Comparative pharmacokinetics between madecassoside and asiaticoside presented in a standardised extract of Centella asiatica,ECa 233 and their respective pure compound given separately in rats

1.?ECa 233, the standardised extract of Centella asiatica, contains not less than 80% triterpenoid glycosides, in a madecassoside:asiaticoside ratio of 1.5 (±0.5):1.

2.?The pharmacokinetic comparison of madecassoside and asiaticoside was performed in rats following intravenous and oral administration of ECa 233, or an equivalent dose of the individual compounds. Blood, tissues, urine and faeces were collected after dosing to determine drug and metabolite levels using liquid chromatography–tandem mass spectrometry.

3.?Our study demonstrated that plasma levels of madecassoside, and to a lesser extent asiaticoside, were higher after administration of ECa 233 than the corresponding values for the pure compounds. There was a bidirectional interconversion between asiaticoside and madecassoside consistent with the increased exposure of madecassoside and asiaticoside in ECa 233.

4.?Both madecassoside and asiaticoside appeared to be widely distributed in several organs and metabolized extensively; following intravenous administration of either compound, approximately 80–90% of the dose was recovered as madecassic acid and asiatic acid in the faeces.     

Evolution of blood–brain barrier in brain diseases and related systemic nanoscale brain-targeting drug delivery strategies

Blood–brain barrier (BBB) strictly controls matter exchange between blood and brain, and severely limits brain penetration of systemically administered drugs, resulting in ineffective drug therapy of brain diseases. However, during the onset and progression of brain diseases, BBB alterations evolve inevitably. In this review, we focus on nanoscale brain-targeting drug delivery strategies designed based on BBB evolutions and related applications in various brain diseases including Alzheimer's disease, Parkinson's disease, epilepsy, stroke, traumatic brain injury and brain tumor. The advances on optimization of small molecules for BBB crossing and non-systemic administration routes (e.g., intranasal treatment) for BBB bypassing are not included in this review.     

Curative efficacy of purified serine protease inhibitor PTF3 from potato tuber in experimental visceral leishmaniasis

To overcome the drug toxicity and frequent resistance of parasites against the conventional drugs for the healing of human visceral leishmaniasis, innovative plant derived antileishmanial components are very imperative. Fuelled by the complications of clinically available antileishmanial drugs, a novel potato serine protease inhibitor was identified with its efficacy on experimental visceral leishmaniasis (VL). The serine protease inhibitors from potato tuber extract (PTEx) bearing molecular mass of 39 kDa (PTF1), 23 kDa (PTF2) and 17 kDa (PTF3) were purified and identified. Among them, PTF3 was selected as the most active inhibitor (IC₅₀ 143.5 ± 2.4 µg/ml) regarding its antileishmanial property. Again, intracellular amastigote load was reduced upto 83.1 ± 1.7% in pre-treated parasite and 88.5 ± 0.5% in in vivo model with effective dose of PTF3. Protective immune response by PTF3 was noted with increased production of antimicrobial substances and up-regulation of pro-inflammatory cytokines. Therapeutic potency of PTF3 is also followed by 80% survival in infected hamster. The peptide mass fingerprint (MALDI-TOF) results showed similarity of PTF3 with serine protease inhibitors database. Altogether, these results strongly propose the effectiveness of PTF3 as potent immunomodulatory therapeutics for controlling VL.     

Bioactivity and molecular docking of lactones isolated from Centaurea pseudosinaica Czerep

