Activation of p300 Histone Acetyltransferase by Small Molecules Altering Enzyme Structure: Probed by Surface-Enhanced Raman Spectroscopy

Flame retardant tetrabromobisphenol A (TBBPA) disrupts histone acetylation during zebrafish maternal-to-zygotic transition

3,3',5.5'-Tetrabromobisphenol A (TBBPA) is a widely used brominated flame-retardant. The objective of this study is to use zebrafish as a model and determine the effects of TBBPA exposure on early embryogenesis. We initiated TBBPA exposures at 0.75 h post fertilization (hpf) and showed that TBBPA induced developmental delays during maternal-to-zygotic transition (MZT) and zygotic genome activation (ZGA). To examine the genetic basis of TBBPA-induced delays, we conducted mRNA-sequencing on embryos exposed to 0 or 40 μM TBBPA from 0.75 hpf to 2, 3.5 or 4.5 hpf. Read count data showed that while TBBPA exposures had no overall impacts on maternal or maternal-zygotic genes, collective read counts for zygotically activated genes were lower in TBBPA treatment at 4.5 hpf compared to time-matched controls, suggesting that TBBPA delays ZGA. Gene ontology assessments for both time- and stage-matched differentially expressed genes revealed TBBPA-induced inhibition of chromatin assembly- a process regulated by histone modifications. Immunostaining and in vitro experiments showed inhibition of histone H3 lysine 27 acetylation (H3K27Ac) as well as its catalyzing enzyme, p300. Finally, co-exposure with a p300 activator showed partial mitigation of effects, demonstrating that inhibition of histone acetylation drives TBBPA-induced developmental delays.

Flame retardant tetrabromobisphenol A (TBBPA) disrupts histone acetylation during zebrafish maternal-to-zygotic transition

3,3',5.5'-Tetrabromobisphenol A (TBBPA) is a widely used brominated flame-retardant utilized in the production of electronic devices and plastic paints. The objective of this study is to use zebrafish as a model and determine the effects of TBBPA exposure on early embryogenesis. We initiated TBBPA exposures (0, 10, 20 and 40μM) at 0.75 h post fertilization (hpf) and monitored early developmental events such as cleavage, blastula and epiboly that encompass maternal-to-zygotic transition (MZT) and zygotic genome activation (ZGA). Our data revealed that TBBPA exposures induced onset of developmental delays by 3 hpf (blastula). By 5.5 hpf (epiboly), TBBPA-exposed (10-20 μM) embryos showed concentration-dependent developmental lag by up to 3 stages or 100% mortality at 40 μM. Embryos exposed to sublethal TBBPA concentrations from 0.75-6 hpf and raised in clean water to 120 hpf showed altered larval photomotor response (LPR), suggesting a compromised developmental health. To examine the genetic basis of TBBPA-induced delays, we conducted mRNA-sequencing on embryos exposed to 0 or 40 μM TBBPA from 0.75 hpf to 2, 3.5 or 4.5 hpf. Read count data showed that while TBBPA exposures had no overall impacts on maternal or maternal-zygotic genes, collective read counts for zygotically activated genes were lower in TBBPA treatment at 4.5 hpf compared to time-matched controls, suggesting that TBBPA delays ZGA. Gene ontology assessments for both time- and stage-matched differentially expressed genes revealed TBBPA-induced inhibition of chromatin assembly- a process regulated by histone modifications. Since acetylation is the primary histone modification system operant during early ZGA, we immunostained embryos with an H3K27Ac antibody and demonstrated reduced acetylation in TBBPA-exposed embryos. Leveraging in silico molecular docking studies and in vitro assays, we also showed that TBBPA potentially binds to P300- a protein that catalyzes acetylation- and inhibits P300 activity. Finally, we co-exposed embryos to 20 μM TBBPA and 50 μM n-(4-chloro-3-trifluoromethyl-phenyl)-2-ethoxy-6-pentadecyl-benzamide (CTPB) -a histone acetyltransferase activator that promotes histone acetylation- and showed that TBBPA-CTPB co or pre-exposures significantly reversed TBBPA-only developmental delays, suggesting that TBBPA-induced phenotypes are indeed driven by repression of histone acetylation. Collectively, our work demonstrates that TBBPA disrupts ZGA and early developmental morphology, potentially by inhibiting histone acetylation. Future studies will focus on mechanisms of TBBPA-induced chromatin modifications.

TIP60 in aging and neurodegeneration

Epigenetic modification of chromatin, including histone methylation and acetylation, plays critical roles in eukaryotic cells and has a significant impact on chromatin structure/accessibility, gene regulation and, susceptibility to aging, neurodegenerative disease, cancer, and other age-related diseases. This article reviews the current advances on TIP60/KAT5, a major histone acetyltransferase with diverse functions in eukaryotes, with emphasis on its regulation of autophagy, proteasome-dependent protein turnover, RNA transcription, DNA repair, circadian rhythms, learning and memory, and other neurological functions implicated in aging and neurodegeneration. Moreover, the promising therapeutic potential of TIP60 is discussed to target Alzheimer's disease and other neurological diseases.

Modeling suggests combined-drug treatments for disorders impairing synaptic plasticity via shared signaling pathways

Genetic disorders such as Rubinstein-Taybi syndrome (RTS) and Coffin-Lowry syndrome (CLS) cause lifelong cognitive disability, including deficits in learning and memory. Can pharmacological therapies be suggested that improve learning and memory in these disorders? To address this question, we simulated drug effects within a computational model describing induction of late long-term potentiation (L-LTP). Biochemical pathways impaired in these and other disorders converge on a common target, histone acetylation by acetyltransferases such as CREB binding protein (CBP), which facilitates gene induction necessary for L-LTP. We focused on four drug classes: tropomyosin receptor kinase B (TrkB) agonists, cAMP phosphodiesterase inhibitors, histone deacetylase inhibitors, and ampakines. Simulations suggested each drug type alone may rescue deficits in L-LTP. A potential disadvantage, however, was the necessity of simulating strong drug effects (high doses), which could produce adverse side effects. Thus, we investigated the effects of six drug pairs among the four classes described above. These combination treatments normalized impaired L-LTP with substantially smaller individual drug 'doses'. In addition three of these combinations, a TrkB agonist paired with an ampakine and a cAMP phosphodiesterase inhibitor paired with a TrkB agonist or an ampakine, exhibited strong synergism in L-LTP rescue. Therefore, we suggest these drug combinations are promising candidates for further empirical studies in animal models of genetic disorders that impair histone acetylation, L-LTP, and learning.

