrophage cells were stimulated by the bacterial endotoxin LPS at a concentration of 1 µg/mL. Cytotoxicity and anti-inflammatory potential of ME were carried out. RESULTS: The concentration of M. cerviana extract up to 150 µg/ml was found to be non-toxic to cells (MTT and NRU assay). LPS induces acute inflammation by binding to TLR-4 receptors, initiating a downstream signalling cascade that results in pro-inflammatory cytokine secretion. Extract treatment at 100 µg/ml suppressed LPS-induced gene expression (qPCR) and secretion (ELISA) of pro-inflammatory cytokines IL-1ß, IL-6 and TNF-α, and the chemokine CCL2, leading to dampening of the acute inflammatory cascade. LPS-induced elevation of ROS level (DCFDA method) was significantly reduced by extract treatment. Nitric oxide production, as indicated by nitrite level, was significantly reduced post extract treatment. CONCLUSION: This study demonstrated that M. cerviana methanolic extract has a potent antiinflammatory effect in the in vitro acute inflammation model of LPS-stimulated RAW 264.7 cells. There is no reported study so far on the anti-inflammatory properties of M. cerviana in an LPSinduced acute inflammatory model, which closely mimics a human bacteremia response. Hence, this study highlights the therapeutic potential of this extract as a source of anti-inflammatory lead molecules.

Therapeutic Properties of PDMS Nanoparticles: A Promising New Drug Delivery Vehicle against Inflammatory Conditions.

BACKGROUND: Over the last few decades, there has been a stupendous change in the area of drug delivery using particulate delivery systems, with increasing focus on nanoparticles in recent times. Nanoparticles help to improve and alter the pharmacodynamic properties and pharmacokinetics of various types of drug molecules. These features help to protect the drug entity in the systemic circulation, access of the drug to the chosen sites, and to deliver the drug in a controlled and sustained rate at the site of action. OBJECTIVE: Nanoparticle based targeted delivery of anti-inflammatory drugs/signal modulatory agents to the cytoplasm or nuclei of the targeted cell can significantly enhance the precision and efficacy of intended therapeutic activity. To this end, we report ligand free, enhanced intra-nuclear delivery model of anti-inflammatory therapeutics via PDMS nanoparticles. METHODS: PDMS nanoparticles were prepared by sacrificial silica template-based approach and details of their characterization for suitability as a nanoparticle-based delivery material are detailed herein. RESULTS: Biological evaluation for compatibility was carried out and the results showed that the PDMS nanoparticle has no toxicity on RAW 264.7 cells in the concentration range of 10, 20, 40, 60, 80, 100 and 120 µg/mL in culture. Biocompatibility and absence of toxicity were determined by morphological examination and cell viability assays. Drug loading and release kinetics were carried out with the anti-inflammatory drug Diclofenac. CONCLUSION: In this paper, we clearly demonstrate the various aspects of nanoparticle articulation, characterization, effect of their characteristics and their applications as a non-toxic drug delivery molecule for its potential applications in therapeutic delivery of drugs for sustained release.

Anti-inflammatory and anticancer activities of erythrodiol-3-acetate and 2,4-di-tert-butylphenol isolated from Humboldtia unijuga.

Humboldtia unijuga Bedd., endemic to Agasthyamala in Western Ghats in India, is traditionally used by local Kani tribes for chicken pox, head ache and snake bite. This study reports the isolation of erythrodiol-3-acetate (HU-1) and 2,4-di-tert-butylphenol (HU-2) from H. unijuga roots and their anti-inflammatory and anticancer activities in macrophage, skin and breast cancer cell lines. Effects of HU-1 and HU-2 treatments (50, 100 µg/mL) on gene expression profiles of pro-inflammatory cytokines TNFα, IL-6 and IL-1ß, and apoptosis genes p53 and caspase 7 were studied. HU-2 exerted a significantly superior anti-inflammatory effect compared to HU-1 in all three pro-inflammatory genes. HU-2 showed a superior dose dependent anticancer effect through activation of p53 gene over HU-1 in MCF-7 cells. HU-1 exhibited a dose dependent effect on caspase 7 gene in both cell lines while HU-2 was more effective in A431. HU-2 has potential for development as a novel anti-inflammatory and anticancer agent.