Two cytotoxic sesquiterpene lactones, 17-epichlorohyssopifolin A (1) and chlorjanerin (2), and a monoterpene lactone, loliolide (3) were isolated from Centaurea pseudosinaica. The cytotoxicity of the total extract and terpenoids 1–3 were evaluated against three human cancer cells (HepG2, PC-3, and HT-29), along with the human normal primary epidermal keratinocytes (HEKa) cells. With IC₅₀ values ranging between 0.6 ± 0.04 and 5.0 ± 0.61 μg/mL against HepG2; 0.2 ± 0.01 and 11.9 ± 1.31 μg/mL against PC-3, and 0.04 ± 0.013 and 8.9 ± 0.97 μg/mL against HT-29, the total extract, and lactones 1–3 demonstrated cytotoxic effects. Compound 1 displayed the strongest impact on all cancer cells and a slightly safe effect on the normal cells HEKa. Compound 1 caused accumulation of HepG2 and HT-29 cells in G1 phase as displayed cell cycle analysis. On the other hand, the cell distributions were increased in the S phase in PC-3 cells. Furthermore, 1 caused apoptosis in PC-3 and HePG2 cells with 91.50%, and 79.72 %, respectively. A higher fraction of necrotic cells was observed in HT-29 cells amounting to 23.60%. These results suggested that the promising cytotoxicity exhibited by 1 is brought by the apoptosis induction in the cancer cells, which were evaluated. As the compounds showed antiproliferative effect against the HT-29 cells, the docking simulation was performed aiming at determining how they would interact with the EGFR enzyme, whose PDB: 4I23 is considered one of the two distinct wild types of EGFR enzymes. The antibacterial activity results revealed that 3 showed the most remarkable antibacterial effects, especially against the examined Gram-positive bacteria. The total extract exhibited potent activity against all examined bacteria. The total extract showed a potent antifungal effect against two Candida and two Aspergillus pathogens. The antioxidant activity revealed the potency of the total extract and 3 as antioxidant candidates. The obtained results refer to the importance of Centaurea pseudosinaica as a source of potent antiproliferative agents and the whole plant as an antipathogenic and antioxidant agent.     

Phenolsulfonphthalein as a surrogate substrate to assess altered function of the prostaglandin transporter SLCO2A1

The prostaglandin (PG) transporter SLCO2A1 regulates PGE₂ signaling and interacts with many drugs, and SLCO2A1 defects is associated with PG metabolic disorders. This study aimed to characterize a non-metabolic phenolsulfonphthalein (PSP) transport mediated by SLCO2A1. PSP uptake by HEK293 cells expressing human SLCO2A1 (HEK/2A1 cells) was pH-independent and saturable with a K_m value of 54.5 ± 9.5 μM PGE₂ competitively inhibited PSP uptake with a K_i of 257.3 ± 22.8 nM. When PSP was intravenously (i.v.) injected, concentration-time curve showed a biphasic response. In Slco2a1-deficient (−/−) mice, AUC_inf tented to decrease and the central distribution volume (V₁) significantly increased, compared to wild-type (wt) counterparts. Intriguingly, Slco2a1-deficiency significantly reduced a ratio of tissue-to-plasma concentration in the lungs at 15 min after i.v. injection, suggesting that SLCO2A1 limits tissue distribution of PSP. In conclusion, these results prove that PSP is a potential surrogate for monitoring SLCO2A1 function, providing a new concept for diagnostics for the genetic diseases caused by defects in SLCO2A1 gene.     

Design of a Novel Nucleus-Targeted NLS-KALA-SA Nanocarrier to Delivery Poorly Water-Soluble Anti-Tumor Drug for Lung Cancer Treatment

In this study, we designed a novel nucleus-targeted nanocarrier (NLS-KALA-SA, NKSN) consisting of Kala peptide (KALA), nuclear localization signal (NLS) and stearic acid (SA) using Fmoc solid phase synthesis method. We chose Curcumin (CUR), Paclitaxel (PTX), Ginsenoside compound K(CK) as models of poorly water-soluble antitumor drugs, The drugs loaded NLS-KALA-SA nanoparticles (CUR/NKSN, PTX/NKSN, CK/NKSN) were obained by the dialysis method, their physicochemical properties were determined and antitumor activity were evaluated. The NLS-KALA-SA nanoparticles were spherical shaped with an average size of 76.4 ± 7.6 mm and a zeta potential of 43.7 ± 5.8 mV. The drug-loaded NLS-KALA-SA nanoparticles were above 86.1% and 17.1% in entrapment efficiency and drug loading capacity, and had sustained drug release behavior. Biodistribution and cellular uptake study exhibited that PTX/NKSN mainly distributed in tumor site of A549-bearing mice, and coumarin-6(C6) loaded NLS-KALA-SA nanoparticle (C6/NKSN) was predominantly accumulated in the nucleus of A549 cells. Western blot analysis indicated that PTX/NKSN could more remarkably inhibit Bcl-2 expression and enhance the expression of Bax and Caspase-3 as compared to the controls in A549 cells. Cell apoptosis and antitumor activity study showed that PXT/NKSN could more obviously induce apoptosis of A549 cells compared with free PXT, the PTX/NKSN administration was more effective than free PTX for lung cancer treatment and displayed mild toxicity in A549-bearing mice. The results demonstrates that the NLS-KALA-SA nanoparticles system could enhance the antitumor effects of the encapsulated drug and reduce tissue toxicity due to its long circulating properties and tumor targeting, which might provide a promising strategy for lung cancer treatment.     