Lysine Acetyltransferase Inhibitors From Natural Sources

Acetylation of histone and non-histone protein lysine residues has been widely described as a critical modulator of several cell functions in humans. Lysine acetyltransferases (KATs) catalyse the transfer of acetyl groups on substrate proteins and are involved in multiple physiological processes such as cell signalling, metabolism, gene regulation, and apoptosis. Given the pivotal role of acetylation, the alteration of KATs enzymatic activity has been clearly linked to various cellular dysfunctions leading to several inflammatory, metabolic, neurological, and cancer diseases. Hence, the use KAT inhibitors (KATi) has been suggested as a potentially successful strategy to reverse or prevent these conditions. To date, only a few KATi have proven to be potential drug candidates, and there is still a keen interest in designing molecules showing drug-like properties from both pharmacodynamics and pharmacokinetics point of view. Increasing literature evidence has been highlighting natural compounds as a wide source of molecular scaffolds for developing therapeutic agents, including KATi. In fact, several polyphenols, catechins, quinones, and peptides obtained from natural sources (including nuts, oils, root extracts, and fungi metabolites) have been described as promising KATi. Here we summarize the features of this class of compounds, describing their modes of action, structure-activity relationships and (semi)-synthetic derivatives, with the aim of assisting the development of novel more potent, isoform selective and drug-like KATi.

Chromatin-Remodeled State in Lymphoma

PURPOSE OF REVIEW

Emerging evidence has shown that epigenetic derangements might drive and promote tumorigenesis in various types of malignancies and is prevalent in both B cell and T cell lymphomas. The purpose of this review is to explain how the epigenetic derangements result in a chromatin-remodeled state in lymphoma and contribute to the biology and clinical features of these tumors.

RECENT FINDINGS

Studies have explored on the functional role of epigenetic derangements in chromatin remodeling and lymphomagenesis. For example, the haploinsufficiency of CREBBP facilitates malignant transformation in mice and directly implicates the importance to re-establish the physiologic acetylation level. New findings identified 4 prominent DLBCL subtypes, including EZB-GC-DLBCL subtype that enriched in mutations of CREBBP, EP300, KMT2D, and SWI/SNF complex genes. EZB subtype has a worse prognosis than other GCB-tumors. Moreover, the action of the histone modifiers as well as chromatin-remodeling factors (e.g., SWI/SNF complex) cooperates to influence the chromatin state resulting in transcription repression. Drugs that alter the epigenetic landscape have been approved in T cell lymphoma. In line with this finding, epigenetic lesions in histone modifiers have recently been uncovered in this disease, further confirming the vulnerability to the therapies targeting epigenetic derangements. Modulating the chromatin state by epigenetic-modifying agents provides precision-medicine opportunities to patients with lymphomas that depend on this biology.

Epigenetic Mechanisms Underlying Organic Solute Transporter β Repression in Colorectal Cancer

Colorectal cancer (CRC) is known to be the third most common cancer disease and the fourth-leading cause of cancer-related deaths worldwide. Bile acid, especially deoxycholic acid and lithocholic acid, were revealed to play an important role during carcinogenesis of CRC. In this study, we found organic solute transporter β (OSTβ), an important subunit of a bile acid export transporter OSTα-OSTβ, was noticeably downregulated in CRC. The decline of OSTβ expression in CRC was determined by Western blot and real-time polymerase chain reaction (RT-PCR), whereas chromatin immunoprecipitation (ChIP) was used to evaluate the histone acetylation state at the OSTβ promoter region in vivo and in vitro. CRC cell lines HT29 and HCT15 were treated with trichostation A (TSA) for the subsequent determination, including RT-PCR, small interfering RNA (siRNA) knockdown, ChIP, and dual-luciferase reporter gene assay, to find out which histone acetyltransferases and deacetylases exactly participated in regulation. We demonstrated that after TSA treatment, OSTβ expression increased noticeably because of upregulated H3K27Ac state at OSTβ promoter region. We found that stimulating the expression of p300 with CTB (Cholera Toxin B subunit, an activator of p300) and inhibiting p300 expression with C646 (an inhibitor of p300) or siRNA designed for p300 could control OSTβ expression through modulating H3K27Ac state at OSTβ promoter region. Therefore, downregulated expression of p300 in CRC may cause low expression of OSTβ in CRC via epigenetic regulation. Generally, we revealed a novel epigenetic mechanism underlying OSTβ repression in CRC, hoping this mechanism would help us to understand and inhibit carcinogenesis of CRC. SIGNIFICANCE STATEMENT: Organic solute transporter β (OSTβ) expression is lower in colon cancer tissues compared with adjacent normal tissues. We revealed the epigenetic mechanisms of it and proved that p300 controls OSTβ expression through modulating H3K27Ac state at OSTβ promoter region and hence causes low expression of OSTβ in colorectal cancer.

Promoting tau secretion and propagation by hyperactive p300/CBP via autophagy-lysosomal pathway in tauopathy

BACKGROUND

The trans-neuronal propagation of tau has been implicated in the progression of tau-mediated neurodegeneration. There is critical knowledge gap in understanding how tau is released and transmitted, and how that is dysregulated in diseases. Previously, we reported that lysine acetyltransferase p300/CBP acetylates tau and regulates its degradation and toxicity. However, whether p300/CBP is involved in regulation of tau secretion and propagation is unknown.

METHOD

We investigated the relationship between p300/CBP activity, the autophagy-lysosomal pathway (ALP) and tau secretion in mouse models of tauopathy and in cultured rodent and human neurons. Through a high-through-put compound screen, we identified a new p300 inhibitor that promotes autophagic flux and reduces tau secretion. Using fibril-induced tau spreading models in vitro and in vivo, we examined how p300/CBP regulates tau propagation.

RESULTS

Increased p300/CBP activity was associated with aberrant accumulation of ALP markers in a tau transgenic mouse model. p300/CBP hyperactivation blocked autophagic flux and increased tau secretion in neurons. Conversely, inhibiting p300/CBP promoted autophagic flux, reduced tau secretion, and reduced tau propagation in fibril-induced tau spreading models in vitro and in vivo.

CONCLUSIONS

We report that p300/CBP, a lysine acetyltransferase aberrantly activated in tauopathies, causes impairment in ALP, leading to excess tau secretion. This effect, together with increased intracellular tau accumulation, contributes to enhanced spreading of tau. Our findings suggest that inhibition of p300/CBP as a novel approach to correct ALP dysfunction and block disease progression in tauopathy.

