Simultaneous Regulation of the Mechanical/Osteogenic Capacity of Brushite Calcium Phosphate Cement by Incorporating with Poly(ethylene glycol) Dicarboxylic Acid.

Brushite calcium phosphate cement (brushite CPC) is a prospective bone repair material due to its ideal resorption rates in vivo. However, the undesirable mechanical property and bioactivity limited its availability in clinic application. To address this issue, incorporating polymeric additives has emerged as a viable solution. In this study, poly(ethylene glycol) dicarboxylic acid, PEG(COOH), was synthesized and employed as the polymeric additive. The setting behavior, anti-washout ability, mechanical property, degradation rate, and osteogenic capacity of brushite CPC were regulated by incorporating PEG(COOH). The incorporation of PEG(COOH) with carboxylic acid groups demonstrated a positive effect on both mechanical properties and osteogenic activity in bone repair. This study offers valuable insights and suggests a promising strategy for the development of materials in bone tissue engineering.

The biochemistry and physiology of long-chain dicarboxylic acid metabolism.

Mitochondrial ß-oxidation is the most prominent pathway for fatty acid oxidation but alternative oxidative metabolism exists. Fatty acid ω-oxidation is one of these pathways and forms dicarboxylic acids as products. These dicarboxylic acids are metabolized through peroxisomal ß-oxidation representing an alternative pathway, which could potentially limit the toxic effects of fatty acid accumulation. Although dicarboxylic acid metabolism is highly active in liver and kidney, its role in physiology has not been explored in depth. In this review, we summarize the biochemical mechanism of the formation and degradation of dicarboxylic acids through ω- and ß-oxidation, respectively. We will discuss the role of dicarboxylic acids in different (patho)physiological states with a particular focus on the role of the intermediates and products generated through peroxisomal ß-oxidation. This review is expected to increase the understanding of dicarboxylic acid metabolism and spark future research.

Bempedoic acid for nonalcoholic fatty liver disease: evidence and mechanisms of action.

PURPOSE OF REVIEW: Nonalcoholic fatty liver disease (NAFLD) is a highly prevalent progressive condition that lacks a specific pharmacological treatment. ATP-citrate lyase (ACLY) is one of the emergent targets for the treatment of NAFLD. This review aims to summarize the role of ACLY in NAFLD, provide evidence of the beneficial effects of the ACLY inhibitor bempedoic acid (BemA) in NAFLD and discuss the mechanisms involved. RECENT FINDINGS: BemA is effective in reducing hepatic steatosis in several animal models that recapitulate different stages of the disease. Thus, in a dietary model of simple hepatic steatosis in female rats, BemA abrogates the accumulation of liver fat. Apart from ACLY inhibition, BemA has several functions in the liver that contribute to the antisteatotic effect: inhibition of ketohexokinase, induction of patatin-like phospholipase domain-containing protein 3 and increases in both fatty acid ß-oxidation activity and hepatic H 2 S production. In models of the advanced phases of NAFLD, BemA reduces not only steatosis, but also ballooning, lobular inflammation and hepatic fibrosis, by mechanisms involving both hepatocytes and hepatic stellate cells. SUMMARY: BemA, an ACLY inhibitor currently approved for the treatment of hypercholesterolemia, may be a useful drug to treat NAFLD through its antisteatotic, anti-inflammatory and antifibrotic effects.

Synthesis, crystal structure, herbicidal activity and mode of action of new cyclopropane-1,1-dicarboxylic acid analogues.

A new series of cyclopropane-1,1-dicarboxylic (CPD) acid analogues were designed and synthesized. CPD is an inhibitor of ketol-acid reductoisomerase (KARI), an enzyme of the branched chain amino acid pathway in plants. The structures of CPD analogues were characterized by 1H NMR and HRMS. The structure of N,N'-bis(4-(tert-butyl)phenyl)cyclopropane-1,1-dicarboxamide was further elucidated by X-ray diffraction. The herbicidal activities of these compounds were tested against lettuce (Lactuca sativa) and bentgrass (Agrostis stolonifera). Most of these compounds exhibited low herbicidal activity against both plant species. Among them, N,N'-bis(2-ethylphenyl)cyclopropane-1,1-dicarboxamide displayed moderate activity against bentgrass. Inhibition of KARI activity by the CPD analogues was also assessed experimentally and by molecular docking simulation with results supporting inhibition of KARI as their mode of action. These results provide the basis for design of more effective KARI inhibitors.