Selective inhibition of interleukin-1 receptor-associated kinase 1 ameliorates lipopolysaccharide-induced sepsis in mice

Interleukin-1 receptor-associated kinases (IRAKs), particularly IRAK1 and IRAK4, are important in transducing signal from Toll-like receptor 4. We interrogated if a selective inhibition of IRAK1 could alleviate lipopolysaccharide (LPS)-induced sepsis. In this study, we tested the impact of a novel selective IRAK1 inhibitor Jh-X-119-01 on LPS-induced sepsis in mice. Survival at day 5 was 13.3% in control group where septic mice were treated by vehicle, while the values were 37.5% (p = 0.046, vs. control) and 56.3% (p = 0.003, vs. control) for 5 mg/kg and 10 mg/kg Jh-X-119-01-treated mice. Jh-X-119-01 alleviated lung injury and reduced production of TNFα and IFNγ in peritoneal macrophages. Jh-X-119-01 decreased phosphorylation of NF-κB and mRNA levels of IL-6 and TNFα in LPS-treated macrophages in vitro. Jh-X-119-01 selectively inhibited IRAK1 phosphorylation comparing with a non-selective IRAK1/4 inhibitor which simultaneously inhibited phosphorylation of IRAK1 and IRAK4. Both Jh-X-119-01 and IRAK1/4 inhibitor increased survival of septic mice, but Jh-X-119-01-treated mice had higher blood CD11b⁺ cell counts than IRAK1/4 inhibitor-treated ones [24 h: (1.18 ± 0.26) × 10⁶/ml vs. (0.79 ± 0.20) × 10⁶/ml, p = 0.001; 48 h: (1.00 ± 0.30) × 10⁶/ml vs. (0.67 ± 0.23) × 10⁶/ml, p = 0.042]. IRAK1/4 inhibitor induced more apoptosis of macrophages than Jh-X-119-01 did in vitro. IRAK1/4 inhibitor decreased protein levels of anti-apoptotic BCL-2 and MCL-1 in RAW 264.7 and THP-1 cells, an effect not seen in Jh-X-119-01-treated cells. In conclusion, Jh-X-119-01 selectively inhibited activation of IRAK1 and protected mice from LPS-induced sepsis. Jh-X-119-01 showed less toxicity on macrophages comparing with a non-selective IRAK1/4 inhibitor.     

Discovery of [1,2,3]triazolo[4,5-d]pyrimidine derivatives as highly potent,selective, and cellularly active USP28 inhibitors