Defective Base Excision Repair of Oxidative DNA Damage in Vascular Smooth Muscle Cells Promotes Atherosclerosis

Supplemental Digital Content is available in the text.

Background:

Atherosclerotic plaques demonstrate extensive accumulation of oxidative DNA damage, predominantly as 8-oxoguanine (8oxoG) lesions. 8oxoG is repaired by base excision repair enzymes; however, the mechanisms regulating 8oxoG accumulation in vascular smooth muscle cells (VSMCs) and its effects on their function and in atherosclerosis are unknown.

Methods:

We studied levels of 8oxoG and its regulatory enzymes in human atherosclerosis, the mechanisms regulating 8oxoG repair and the base excision repair enzyme 8oxoG DNA glycosylase I (OGG1) in VSMCs in vitro, and the effects of reducing 8oxoG in VSMCs in atherosclerosis in ApoE^−/− mice.

Results:

Human plaque VSMCs showed defective nuclear 8oxoG repair, associated with reduced acetylation of OGG1. OGG1 was a key regulatory enzyme of 8oxoG repair in VSMCs, and its acetylation was crucial to its repair function through regulation of protein stability and expression. p300 and sirtuin 1 were identified as the OGG1 acetyltransferase and deacetylase regulators, respectively, and both proteins interacted with OGG1 and regulated OGG1 acetylation at endogenous levels. However, p300 levels were decreased in human plaque VSMCs and in response to oxidative stress, suggesting that reactive oxygen species–induced regulation of OGG1 acetylation could be caused by reactive oxygen species–induced decrease in p300 expression. We generated mice that express VSMC-restricted OGG1 or an acetylation defective version (SM22α-OGG1 and SM22α-OGG1^K-R mice) and crossed them with ApoE^−/− mice. We also studied ApoE^−/− mice deficient in OGG1 (OGG1^−/−). OGG1^−/− mice showed increased 8oxoG in vivo and increased atherosclerosis, whereas mice expressing VSMC-specific OGG1 but not the acetylation mutant OGG1^K-R showed markedly reduced intracellular 8oxoG and reduced atherosclerosis. VSMC OGG1 reduced telomere 8oxoG accumulation, DNA strand breaks, cell death and senescence after oxidant stress, and activation of proinflammatory pathways.

Conclusions:

We identify defective 8oxoG base excision repair in human atherosclerotic plaque VSMCs, OGG1 as a major 8oxoG repair enzyme in VSMCs, and p300/sirtuin 1 as major regulators of OGG1 through acetylation/deacetylation. Reducing oxidative damage by rescuing OGG1 activity reduces plaque development, indicating the detrimental effects of 8oxoG on VSMC function.

Discordant Effects of Putative Lysine Acetyltransferase Inhibitors in Biochemical and Living Systems

Lysine acetyltransferases (KATs) are exquisitely fine-tuned to target specific lysine residues on many proteins, including histones, with aberrant acetylation at distinct lysines implicated in different pathologies. However, researchers face a lack of molecular tools to probe the importance of site-specific acetylation events in vivo. Because of this, there can be a disconnect between the predicted in silico or in vitro effects of a drug and the actual observable in vivo response. We have previously reported on how an in vitro biochemical analysis of the site-specific effects of the compound C646 in combination with the KAT p300 can accurately predict changes in histone acetylation induced by the same compound in cells. Here, we build on this effort by further analyzing a number of reported p300 modulators, while also extending the analysis to correlate the effects of these drugs to developmental and phenotypical changes, utilizing cellular and zebrafish model systems. While this study demonstrates the utility of biochemical models as a starting point for predicting in vivo activity of multi-site targeting KATs, it also highlights the need for the development of new enzyme inhibitors that are more specific to the regulation of KAT activity in vivo.

Histone acetyltransferase inhibitors: An overview in synthesis, structure-activity relationship and molecular mechanism

Acetylation, a key component in post-translational modification regulated by HATs and HDACs, is relevant to many crucial cellular contexts in organisms. Based on crucial pharmacophore patterns and the structure of targeted proteins, HAT inhibitors are designed and modified for higher affinity and better bioactivity. However, there are still some challenges, such as cell permeability, selectivity, toxicity and synthetic availability, which limit the improvement of HAT inhibitors. So far, only few HAT inhibitors have been approved for commercialization, indicating the urgent need for more successful and effective structure-based drug design and synthetic strategies. Here, we summarized three classes of HAT inhibitors based on their sources and structural scaffolds, emphasizing on their synthetic methods and structure-activity relationships and molecular mechanisms, hoping to facilitate the development and further application of HAT inhibitors.

Investigation of activation mechanism and conformational stability of N-(4-chloro-3-trifluoromethyl-phenyl)-2-ethoxybenzamide and N-(4-chloro-3-trifluoromethyl-phenyl)-2-ethoxy-6-pentadecyl-benzamide in the: active site of p300 histone acetyl transferase enzyme by molecular dynamics and binding free energy studies

The CBP (CREB-binding protein) and p300 are related to transcriptional coactivator family and are involved in several post-translational modifications, in which the acetylation is an important factor because it commences the transcription process. Experimental studies report that CTPB (N-(4-chloro-3-trifluoromethyl-phenyl)-2-ethoxy-6-pentadecyl-benzamide) and CTB (N-(4-chloro-3-trifluoromethyl-phenyl)-2-ethoxybenzamide) are good activators of p300 HAT enzyme, but yet, the molecular mechanism of their activation is not explored. The present study pertains to determine the intermolecular interactions, stability and binding free energy of CTB and CTPB from the molecular docking, molecular dynamics (MD) simulation and binding free energy calculation. The docking studies of the molecules reveal that the docking score of CTPB (-15.64 kcal/mol) is higher than that of CTB (-12.30 kcal/mol); on the contrary, CTB forms a strong interaction with the key residues of catalytic site (Tyr1467 and Trp1436) compared with CTPB. The MD simulation shows the stability of both molecules in the active site of p300 and their interactions. Furthermore, both docking and MD simulation studies of CTB confirm that it forms expected key interactions and retain the interactions with the active site amino acid residues of p300 when compared with CTPB. For this reason, the CTB recruits more acetyl-CoA in the active site of p300 compared with CTPB; it leads to activate the acetylation process; hence, CTB may be a best activator than CTPB. The binding free energy value of CTPB (-24.79  ±  2.38 kcal/mol) is higher when compared with that of CTB (-12.14  ±  1.30 kcal/mol) molecule; perhaps, the interaction of pentadecyl chain of CTPB with p300, whereas in CTB, such a group is absent. Communicated by Ramaswamy H. Sarma.

