Isoformononetin, a dietary isoflavone protects against streptozotocin induced rat model of neuroinflammation through inhibition of NLRP3/ASC/IL-1 axis activation.

AIMS: Isoformononetin (IFN), a methoxyl isoflavone present in most of human dietary supplements. However, being a highly potent antioxidant and anti-inflammatory molecule, its activity against neuronal oxidative stress and neuroinflammation has not been explored till now. The present study was inquested to assess the antioxidant, anti-apoptotic and anti-inflammatory activity of IFN against streptozotocin induced neuroinflammation in different brain regions of rat. MAIN METHODS: Four groups of animals were subjected to treatment as control, toxic control (STZ; single intracerebrovascular injection), third group (STZ + IFN; 20 mg/kg p.o.), fourth group (IFN) for 14 days. The different brain regions of rats were evaluated for inflammatory, apoptotic and biochemical antioxidant markers. The brain tissues were further assessed for gene expression, immunohistochemical and western blotting examination for localization of inflammasome cascade expression that plays a pivotal role in neuroinflammation. KEY FINDINGS: The modulation in oxidant/antioxidant status after exposure of STZ was significantly balanced after administration of IFN to rats. Further, IFN was also found to be an apoptotic agent as it modulates the apoptotic gene (Bax) and anti-apoptotic gene (BcL2) expression. IFN significantly curtailed the augmented protein expression of NLRP3, NLRP2, ASC, NFκBP65, IL-1ß and caspase-1 due to STZ administration in cortex and hippocampus rat brain regions. SIGNIFICANCE: The aforementioned results proclaim the neuroprotective functioning of IFN against STZ induced inflammation. IFN significantly prevents the neuroinflammation by decreasing the generation of ROS that reduces the activation of NLRP3/ASC/IL-1 axis thereby exerting neuroprotection as evidenced in rat model of STZ induced neuroninflammation.

Piperine and Celecoxib synergistically inhibit colon cancer cell proliferation via modulating Wnt/ß-catenin signaling pathway.

BACKGROUND: Celecoxib (CXB), a selective COX-2 inhibitor NSAID, has exhibited prominent anti-proliferative potential against numerous cancers. However, its low bioavailability and long term exposure related cardiovascular side effects, limit its clinical application. In order to overcome these limitations, natural bioactive compounds with lower toxicity profile are used in combination with therapeutic drugs. Therfore, in this study Piperine (PIP), a natural chemo-preventive agent possessing drug bioavailability enhancing properties, was considered to be used in combination with low doses of CXB. PURPOSE: We hypothesized that the combination of PIP with CXB will have a synergistic anti-proliferative effect on colon cancer cells. STUDY DESIGN: The potency of PIP and CXB alone and in combination was evaluated in HT-29 human colon adenocarcinoma cells and mechanism of growth inhibition was investigated by analyzing the players in apoptotic and Wnt/ß-catenin signaling pathways. METHODS: The effect of PIP on the oral bioavailability of CXB in mice was investigated using HPLC analysis. The study investigated the synergistic anti-proliferative effect of CXB and PIP on HT-29 cells and IEC-6 non-tumorigenic rat intestinal epithelial cells by SRB cell viability assay. Further, the cellular and molecular mechanism(s) involved in the anti-proliferative combinatorial effect was extensively explored in HT-29 cells by flow cytometry and western blotting. The in vivo efficacy of this combination was studied in CT26.WT tumor syngeneic Balb/c mice model. RESULTS: PIP as a bioenhancer increased the oral bioavailability of CXB (129%). The IC50 of CXB and PIP were evaluated to select doses for combination treatment of HT-29 cells. The drug combinations having combination index (CI) less than 1 were screened using CompuSyn software. These combinations were significantly cytotoxic to HT-29 cells but IEC-6 were least effected. Further, the mechanism behind CXB and PIP mediated cell death was explored. The co-treatment led to reactive oxygen species generation, mitochondrial dysfunction, caspase activation and enhanced apoptosis in HT-29 cells. Additionally, the combination treatment synergistically modulated Wnt/ß-catenin pathway, downregulated the stemness markers and boosted therapeutic response in CT26 syngeneic Balb/c mice. CONCLUSION: The outcomes of the study suggests that combining CXB and PIP offers a novel approach for the treatment of colon cancer.

Development and validation of UPLC-MS/MS assay for quantification of cladrin: Absolute bioavailability and dose proportionality study in rats.

Cladrin, an isoflavone is a major bioactive constituent found in stem bark of Butea monosperma with remarkable osteogenic activity. A speedy and sensitive UPLC coupled tandem mass spectrometry (UPLC-MS/MS) method was developed, validated and successfully applied to bioavailability, blood partitioning, plasma protein binding, intravenous and multiple-dose oral pharmacokinetics of cladrin in rats. Separation was done on C18 column (5.0 µm, 4.6 × 50 mm) using mobile phase containing acetonitrile and 0.10% formic acid in the ratio of 65:35 (v/v) with 0.60 mL/min flow rate. The method was highly sensitive and has a short run time of 2.50 min with an excellent linearity (R2 > 0.99) in the range of 0.20-200 µg/L. Absolute bioavailability was found to be 16.58, 19.04 and 6.76% at oral doses of 5, 10, and 20 mg/Kg, respectively. Cladrin was rapidly absorbed (Tmax 3.0 h) with a high apparent volume of distribution (15.03 ±â€¯1.79L/Kg), high clearance (2.27 ±â€¯0.30L/h/Kg) and high plasma protein binding. The present study is a first comprehensive in-vitro as well as the in-vivo preclinical pharmacokinetic report of cladrin giving insights about its drug-likeness and further development as a potential therapeutic agent.

Therapeutic Targeting of NLRP3 Inflammasomes by Natural Products and Pharmaceuticals: A Novel Mechanistic Approach for Inflammatory Diseases.

Inflammasomes are multiprotein complexes having nucleotide-binding domain and leucine-rich repeat consisting members along with pyrin and HIN domain family. An inflammasome mainly consists of cytoplasmic sensor molecule, such as NLRP3, the adaptor apoptosisassociated speck-like protein containing caspase recruitment domain) protein along with effector procaspase-1. The inflammasome regulates caspase-1 activation, resulting in secretion of interleukin- 1ß and interleukin-18. The inflammasome activation is linked with infection, stress, or other immunological signals involved in inflammation. The pathophysiological role of NLRP3 inflammasome in immune regulation, inflammatory receptor-ligand interactions, microbial-associated molecular patterns, danger as well as pathogen associated molecular patterns has been demonstrated in last few years. Furthermore, the role of the inflammasome in peripheral and central nervous system involved with cytokine and chemokine inflammatory responses has been demonstrated in preclinical and clinical studies. The understanding of molecular regulation of inflammasome associated pathways is crucial for drug design and delivery. The use of natural product as an alternate therapy is gaining focus because of easy access and cost effectiveness. A number of herbal extracts and its bioactive constituents known as phytochemicals have shown to be effective in inflammatory response mediated by NLRP3 inflammasomes pathways. To understand the interaction of phytochemicals and inflammasome at the molecular level, it is vital to develop effective drugs that can be evaluated further in the clinical settings. Therefore, this review renders an extensive account of all the phytochemicals which are evaluated either in inflammatory experimental animal models or in immortalized human/animal cell lines that modulate NLRP3 inflammasome mediated pathways to mitigate inflammatory responses with the hope that this pathway modulation by phytochemicals may provide a another class of drugs in the armamentarium as well as novel molecular mechanism of natural products targeting NLRP3 inflammasome.