Ubiquitin specific peptidase 28 (USP28) is closely associated to the occurrence and development of various malignancies, and thus has been validated as a promising therapeutic target for cancer therapy. To date, only few USP28 inhibitors with moderate inhibitory activity have been reported, highly potent and selective USP28 inhibitors with new chemotypes remain to be discovered for pathologically investigating the roles of deubiquitinase. In this current study, we reported the synthesis and biological evaluation of new [1,2,3]triazolo[4,5-d]pyrimidine derivatives as potent USP28 inhibitors. Especially, compound 19 potently inhibited USP28 (IC₅₀ = 1.10 ± 0.02 μmol/L, K_d = 40 nmol/L), showing selectivity over USP7 and LSD1 (IC₅₀ > 100 μmol/L). Compound 19 was cellularly engaged to USP28 in gastric cancer cells. Compound 19 reversibly bound to USP28 and directly affected its protein levels, thus inhibiting the proliferation, cell cycle at S phase, and epithelial-mesenchymal transition (EMT) progression in gastric cancer cell lines. Docking studies were performed to rationalize the potency of compound 19. Collectively, compound 19 could serve as a new tool compound for the development of new USP28 inhibitors for exploring the roles of deubiquitinase in cancers.     

In vitro inhibitory effects of components from Salvia miltiorrhiza on catalytic activity of three human Arachidonic acid ω-hydroxylases

CYP4 enzymes are involved in the metabolism of xenobiotics and endogenous molecules. 20-Hydroxyeicosatetraenoic acid (20-HETE), the arachidonic acid (AA) ω-hydroxylation metabolite catalyzed by CYP4A/4F enzymes, is implicated in various biological functions. The goal of this investigation is to examine the inhibitory effects of components from Salvia miltiorrhiza(Danshen) on AA ω-hydroxylation using recombinant CYP4A11, CYP4F2, CYP4F3B, and microsomal systems. Tanshinone IIA had noncompetitive inhibition on CYP4F3B (K_i = 4.98 μM). Cryptotanshinone (K_i = 6.87 μM) and tanshinone I (K_i = 0.42 μM) had mixed-type inhibition on CYP4A11. Dihydrotanshinone I had mixed-type inhibition on CYP4A11 (K_i = 0.09 μM), and noncompetitive inhibition on CYP4F2 (K_i = 4.25 μM) and CYP4F3B (K_i = 3.08 μM). Salvianolic acid A had competitive inhibition on CYP4A11 (K_i = 19.37 μM), and noncompetitive inhibition on CYP4F2 (K_i = 15.28 μM) and CYP4F3B (K_i = 6.45 μM). Salvianolic acid C had noncompetitive inhibition on CYP4F2 (K_i = 5.70 μM) and CYP4F3B (K_i = 18.64 μM). In human kidney, human liver or rat heart microsomes, 20-HETE formation was significantly inhibited (P < 0.05) by dihydrotanshinone I (5 and 20 μM) and salvianolic acid A (20 and 50 μM). Given that low plasma concentrations of Danshen components after oral administration, Danshen preparations may not play pharmacological roles by inhibiting AA ω-hydroxylases; however, as Danshen components may reach high concentration in human intestine, drugs that have an important pre-systemic metabolism by these CYP4A/4F enzymes should avoid being co-administered with Danshen preparations.     

TIMP1 preserves the blood–brain barrier through interacting with CD63/integrin β1 complex and regulating downstream FAK/RhoA signaling

Blood–brain barrier (BBB) breakdown and the associated microvascular hyperpermeability are hallmark features of several neurological disorders, including traumatic brain injury (TBI). However, there is no viable therapeutic strategy to rescue BBB function. Tissue inhibitor of metalloproteinase-1 (TIMP1) has been considered to be beneficial for vascular integrity, but the molecular mechanisms underlying the functions of TIMP1 remain elusive. Here, we report that TIMP1 executes a protective role on neuroprotective function via ameliorating BBB disruption in mice with experimental TBI. In human brain microvessel endothelial cells (HBMECs) exposed to hypoxia and inflammation injury, the recombinant TIMP1 (rTIMP1) treatment maintained integrity of junctional proteins and trans-endothelial tightness. Mechanistically, TIMP1 interacts with CD63/integrin β1 complex and activates downstream FAK signaling, leading to attenuation of RhoA activation and F-actin depolymerization for endothelial cells structure stabilization. Notably, these effects depend on CD63/integrin β1 complex, instead of the MMP-inhibitory function. Together, our results identified a novel MMP-independent function of TIMP1 in regulating endothelial barrier integrity. Therapeutic interventions targeting TIMP1 and its downstream signaling may be beneficial to protect BBB function following brain injury and neurological disorders.     