Mutant and Wild-Type Tumor Suppressor p53 Induces p300 Autoacetylation

The transcriptional co-activator p300 is essential for p53 transactivation, although its precise role remains unclear. We report that p53 activates the acetyltransferase activity of p300 through the enhancement of p300 autoacetylation. Autoacetylated p300 accumulates near the transcription start sites accompanied by a similar enrichment of activating histone marks near those sites. Abrogation of p53-p300 interaction by a site-directed peptide inhibitor abolished p300-mediated histone acetylation, suggesting a crucial role played by the activation in p53-mediated gene regulation. Gain-of-function mutant p53, known to impart aggressive proliferative properties in tumor cells, also activates p300 autoacetylation. The same peptide abolished many of the gain-of-function properties of mutant p53 as well. Reversal of gain-of-function properties of mutant p53 suggests that molecules targeting the p53-p300 interface may be good candidates for anti-tumor drugs.

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Wild-type and mutant p53 are potent inducers of p300 autoacetylation

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p53 activates p300 catalytic activity by altering its structural conformation

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Induction of p300 autoacetylation possibly enhances p53-targeted gene expression

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Mutant-p53-induced p300 autoacetylation could be critical for tumorigenicity

Epigenetic modulation by small molecule compounds for neurodegenerative disorders

The accumulation of somatic and genetic mutations which altered the structure and coding information of the DNA are the major cause of neurological disorders. However, our recent understanding of molecular mechanisms of 'epigenetic' phenomenon reveals that the modifications of chromatin play a significant role in the development and severity of neurological disorders. These epigenetic processes are dynamic and reversible as compared to genetic ablations which are stable and irreversible. Therefore, targeting these epigenetic processes through small molecule modulators are of great therapeutic potential. To date, large number of small molecule modulators have been discovered which are capable of altering the brain pathology by targeting epigenetic enzymes. In this review, we shall put forward the key studies supporting the role of altered epigenetic processes in neurological disorders with especial emphasis on neurodegenerative disorders. A few small molecule modulators which have been shown to possess promising results in the animal model system of neurological disorders will also be discussed with future perspectives.

Class III PI3K Positively Regulates Platelet Activation and Thrombosis via PI(3)P-Directed Function of NADPH Oxidase

OBJECTIVE

Class III phosphoinositide 3-kinase, also known as VPS34 (vacuolar protein sorting 34), is a highly conserved enzyme regulating important cellular functions such as NADPH oxidase (NOX) assembly, membrane trafficking, and autophagy. Although VPS34 is expressed in platelets, its involvement in platelet activation remains unclear. Herein, we investigated the role of VPS34 in platelet activation and thrombus formation using VPS34 knockout mice.

APPROACH AND RESULTS

Platelet-specific VPS34-deficient mice were generated and characterized. VPS34 deficiency in platelets did not influence tail bleeding time. In a ferric chloride-induced mesenteric arteriolar thrombosis model, VPS34^-/- mice exhibited a prolonged vessel occlusion time compared with wild-type mice (42.05±4.09 versus 18.30±2.47 minutes). In an in vitro microfluidic whole-blood perfusion assay, thrombus formation on collagen under arterial shear was significantly reduced for VPS34^-/- platelets. VPS34^-/- platelets displayed an impaired aggregation and dense granule secretion in response to low doses of collagen or thrombin. VPS34 deficiency delayed clot retraction but did not influence platelet spreading on fibrinogen. We also demonstrated that VPS34 deficiency altered the basal level of autophagy in resting platelets and hampered NOX assembly and mTOR (mammalian target of rapamycin) signaling during platelet activation. Importantly, we identified the NOX-dependent reactive oxygen species generation as the major downstream effector of VPS34, which in turn can mediate platelet activation. In addition, by using a specific inhibitor 3-methyladenine, VPS34 was found to operate through a similar NOX-dependent mechanism to promote human platelet activation.

CONCLUSIONS

Platelet VPS34 is critical for thrombosis but dispensable for hemostasis. VPS34 regulates platelet activation by influencing NOX assembly.

Valproic acid exposure decreases Cbp/p300 protein expression and histone acetyltransferase activity in P19 cells

The teratogenicity of the antiepileptic drug valproic acid (VPA) is well established and its inhibition of histone deacetylases (HDAC) is proposed as an initiating factor. Recently, VPA-mediated HDAC inhibition was demonstrated to involve transcriptional downregulation of histone acetyltransferases (HATs), which was proposed to compensate for the increased acetylation resulting from HDAC inhibition. Cbp and p300 are HATs required for embryonic development and deficiencies in either are associated with congenital malformations and embryolethality. The objective of the present study was to characterize Cbp/p300 following VPA exposure in P19 cells. Consistent with previous studies, exposure to 5mM VPA over 24h induced a moderate decrease in Cbp/p300 mRNA, which preceded a strong decrease in total cellular protein mediated by ubiquitin-proteasome degradation. Nuclear Cbp/p300 protein was also decreased following VPA exposure, although to a lesser extent. Total cellular and nuclear p300 HAT activity was reduced proportionately to p300 protein levels, however while total cellular HAT activity also decreased, nuclear HAT activity was unaffected. Using the Cbp/p300 HAT inhibitor C646, we demonstrated that HAT inhibition similarly affected many of the same endpoints as VPA, including increased reactive oxygen species and caspase-3 cleavage, the latter of which could be attenuated by pre-treatment with the antioxidant catalase. C646 exposure also decreased NF-κB/p65 protein, which was not due to reduced mRNA and was not attenuated with catalase pre-treatment. This study provides support for an adaptive HAT response following VPA exposure and suggests that reduced Cbp/p300 HAT activity could contribute to VPA-mediated alterations.

Modulation of p300/CBP Acetylation of Nucleosomes by Bromodomain Ligand I-CBP112

The histone acetyltransferase (HAT) enzymes p300 and CBP are closely related paralogs that serve as transcriptional coactivators and have been found to be dysregulated in cancer and other diseases. p300/CBP is a multidomain protein and possesses a highly conserved bromodomain that has been shown to bind acetylated Lys residues in both proteins and various small molecules, including I-CBP112 and CBP30. Here we show that the ligand I-CBP112 can stimulate nucleosome acetylation up to 3-fold while CBP30 does not. Activation of p300/CBP by I-CBP112 is not observed with the isolated histone H3 substrate but requires a nucleosome substrate. I-CBP112 does not impact nucleosome acetylation by the isolated p300 HAT domain, and the effects of I-CBP112 on p300/CBP can be neutralized by CBP30, suggesting that I-CBP112 likely allosterically activates p300/CBP through bromodomain interactions. Using mass spectrometry and Western blots, we have found that I-CBP112 particularly stimulates acetylation of Lys18 of histone H3 (H3K18) in nucleosomes, an established in vivo site of p300/CBP. In addition, we show that I-CBP112 enhances H3K18 acetylation in acute leukemia and prostate cancer cells in a concentration range commensurate with its antiproliferative effects. Our findings extend the known pharmacology of bromodomain ligands in the regulation of p300/CBP and suggest a novel approach to modulating histone acetylation in cancer.