Aerosol-Administered Adelmidrol Attenuates Lung Inflammation in a Murine Model of Acute Lung Injury.

Acute lung injury (ALI) is a common and devastating clinical disorder with a high mortality rate and no specific therapy. The pathophysiology of ALI is characterized by increased alveolar/capillary permeability, lung inflammation, oxidative stress and structural damage to lung tissues, which can progress to acute respiratory distress syndrome (ARDS). Adelmidrol (ADM), an analogue of palmitoylethanolamide (PEA), is known for its anti-inflammatory and antioxidant functions, which are mainly due to down-modulating mast cells (MCs) and promoting endogenous antioxidant defense. The aim of this study is to evaluate the protective effects of ADM in a mice model of ALI, induced by intratracheal administration of lipopolysaccharide (LPS) at the dose of 5 mg/kg. ADM 2% was administered by aerosol 1 and 6 h after LPS instillation. In this study, we clearly demonstrated that ADM reduced lung damage and airway infiltration induced by LPS instillation. At the same time, ADM counteracted the increase in MC number and the expression of specific markers of MC activation, i.e., chymase and tryptase. Moreover, ADM reduced oxidative stress by upregulating antioxidant enzymes as well as modulating the Nf-kB pathway and the resulting pro-inflammatory cytokine release. These results suggest that ADM could be a potential candidate in the management of ALI.

Glucose protects the cell membrane, Na+/K+-ATPase, nucleic acids, and proteins in Bacillus subtilis spores under high pressure thermal sterilization.

The extreme resistance of bacterial spores to sterilization makes them a major concern to the food industry and consumers. In this study, the effect of glucose on the inactivation of Bacillus subtilis spores by high pressure thermal sterilization (HPTS) was evaluated. The results showed that the protective effects of glucose increased with the increase in its concentration. Compared with the HPTS control (no addition of glucose), the activity of Na+/K+-ATPase was increased, the leakage of proteins and the release of 2,6-pyridine dicarboxylic acid (DPA) was decreased, and the vibrational strength of the functional group P = O was reduced by the addition of glucose. At the same time, glucose treatment increased the content of α-helix by 6%-22%, while decreased the random coil content by 5%-13% of the cellular protein. In conclusion, the addition of glucose protected the cell membrane, Na+/K+-ATPase, cellular nucleic acids and proteins of B. subtilis under HPTS treatment.

An Update on New Cholesterol Inhibitor: Bempedoic Acid.

An increase in the level of cholesterol day by day is easily seen in most people just because of poor life style, food with high cholesterol, lack of physical work, etc. There are lots of molecules available, which lower down the cholesterol level. In this field a new molecule has been introduced that is bimpedoic acid. Researches indicate that bempedoic acid has the same mechanism of action as statins, which means that it also inhibits the HMG-CoA reductase enzyme. This article is my best collection of published scientific data on bempedoic acid till now. It also includes the chemistry, pharmacodynamic and pharmacokinetic parameters of the mentioned new molecule.

Statins and Bempedoic Acid: Different Actions of Cholesterol Inhibitors on Macrophage Activation.