Phyllanthus emblica (Amla) methanolic extract regulates multiple checkpoints in 15-lipoxygenase mediated inflammopathies: Computational simulation and in vitro evidence

Amla (Phyllanthus emblica) has long been used in traditional folk medicine to prevent and cure a variety of inflammatory diseases. In this study, the antioxidant activity (DPPH scavenging and reducing power), anti-inflammatory activity (RBC Membrane Stabilization and 15-LOX inhibition), and anticoagulation activity (Serin protease inhibition and Prothrombin Time assays) of the methanolic extract of amla were conducted. Amla exhibited a substantial amount of phenolic content (TPC: 663.53 mg GAE/g) and flavonoid content (TFC: 418.89 mg GAE/g). A strong DPPH scavenging effect was observed with an IC₅₀ of 311.31 µg/ml as compared to standard ascorbic acid with an IC₅₀ of 130.53 µg/ml. In reducing power assay, the EC₅₀ value of the extract was found to be 196.20 µg/ml compared to standard ascorbic acid (EC₅₀ = 33.83 µg/ml). The IC₅₀ value of the RBC membrane stabilization and 15-LOX assays was observed as 101.08 µg/ml (IC₅₀ of 58.62 µg/ml for standard aspirin) and 195.98 µg/ml (IC₅₀ of 19.62 µg/ml for standard quercetin), respectively. The extract also strongly inhibited serine protease (trypsin) activity with an IC₅₀ of 505.81 µg/ml (IC₅₀ of 295.44 µg/ml for standard quercetin). The blood coagulation time (PTT) was found to be 11.91 min for amla extract and 24.11 min for standard Warfarin. Thus, the findings of an in vitro study revealed that the methanolic extract of amla contains significant antioxidant, anti-inflammatory, and anticoagulation activity. Furthermore, in silico docking and simulation of reported phytochemicals of amla with human 15-LOXA and 15-LOXB were carried out to validate the anti-inflammatory activity of amla. In this analysis, epicatechin and catechin showed greater molecular interaction and were considerably stable throughout the 100 ns simulation with 15-lipoxygenase A (15-LOXA) and 15-lipoxygenase B (15-LOXB) respectively.     

Galactosylated Chitosan Coated Liposomes of Ledipasvir for Liver Targeting: Chemical Synthesis,Statistical Optimization,In-vitro and In-vivo evaluation

Ledipasvir is a novel antiviral agent used in the treatment of hepatitis C. We aim in our study to increase its delivery to hepatocytes and prolong its retention within liver. Several formulae of ledipasvir loaded liposomes were prepared and the best formula regarding particle size, zeta potential, polydispersity index and entrapment efficiency was selected. On the other hand, galactosylated chitosan was synthesized in a chemical reaction. Then the best liposomes formula was coated with the galactosylated chitosan. Having galactose residues on their surface, the coated liposomes can bind to the asialoglycoprotein receptors on the targeted hepatocytes enhancing ledipasvir uptake into them. The galactosylated chitosan coated liposomes had particle size of 218.2 nm ± 7.21, zeta potential of 27.15 mV ± 1.76, polydispersity index of 0.278 ± 0.055 and entrapment efficiency % of 54.63% ± 0.05 respectively. The pharmacokinetic study revealed a significant increase in the liver peak concentration (C_max) and the area under liver concentration versus time curve AUC_(0–72 h) and significant prolongation in the liver terminal half life (t½) and mean residence time (MRT) in comparison to the oral dispersion of ledipasvir with values of 11,400 ng/g, 88,855 ng1h/g, 32.00 h and 18.11 h respectively.     