Analysis of TRRAP as a Potential Molecular Marker and Therapeutic Target for Breast Cancer

PURPOSE

This study was designed to assess the protein levels of transformation/transcription domain-associated protein (TRRAP) in invasive ductal breast carcinomas, and investigated the association between TRRAP and the clinicopathological features of breast cancer.

METHODS

We examined TRRAP protein expression in 470 breast cancer tissues and normal breast tissues by tissue microarray to study the correlation between TRRAP expression and clinicopathological features. This was analyzed using the chi-square test. Kaplan-Meier survival curves and log-rank tests were applied to analyze the survival status. Cox regression was applied for multivariate analysis of prognosis.

RESULTS

The data demonstrated that expression of TRRAP was significantly lower in breast carcinomas (36.6%) than in corresponding normal breast tissues (50.8%). In addition, TRRAP protein levels negatively correlated with tumor size, and indicated poor differentiation, increased nodal involvement, and low p53-positive rates. Analysis of survival revealed that lower TRRAP expression correlated with shorter survival time. Univariate analyses identified TRRAP and progesterone receptor as independent protective factors for breast cancer prognosis. However, Ki-67, tumor size, and nodal involvement appeared to be independent risk factors.

CONCLUSION

The findings indicate a significant correlation between TRRAP protein levels and adverse prognosis in breast cancer. Therefore, TRRAP could be a prognostic biomarker for breast cancer. In addition, TRRAP is also a predictive biomarker of breast cancer treatment.

Aberrant lysine acetylation in tumorigenesis: Implications in the development of therapeutics

The 'language' of covalent histone modifications translates environmental and cellular cues into gene expression. This vast array of post-translational modifications on histones are more than just covalent moieties added onto a protein, as they also form a platform on which crucial cellular signals are relayed. The reversible lysine acetylation has emerged as an important post-translational modification of both histone and non-histone proteins, dictating numerous epigenetic programs within a cell. Thus, understanding the complex biology of lysine acetylation and its regulators is essential for the development of epigenetic therapeutics. In this review, we will attempt to address the complexities of lysine acetylation in the context of tumorigenesis, their role in cancer progression and emphasize on the modalities developed to target lysine acetyltransferases towards cancer treatment.

Reproducible and label-free biosensor for the selective extraction and rapid detection of proteins in biological fluids

Erythropoietin (EPO), a glycoprotein hormone of ∼34 kDa, is an important hematopoietic growth factor, mainly produced in the kidney and controls the number of red blood cells circulating in the blood stream. Sensitive and rapid recombinant human EPO (rHuEPO) detection tools that improve on the current laborious EPO detection techniques are in high demand for both clinical and sports industry. A sensitive aptamer-functionalized biosensor (aptasensor) has been developed by controlled growth of gold nanostructures (AuNS) over a gold substrate (pAu/AuNS). The aptasensor selectively binds to rHuEPO and, therefore, was used to extract and detect the drug from horse plasma by surface enhanced Raman spectroscopy (SERS). Due to the nanogap separation between the nanostructures, the high population and distribution of hot spots on the pAu/AuNS substrate surface, strong signal enhancement was acquired. By using wide area illumination (WAI) setting for the Raman detection, a low RSD of 4.92% over 150 SERS measurements was achieved. The significant reproducibility of the new biosensor addresses the serious problem of SERS signal inconsistency that hampers the use of the technique in the field. The WAI setting is compatible with handheld Raman devices. Therefore, the new aptasensor can be used for the selective extraction of rHuEPO from biological fluids and subsequently screened with handheld Raman spectrometer for SERS based in-field protein detection.

A Synthetic DNA-Binding Domain Guides Distinct Chromatin-Modifying Small Molecules to Activate an Identical Gene Network

Synthetic dual-function ligands targeting specific DNA sequences and histone-modifying enzymes were applied to achieve regulatory control over multi-gene networks in living cells. Unlike the broad array of targeting small molecules for histone deacetylases (HDACs), few modulators are known for histone acetyltransferases (HATs), which play a central role in transcriptional control. As a novel chemical approach to induce selective HAT-regulated genes, we conjugated a DNA-binding domain (DBD) "I" to N-(4-chloro-3-trifluoromethyl-phenyl)-2-ethoxy-benzamide (CTB), an artificial HAT activator. In vitro enzyme activity assays and microarray studies were used to demonstrate that distinct functional small molecules could be transformed to have identical bioactivity when conjugated with a targeting DBD. This proof-of-concept synthetic strategy validates the switchable functions of HDACs and HATs in gene regulation and provides a molecular basis for developing versatile bioactive ligands.

Potential biological applications of bio-based anacardic acids and their derivatives

Cashew nut shells (CNS), which are agro wastes from cashew nut processing factories, have proven to be among the most versatile bio-based renewable materials in the search for functional materials and chemicals from renewable resources. CNS are produced in the cashew nut processing process as waste, but they contain cashew nut shell liquid (CNSL) up to about 30-35 wt. % of the nut shell weight depending on the method of extraction. CNSL is a mixture of anacardic acid, cardanol, cardol, and methyl cardol, and the structures of these phenols offer opportunities for the development of diverse products. For anacardic acid, the combination of phenolic, carboxylic, and a 15-carbon alkyl side chain functional group makes it attractive in biological applications or as a synthon for the synthesis of a multitude of bioactive compounds. Anacardic acid, which is about 65% of a CNSL mixture, can be extracted from the agro waste. This shows that CNS waste can be used to extract useful chemicals and thus provide alternative green sources of chemicals, apart from relying only on the otherwise declining petroleum based sources. This paper reviews the potential of anacardic acids and their semi-synthetic derivatives for antibacterial, antitumor, and antioxidant activities. The review focuses on natural anacardic acids from CNS and other plants and their semi-synthetic derivatives as possible lead compounds in medicine. In addition, the use of anacardic acid as a starting material for the synthesis of various biologically active compounds and complexes is reported.

