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Selective agonism of the estrogen receptor (ER) subtypes, ERα and ERβ, has historically been difficult to achieve due to the high degree of ligand-binding domain structural similarity. Multiple efforts have focused on the use of classical organic scaffolds to model 17β-estradiol geometry in the design of ERβ selective agonists, with several proceeding to various stages of clinical development. Carborane scaffolds offer many unique advantages including the potential for novel ligand/receptor interactions but remain relatively unexplored. We synthesized a series of para-carborane estrogen receptor agonists revealing an ERβ selective structure-activity relationship. We report ERβ agonists with low nanomolar potency, greater than 200-fold selectivity for ERβ over ERα, limited off-target activity against other nuclear receptors, and only sparse CYP450 inhibition at very high micromolar concentrations. The pharmacological properties of our para-carborane ERβ selective agonists measure favorably against clinically developed ERβ agonists and support further evaluation of carborane-based selective estrogen receptor modulators.

Accumulation of senescent cells in tissues with advancing age participates in the pathogenesis of several human age-associated diseases. Specific senescent secretome, the resistance of senescent cells to apoptotic stimuli, and lack of immune system response contribute to the accumulation of senescent cells and their adverse effects in tissues. Inhibition of antiapoptotic machinery, augmented in senescent cells, by BCL-2 protein family inhibitors represents a promising approach to eliminate senescent cells from tissues. This study aimed to explore synergistic and selective senolytic effects of anti-apoptotic BCL-2 family targeting compounds, particularly BH3 mimetics. Using human non-transformed cells RPE-1, BJ, and MRC-5 brought to ionizing radiation-, oncogene-, drug-induced and replicative senescence, we found synergy in combining MCL-1 selective inhibitors with other BH3 mimetics. In an attempt to uncover the mechanism of such synergy, we revealed that the surviving subpopulation of cells resistant to individually applied ABT-737/ABT-263, MIK665, ABT-199, and S63845 BCL-2 family inhibitors showed elevated MCL-1 compared to untreated control cells indicating the presence of a subset of cells expressing high MCL-1 levels and, therefore, resistant to BCL-2 inhibitors within the original population of senescent cells. Overall, we found that combining BCL-2 inhibitors can be beneficial for eliminating senescent cells, thereby enabling use of lower, potentially less toxic, doses of drugs compared to monotherapy, thereby overcoming the resistance of the subpopulation of senescent cells to monotherapy.

Selective agonism of the estrogen receptor (ER) subtypes, ERα and ERβ, has historically been difficult to achieve due to the high degree of ligand-binding domain structural similarity. Multiple efforts have focused on the use of classical organic scaffolds to model 17β-estradiol geometry in the design of ERβ selective agonists, with several proceeding to various stages of clinical development. Carborane scaffolds offer many unique advantages including the potential for novel ligand/receptor interactions but remain relatively unexplored. We synthesized a series of

There is significant number of evidences suggesting the anti-inflammatory properties of gum resin extracts of Boswellia serrata containing 3-O-acetyl-11-keto-β-boswellic acid (AKBA) and their promising potential as therapeutic interventions against inflammatory diseases such as osteoarthritis (OA). Unfortunately, the poor bioavailability of AKBA following oral administration might limit the anti-inflammatory efficacy of standardized Boswellia extract(s). To address this issue, we describe a novel composition called Aflapin, which contains B. serrata extract enriched in AKBA and non-volatile oil portion of B. serrata gum resin. Our observations show that the availability of AKBA in systemic circulation of experimental animals is increased by 51.78% in Aflapin-supplemented animals, in comparison with that of 30% AKBA standardized extract or BE-30 (5-Loxin(®)). Consistently, Aflapin confers better anti-inflammatory efficacy in Freund's Complete Adjuvant (FCA)-induced inflammation model of Sprague-Dawley rats. Interestingly, in comparison with BE-30, Aflapin(®) also provides significantly better protection from IL-1β-induced death of human primary chondrocytes and improves glycosaminoglycans production in human chondrocytes. In Tumor necrosis factor alpha (TNFα)-induced human synovial cells, the inhibitory potential of Aflapin (IC(50) 44.736 ng/ml) on matrix metalloproteinase-3 (MMP-3) production is 14.83% better than that of BE-30 (IC(50) 52.528 ng/ml). In summary, our observations collectively suggest that both the Boswellia products, BE-30 (5-Loxin(®)) and Aflapin, exhibit powerful anti-inflammatory efficacy and anti-arthritic potential. In particular, in comparison with BE-30, Aflapin provides more potential benefits in recovering articular cartilage damage or protection from proteolytic degradation due to inflammatory insult in arthritis such as osteoarthritis or rheumatoid arthritis.

Publisher Summary This chapter describes the components and the applications of toxicogenomics in various fields through nutracetical research, drug development and in reproductive and developmental toxicology. Toxicogenomics is a rapidly developing area that promises to aid scientists in understanding the molecular and cellular effects of toxic agents in biological systems. The components of toxicogenomics are genomic, transcriptom, proteomic, metabolomic and bioinformatic, which are explained here. Mechanistic or investigative research and predictive toxicology are the two broad and overlapping classes of the applications of toxicogenomics. Nutraceutical research has been used for the applications of toxicogenomics, pharmacogenomics, cell biology and clinical investigations addressing the prevention and intervention of diseases. It is anticipated that toxicogenomics will be increasingly integrated into all phases of the drug development process particularly in mechanistic and predictive toxicology, and biomarker discovery. These genomic studies showed the evidence in favor of toxicity potential of DBP in reproductive and developmental biology by altering the expression of genes that are important in sex hormone synthesis and responsible for reproductive organ development. This effort will improve our understanding of conservation of biologic responses to toxic injury and facilitate use of surrogate species that predict the responses in humans. The key goal of toxicogenomic research is to integrate data from multiple sources to produce a comprehensive understanding of the molecular basis of toxicologic responses. Integration of data from different technologies leads to synergistic interpretations beyond what can be resolved when data are analyzed separately or in isolation.