The effect of drug loading and multiple administration on the protein corona formation and brain delivery property of PEG-PLA nanoparticles

The presence of protein corona on the surface of nanoparticles modulates their physiological interactions such as cellular association and targeting property. It has been shown that α-mangostin (αM)-loaded poly(ethylene glycol)-poly(l-lactide) (PEG-PLA) nanoparticles (NP-αM) specifically increased low density lipoprotein receptor (LDLR) expression in microglia and improved clearance of amyloid beta (Aβ) after multiple administration. However, how do the nanoparticles cross the blood?brain barrier and access microglia remain unknown. Here, we studied the brain delivery property of PEG-PLA nanoparticles under different conditions, finding that the nanoparticles exhibited higher brain transport efficiency and microglia uptake efficiency after αM loading and multiple administration. To reveal the mechanism, we performed proteomic analysis to characterize the composition of protein corona formed under various conditions, finding that both drug loading and multiple dosing affect the composition of protein corona and subsequently influence the cellular uptake of nanoparticles in b.End3 and BV-2 cells. Complement proteins, immunoglobulins, RAB5A and CD36 were found to be enriched in the corona and associated with the process of nanoparticles uptake. Collectively, we bring a mechanistic understanding about the modulator role of protein corona on targeted drug delivery, and provide theoretical basis for engineering brain or microglia-specific targeted delivery system.     

UM171 promotes expansion of autologous peripheral blood hematopoietic stem cells from poorly mobilizing lymphoma patients

BackgroundAutologous hematopoietic stem cell transplantation is an effective therapeutic strategy for lymphoma patients. However, some patients have to give up receiving transplantation because of failing to obtain sufficient CD34⁺ cells yields. Therefore, we ex vivo expanded HSCs of lymphoma patients using UM171 to solve the problem of HSCs deficiency.MethodsMobilized peripheral blood-derived CD34⁺ cells from lymphoma patients were cultured for 10 days with or without UM171. The fold of cell expansion and the immunophenotype of expanded cells were assessed by flow cytometry. RNA-seq experiment was performed to identify the mechanism by which UM171 promoted HSCs expansion.ResultsUM171 treatment increased the proportion of CD34⁺ (68.97 ± 6.91%), CD34⁺ CD38⁻ cells (44.10 ± 9.20%) and CD34⁺CD38⁻CD45RA⁻CD90⁺ LT-HSCs (3.05 ± 2.08%) compared to vehicle treatment (36.08 ± 11.14%, 18.30 ± 9.49% and 0.56 ± 0.45%, respectively). UM171 treatment led to an 85.08-fold increase in LT-HSC numbers relative to initial cells. Importantly, UM171 promoted expansion of LT-HSCs achieved 138.57-fold in patients with poor mobilization. RNA-seq data showed that UM171 upregulated expression of HSC-, mast cell-specific genes and non-canonical Wnt signaling related genes, and inhibited genes expression of erythroid, megakaryocyte and inflammatory mediated chemokine.ConclusionsOur study shows that UM171 can efficiently promote ex vivo expansion of HSCs from lymphoma patients, especially for poorly mobilizing patients. In terms of mechanism, UM171 upregulate HSC-specific genes expression and suppress erythroid and megakaryocytic differentiation, as well as activate non-classical Wnt signaling.     

Hepatotoxicity reports in the FDA adverse event reporting system database: A comparison of drugs that cause injury via mitochondrial or other mechanisms