Integrating epigenetic modulators into NanoScript for enhanced chondrogenesis of stem cells

N-(4-Chloro-3-(trifluoromethyl)phenyl)-2-ethoxybenzamide (CTB) is a small molecule that functions by altering the chromatin architecture to modulate gene expression. We report a new CTB derivative with increased solubility and demonstrate CTB's functionality by conjugating it on the recently established NanoScript platform to enhance gene expression and induce stem cell differentiation. NanoScript is a nanoparticle-based artificial transcription factor that emulates the structure and function of transcription factor proteins (TFs) to effectively regulate endogenous gene expression. Modifying NanoScript with CTB will more closely replicate the TF structure and enhance CTB functionality and gene expression. To this end, we first conjugated CTB onto NanoScript and initiated a time-dependent increase in histone acetyltransferase activity. Next, because CTB is known to trigger the pathway involved in regulating Sox9, a master regulator of chondrogenic differentiation, we modifed a Sox9-specific NanoScript with CTB to enhance chondrogenic gene activity and differentiation. Because NanoScript is a tunable and robust platform, it has potential for various gene-regulating applications, such as stem cell differentiation.

Changing the selectivity of p300 by acetyl-CoA modulation of histone acetylation

Determining how histone acetylation is regulated is vital for treating the many diseases associated with its misregulation, including heart disease, neurological disorders, and cancer. We have previously reported that acetyl-CoA levels alter p300 histone acetylation in a site-specific manner in vitro. Here, we further investigate how changing acetyl-CoA concentrations alter the histone acetylation pattern by altering p300 specificity. Interestingly, these changes are not a simple global change in acetylation, but rather site specific changes, whereby acetylation at some sites increase while others decrease. We also demonstrate how the p300 inhibitor C646 can pharmacologically alter p300 histone acetylation patterns in vitro and in cells. This study provides insight into the mechanisms regulating p300 residue specificity, a potential means for altering p300 dependent histone acetylation, and an investigation into altering histone acetylation patterns in cells.

Simulations suggest pharmacological methods for rescuing long-term potentiation

Congenital cognitive dysfunctions are frequently due to deficits in molecular pathways that underlie the induction or maintenance of synaptic plasticity. For example, Rubinstein-Taybi syndrome (RTS) is due to a mutation in cbp, encoding the histone acetyltransferase CREB-binding protein (CBP). CBP is a transcriptional co-activator for CREB, and induction of CREB-dependent transcription plays a key role in long-term memory (LTM). In animal models of RTS, mutations of cbp impair LTM and late-phase long-term potentiation (LTP). As a step toward exploring plausible intervention strategies to rescue the deficits in LTP, we extended our previous model of LTP induction to describe histone acetylation and simulated LTP impairment due to cbp mutation. Plausible drug effects were simulated by model parameter changes, and many increased LTP. However no parameter variation consistent with a effect of a known drug class fully restored LTP. Thus we examined paired parameter variations consistent with effects of known drugs. A pair that simulated the effects of a phosphodiesterase inhibitor (slowing cAMP degradation) concurrent with a deacetylase inhibitor (prolonging histone acetylation) restored normal LTP. Importantly these paired parameter changes did not alter basal synaptic weight. A pair that simulated the effects of a phosphodiesterase inhibitor and an acetyltransferase activator was similarly effective. For both pairs strong additive synergism was present. The effect of the combination was greater than the summed effect of the separate parameter changes. These results suggest that promoting histone acetylation while simultaneously slowing the degradation of cAMP may constitute a promising strategy for restoring deficits in LTP that may be associated with learning deficits in RTS. More generally these results illustrate how the strategy of combining modeling and empirical studies may provide insights into the design of effective therapies for improving long-term synaptic plasticity and learning associated with cognitive disorders.

SERS and MD simulation studies of a kinase inhibitor demonstrate the emergence of a potential drug discovery tool

We demonstrate the use of surface-enhanced Raman spectroscopy (SERS) as an excellent tool for identifying the binding site of small molecules on a therapeutically important protein. As an example, we show the specific binding of the common antihypertension drug felodipine to the oncogenic Aurora A kinase protein via hydrogen bonding interactions with Tyr-212 residue to specifically inhibit its activity. Based on SERS studies, molecular docking, molecular dynamics simulation, biochemical assays, and point mutation-based validation, we demonstrate the surface-binding mode of this molecule in two similar hydrophobic pockets in the Aurora A kinase. These binding pockets comprise the same unique hydrophobic patches that may aid in distinguishing human Aurora A versus human Aurora B kinase in vivo. The application of SERS to identify the specific interactions between small molecules and therapeutically important proteins by differentiating competitive and noncompetitive inhibition demonstrates its ability as a complementary technique. We also present felodipine as a specific inhibitor for oncogenic Aurora A kinase. Felodipine retards the rate of tumor progression in a xenografted nude mice model. This study reveals a potential surface pocket that may be useful for developing small molecules by selectively targeting the Aurora family kinases.

Allosteric transition induced by Mg²⁺ ion in a transactivator monitored by SERS

We demonstrate the utility of the surface-enhanced Raman spectroscopy (SERS) to monitor conformational transitions in protein upon ligand binding. The changes in protein's secondary and tertiary structures were monitored using amide and aliphatic/aromatic side chain vibrations. Changes in these bands are suggestive of the stabilization of the secondary and tertiary structure of transcription activator protein C in the presence of Mg(2+) ion, whereas the spectral fingerprint remained unaltered in the case of a mutant protein, defective in Mg(2+) binding. The importance of the acidic residues in Mg(2+) binding, which triggers an overall allosteric transition in the protein, is visualized in the molecular model. The present study thus opens up avenues toward the application of SERS as a potential tool for gaining structural insights into the changes occurring during conformational transitions in proteins.

Naphthoquinone-mediated inhibition of lysine acetyltransferase KAT3B/p300, basis for non-toxic inhibitor synthesis

Hydroxynaphthoquinone-based inhibitors of the lysine acetyltransferase KAT3B (p300), such as plumbagin, are relatively toxic. Here, we report that free thiol reactivity and redox cycling properties greatly contribute to the toxicity of plumbagin. A reactive 3rd position in the naphthoquinone derivatives is essential for thiol reactivity and enhances redox cycling. Using this clue, we synthesized PTK1, harboring a methyl substitution at the 3rd position of plumbagin. This molecule loses its thiol reactivity completely and its redox cycling ability to a lesser extent. Mechanistically, non-competitive, reversible binding of the inhibitor to the lysine acetyltransferase (KAT) domain of p300 is largely responsible for the acetyltransferase inhibition. Remarkably, the modified inhibitor PTK1 was a nearly non-toxic inhibitor of p300. The present report elucidates the mechanism of acetyltransferase activity inhibition by 1,4-naphthoquinones, which involves redox cycling and nucleophilic adduct formation, and it suggests possible routes of synthesis of the non-toxic inhibitor.

Acetyltransferases (HATs) as targets for neurological therapeutics

The acetylation of histone and non-histone proteins controls a great deal of cellular functions, thereby affecting the entire organism, including the brain. Acetylation modifications are mediated through histone acetyltransferases (HAT) and deacetylases (HDAC), and the balance of these enzymes regulates neuronal homeostasis, maintaining the pre-existing acetyl marks responsible for the global chromatin structure, as well as regulating specific dynamic acetyl marks that respond to changes and facilitate neurons to encode and strengthen long-term events in the brain circuitry (e.g., memory formation). Unfortunately, the dysfunction of these finely-tuned regulations might lead to pathological conditions, and the deregulation of the HAT/HDAC balance has been implicated in neurological disorders. During the last decade, research has focused on HDAC inhibitors that induce a histone hyperacetylated state to compensate acetylation deficits. The use of these inhibitors as a therapeutic option was efficient in several animal models of neurological disorders. The elaboration of new cell-permeant HAT activators opens a new era of research on acetylation regulation. Although pathological animal models have not been tested yet, HAT activator molecules have already proven to be beneficial in ameliorating brain functions associated with learning and memory, and adult neurogenesis in wild-type animals. Thus, HAT activator molecules contribute to an exciting area of research.

Analysis of protein acetyltransferase structure-function relation by surface-enhanced raman scattering (SERS): a tool to screen and characterize small molecule modulators

Among the different posttranslational modifications (PTMs) that significantly regulate the protein function, lysine acetylation has become the major focus, especially to understand the epigenetic role of the acetyltransferases, in cellular physiology. Furthermore, dysfunction of these acetyltransferases is well documented under pathophysiological conditions. Therefore, it is important to understand the dynamic structure-function relationship of acetyltransferases in a relatively less complicated and faster method, which could be efficiently exploited to design and synthesis of small molecule modulators (activators/inhibitors) of these enzymes for in vivo functional analysis and therapeutic purposes. We have developed surface-enhanced Raman scattering (SERS) method, for acetyltransferases towards this goal. By employing SERS, we have not only demonstrated the autoacetylation induced structural changes of p300 enzyme but also could use this technique to characterize and design potent, specific inhibitors as well as activators of the p300. In this chapter we shall describe the methods in detail which could be highly useful for other classes of HATs and PTM enzymes.

Charge density distribution and the electrostatic moments of CTPB in the active site of p300 enzyme: a DFT and charge density study

A molecular docking and charge density analysis have been carried out to understand the conformational change, charge distribution and electrostatic properties of N-(4-chloro-3-trifluoromethyl-phenyl)-2-ethoxy-6-pentadecyl-benzamide (CTPB) in the active site of p300. The nearest neighbors, shortest intermolecular contacts between CTPB-p300 and the lowest binding energy of CTPB have been analyzed from the docking analysis. Further, a charge density analysis has been carried out for the molecule in gas phase and for the corresponding molecule lifted from the active site of p300. Due to the intermolecular interaction between CTPB and the amino acids of active site, the conformation of the CTPB has been significantly altered (particularly the pentadecyl chain). CTPB forms strong interaction with the amino acid residues Tyr1397 and Trp1436 at the distance 2.12 and 2.72Å, respectively. However, the long pentadecyl alkyl chain of CTPB produces a barrier and reducing the chance of forming hydrogen bonding with p300. The electron density ρbcp(r) of the polar bonds (C-O, C-N, C-F and C-Cl) of CTPB are increased when it present in the active site. The dipole moment of CTPB in the active site is significantly less (5.73D) when compared with the gas phase (8.16D) form. In the gas phase structure, a large region of negative electrostatic potential (ESP) is found at the vicinity of O(2) and CF3 group, which is less around the O(1) atom. Whereas, in the active site, the negative ESP around the CF3 group is decreased and increased at the O(1) and O(2)-atoms. The ESP modifications of CTPB in the active site are mainly attributed to the effect of intermolecular interaction. The gas phase and active site study insights the molecular flexibility and the electrostatic properties of CTPB in the active site.

Molecular flexibility and the electrostatic moments of curcumin and its derivatives in the active site of p300: a theoretical charge density study

A molecular docking analysis and quantum chemical calculation coupled with the charge density analysis have been carried out to understand the conformational change, charge density distribution and the electrostatic properties of HAT inhibitors curcumin and its derivatives (cinnamoyl compounds) in the active site of p300. The nearest neighbours, the shortest intermolecular contacts between the inhibitors and receptor p300; their binding energies were calculated from molecular docking analysis. A high level quantum chemical calculations were performed using density functional theory (DFT-B3LYP) with the basis set 6-311G(∗∗) combined with the theory of atoms in molecules (AIM) for the inhibitors in gas phase and in the active site of p300. It is observed that, when the molecules present in the active site of p300, relatively, their geometrical, bond topological and the electrostatic properties are significantly altered. The comparative study on the geometrical and electrostatic properties of these three inhibitors in gas phase and amino acid environment gives an insight on the molecular flexibility and the exact modification of electrostatic interaction of the inhibitor in the active site of p300. These fine details at electronic level allow to understand the exact drug-receptor interaction.

The effect of CTB on P53 protein acetylation and consequence apoptosis on MCF-7 and MRC-5 cell lines

Background:

P300 is a member of the mammalian histone acetyl transferase (HAT) family, an enzyme that acetylates histones and several non-histone proteins including P53 (the most important tumor suppressor gene) during stress, which plays an important role in the apoptosis of tumor cells. Hereby, this study describes the potency of CTB (Cholera Toxin B subunit) as a P300 activator to induce apoptosis in a breast cancer cell line (MCF-7) and a lung fibroblast cell line (MRC-5) as a non-tumorigenic control sample.

Materials and Methods:

MCF-7 and MRC-5 were cultured in RPMI-1640 and treated with or without CTB at a concentration of 85.43 μmol/L, based on half-maximal inhibitory concentration (IC50) index at different times (24, 48 and 72 h). The percentage of apoptotic cells were measured by flow cytometry. Real-time quantitative RT-PCR was performed to estimate the mRNA expression of P300 in MCF-7 and MRC-5 with CTB at different times. ELISA and Bradford protein techniques were used to detect levels of total and acetylated P53 protein generated in MCF-7 and MRC-5.