Drug-induced liver injury (DILI) is a leading reason for preclinical safety attrition and post-market drug withdrawals. Drug-induced mitochondrial toxicity has been shown to play an essential role in various forms of DILI, especially in idiosyncratic liver injury. This study examined liver injury reports submitted to the Food and Drug Administration (FDA) Adverse Event Reporting System (FAERS) for drugs associated with hepatotoxicity via mitochondrial mechanisms compared with non-mitochondrial mechanisms of toxicity. The frequency of hepatotoxicity was determined at a group level and individual drug level. A reporting odds ratio (ROR) was calculated as the measure of effect. Between the two DILI groups, reports for DILI involving mitochondrial mechanisms of toxicity had a 1.43 (95% CI 1.42–1.45; P < 0.0001) times higher odds compared to drugs associated with non-mitochondrial mechanisms of toxicity. Antineoplastic, antiviral, analgesic, antibiotic, and antimycobacterial drugs were the top five drug classes with the highest ROR values. Although the top 20 drugs with the highest ROR values included drugs with both mitochondrial and non-mitochondrial injury mechanisms, the top four drugs (ROR values > 18: benzbromarone, troglitazone, isoniazid, rifampin) were associated with mitochondrial mechanisms of toxicity. The major demographic influence for DILI risk was also examined. There was a higher mean patient age among reports for drugs that were associated with mitochondrial mechanisms of toxicity [56.1 ± 18.33 (SD)] compared to non-mitochondrial mechanisms [48 ± 19.53 (SD)] (P < 0.0001), suggesting that age may play a role in susceptibility to DILI via mitochondrial mechanisms of toxicity. Univariate logistic regression analysis showed that reports of liver injury were 2.2 (odds ratio: 2.2, 95% CI 2.12–2.26) times more likely to be associated with older patient age, as compared with reports involving patients less than 65 years of age. Compared to males, female patients were 37% less likely (odds ratio: 0.63, 95% CI 0.61–0.64) to be subjects of liver injury reports for drugs associated with mitochondrial toxicity mechanisms. Given the higher proportion of severe liver injury reports among drugs associated with mitochondrial mechanisms of toxicity, it is essential to understand if a drug causes mitochondrial toxicity during preclinical drug development when drug design alternatives, more clinically relevant animal models, and better clinical biomarkers may provide a better translation of drug-induced mitochondrial toxicity risk assessment from animals to humans. Our findings from this study align with mitochondrial mechanisms of toxicity being an important cause of DILI, and this should be further investigated in real-world studies with robust designs.     

Evodiamine-inspired dual inhibitors of histone deacetylase 1 (HDAC1) and topoisomerase 2 (TOP2) with potent antitumor activity

A great challenge in multi-targeting drug discovery is to identify drug-like lead compounds with therapeutic advantages over single target inhibitors and drug combinations. Inspired by our previous efforts in designing antitumor evodiamine derivatives, herein selective histone deacetylase 1 (HDAC1) and topoisomerase 2 (TOP2) dual inhibitors were successfully identified, which showed potent in vitro and in vivo antitumor potency. Particularly, compound 30a was orally active and possessed excellent in vivo antitumor activity in the HCT116 xenograft model (TGI = 75.2%, 150 mg/kg, p.o.) without significant toxicity, which was more potent than HDAC inhibitor vorinostat, TOP inhibitor evodiamine and their combination. Taken together, this study highlights the therapeutic advantages of evodiamine-based HDAC1/TOP2 dual inhibitors and provides valuable leads for the development of novel multi-targeting antitumor agents.     

Design of semisynthetic derivatives of the Amaryllidaceae alkaloid ambelline and exploration of their in vitro cytotoxic activities

Ambelline, an alkaloid from the Amaryllidaceae family with a crinane-type skeleton, has not yet demonstrated any outstanding biological activity. However, its analogues prepared by derivatization of the C-11 hydroxyl group show different interesting effects. Continuing our earlier work, twelve novel aromatic esters were developed (10, 14, 16, 17, 22–25, 30–33) and studied, together with previously synthesized derivatives (2–9, 11–13, 15, 18–21, 26–29) in terms of their cytotoxic activity. The cytotoxic potential was determined on a panel of nine human cancer cell lines and one noncancerous cell line to characterize their biological activity spectrum. To describe and foresee the structure–activity relationship for further research, substances synthesized and described in our previous work were also included in this cytotoxicity study. The most significant activity was associated with analogues having methyl (10), methoxy (14–17), or ethoxy (18) substitution on the phenyl condensed to ambelline. However, the 4-chloro-3-nitrobenzoyl derivative (32) showed the most promising IC₅₀ values, ranging from 0.6 ± 0.1 µM to 9.9 ± 0.2 µM. In vitro cytotoxicity studies indicated the most potent antiproliferative activity of 32 in a dose-dependent and time-dependent manner. Besides, 32 was found to be effective in decreasing viability and triggering apoptosis of MOLT-4 T-lymphoblastic leukemia cells.