Results:

Our findings indicated that CTB could effectively induce apoptosis in MCF-7 significantly higher than MRC-5. We showed that expression of P300 was up-regulated by increasing time of CTB treatment in MCF-7 but not in MRC-5 and the acetylated and total P53 protein levels were increased more in MCF-7 cells than MRC-5.

Conclusion:

CTB could induce acetylation of P53 protein through increasing expression of P300 and consequently induce the significant cell death in MCF-7 but it could be well tolerated in MRC-5. Therefore, CTB could be used as an anti-cancer agent.

Histone acetylation as a therapeutic target

The recent developments in the field of epigenetics have changed the way the covalent modifications were perceived from mere chemical tags to important biological recruiting platforms as well as decisive factors in the process of transcriptional regulation and gene expression. Over the years, the parallel investigations in the area of epigenetics and disease have also shown the significance of the epigenetic modifications as important regulatory nodes that exhibit dysfunction in disease states. In the present scenario where epigenetic therapy is also being considered at par with the conventional therapeutic strategies, this article reviews the role of histone acetylation as an epigenetic mark involved in different biological processes associated with normal as well as abnormal gene expression states, modulation of this acetylation by small molecules and warrants the possibility of acetylation as a therapeutic target.

Inhibition of PCAF histone acetyltransferase, cytotoxicity and cell permeability of 2-acylamino-1-(3- or 4-carboxy-phenyl)benzamides

Small molecule HAT inhibitors are useful tools to unravel the role of histone acetyltransferases (HATs) in the cell and they also have relevance in oncology. We synthesized a series of 2-acylamino-1-(3- or 4-carboxyphenyl)benzamides 8–19 bearing C6, C8, C10, C12, C14, and C16 acyl chains at the 2-amino position of 2-aminobenzoic acid. Enzyme inhibition of these compounds was investigated using in vitro PCAF HAT assays. The inhibitory activities of compounds 8–10, 16, and 19 were similar to that of anacardic acid, and 17 was found to be more active than anacardic acid at 100 μM. Compounds 11–15 showed the low inhibitory activity on PCAF HAT. The cytotoxicity of the synthesized compounds was evaluated by SRB (sulforhodamine B) assay against seven human cancer cell lines: HT-29 (colon), HCT-116 (colon), MDA-231 (breast), A549 (lung), Hep3B (hepatoma), HeLa (cervical) and Caki (kidney) and one normal cell line (HSF). Compound 17 was more active than anacardic acid against human colon cancer (HCT 116, IC₅₀: 29.17 μM), human lung cancer (A549, IC₅₀: 32.09 μM) cell lines. 18 was more active than anacardic acid against human colon cancer (HT-29, IC₅₀: 35.49 μM and HCT 116, IC₅₀: 27.56 μM), human lung cancer (A549, IC₅₀: 30.69 μM), and human cervical cancer (HeLa, IC₅₀: 34.41 μM) cell lines. The apparent permeability coefficient (P_app, cm/s) values of two compounds (16 and 17) were evaluated as 68.21 and 71.48 × 10⁻⁶ cm/s by Caco-2 cell permeability assay.

Universal metal-semiconductor hybrid nanostructured SERS substrate for biosensing

We demonstrate here a novel high surface area GaN nanowall network substrate with plasmonic Ag nanodroplets, that can be employed as a highly sensitive, reproducible, and charge independent SERS substrate. The uniformity of the size and distribution of the Ag droplets and the absence of linker ligands result in large near-field intensity, while the GaN nanowall network morphology provides multiple reflections for signal enhancement. FDTD calculations simulate the observed hot-spot distribution and reiterate the higher performance of this hybrid substrate over conventional ones. Our studies on oppositely charged proteins provide a proof of concept for employing this as a versatile charge independent label free SERS substrate for trace biomolecule detection.

Probing the effect of intermolecular interaction and understanding the electrostatic moments of anacardic acid in the active site of p300 enzyme via DFT and charge density analysis

A charge density analysis has been performed on gas phase and docked forms of anacardic acid molecule to understand its charge density distribution, electrostatic moments and the conformation in the active site of p300 enzyme. Here, we report the binding affinity of anacardic acid with the p300 enzyme calculated from docking analysis. The charge density distribution of anacardic acid molecule in the gas phase as well as the docked form has been determined from the high level quantum chemical calculations using HF and DFT methods coupled with AIM theory. The charge density study on both forms of anacardic acid differentiates its structural and the electrostatic properties in different environments. When the molecule enters into the active site of p300 its conformation, charge density distribution, dipole moment and electrostatic potential are significantly altered in comparison to its gas phase structure. In the active site, the molecule adopts different conformations, its pentadecyl chain is found to be highly twisted; the charges are redistributed and the dipole moment increases from 2.37 to 3.17D. Due to the charge redistribution, the electronegative region of carboxyl group increased as it is found small in the gas phase. The comparisons between both forms reveal the flexibility of anacardic acid in the active site.

Emerging roles of anacardic acid and its derivatives: a pharmacological overview

Anacardic acid (AA) is a bioactive phytochemical found in nutshell of Anacardium occidentale. Chemically, it is a mixture of several closely related organic compounds, each consisting of salicylic acid substituted with an alkyl chain. The traditional Ayurveda depicts nutshell oil as a medicinal remedy for alexeritic, amebicidal, gingivitis, malaria and syphilitic ulcers. However, the enduring research and emerging evidence suggests that AA could be a potent target molecule with bactericide, fungicide, insecticide, anti-termite and molluscicide properties and as a therapeutic agent in the treatment of the most serious pathophysiological disorders like cancer, oxidative damage, inflammation and obesity. Furthermore, AA was found to be a common inhibitor of several clinically targeted enzymes such as NFκB kinase, histone acetyltransferase (HATs), lipoxygenase (LOX-1), xanthine oxidase, tyrosinase and ureases. In view of this, we have made an effort to summarize the ongoing research on the therapeutical role of AA and its derivatives. The current MiniReview sheds light on the pharmacological applications, toxicity and allergic responses associated with AA and its derivatives. Although the available records are promising, much more detailed investigations into the therapeutical properties, particularly the anti-cancer and anti-inflammatory activities, are urgently needed. We hope the present MiniReview will attract and encourage further research on elucidating and appreciating the possible curative properties of AA and its derivatives in the management of multifactorial diseases.