Statins represent the most prescribed class of drugs for the treatment of hypercholesterolemia. Effects that go beyond lipid-lowering actions have been suggested to contribute to their beneficial pharmacological properties. Whether and how statins act on macrophages has been a matter of debate. In the present study, we aimed at characterizing the impact of statins on macrophage polarization and comparing these to the effects of bempedoic acid, a recently registered drug for the treatment of hypercholesterolemia, which has been suggested to have a similar beneficial profile but fewer side effects. Treatment of primary murine macrophages with two different statins, i.e., simvastatin and cerivastatin, impaired phagocytotic activity and, concurrently, enhanced pro-inflammatory responses upon short-term lipopolysaccharide challenge, as characterized by an induction of tumor necrosis factor (TNF), interleukin (IL) 1ß, and IL6. In contrast, no differences were observed under long-term inflammatory (M1) or anti-inflammatory (M2) conditions, and neither inducible NO synthase (iNOS) expression nor nitric oxide production was altered. Statin treatment led to extracellular-signal regulated kinase (ERK) activation, and the pro-inflammatory statin effects were abolished by ERK inhibition. Bempedoic acid only had a negligible impact on macrophage responses when compared with statins. Taken together, our data point toward an immunomodulatory effect of statins on macrophage polarization, which is absent upon bempedoic acid treatment.

Activation of ectopic olfactory receptor 544 induces GLP-1 secretion and regulates gut inflammation.

Olfactory receptors are ectopically expressed in extra-nasal tissues. The gut is constantly exposed to high levels of odorants where ectopic olfactory receptors may play critical roles. Activation of ectopic olfactory receptor 544 (Olfr544) by azelaic acid (AzA), an Olfr544 ligand, reduces adiposity in mice fed a high-fat diet (HFD) by regulating fuel preference to fats. Herein, we investigated the novel function of Olfr544 in the gut. In GLUTag cells, AzA induces the cAMP-PKA-CREB signaling axis and increases the secretion of GLP-1, an enteroendocrine hormone with anti-obesity effects. In mice fed a HFD and orally administered AzA, GLP-1 plasma levels were elevated in mice. The induction of GLP-1 secretion was negated in cells with Olfr544 gene knockdown and in Olfr544-deficient mice. Gut microbiome analysis revealed that AzA increased the levels of Bacteroides acidifaciens and microbiota associated with antioxidant pathways. In fecal metabolomics analysis, the levels of succinate and trehalose, metabolites correlated with a lean phenotype, were elevated by AzA. The function of Olfr544 in gut inflammation, a key feature in obesity, was further investigated. In RNA sequencing analysis, AzA suppressed LPS-induced activation of inflammatory pathways and reduced TNF-α and IL-6 expression, thereby improving intestinal permeability. The effects of AzA on the gut metabolome, microbiome, and colon inflammation were abrogated in Olfr544-KO mice. These results collectively demonstrated that activation of Olfr544 by AzA in the gut exerts multiple effects by regulating GLP-1 secretion, gut microbiome and metabolites, and colonic inflammation in anti-obesogenic phenotypes and, thus, may be applied for obesity therapeutics.

Greater than expected reduction in low-density lipoprotein-cholesterol (LDL-C) with bempedoic acid in a patient with heterozygous familial hypercholesterolemia (HeFH).

Bempedoic acid is an adenosine triphosphate-citrate lyase (ACL) inhibitor that reduces levels of low-density lipoprotein-cholesterol (LDL-C) in the plasma by inhibition of cholesterol synthesis in hepatic cells, which leads to up-regulation of hepatic LDL receptors. Bempedoic acid is approved as an adjunct to diet and maximally tolerated statin therapy for the treatment of adults with heterozygous familial hypercholesterolemia (HeFH) who require additional lowering of LDL-C. In this case study, we describe a patient with HeFH who had a prior excellent response to statin but unable to take the same, and a less than expected response to PCSK9i, in whom initiation of bempedoic acid led to a substantial reduction of LDL-C. Our findings suggest that patients who are quite responsive to statins may also be quite responsive to bempedoic acid, a medication that works in the same biochemical pathway as HMG-CoA reductase inhibitors. Additionally, this medication may be particularly effective at lowering LDL-C among individuals not on background statin therapy.

Novel betulin dicarboxylic acid ester derivatives as potent antiviral agents: Design, synthesis, biological evaluation, structure-activity relationship and in-silico study.

The search for new methods of antiviral therapy is primarily focused on the use of substances of natural origin. In this context, a triterpene compound, betulin 1, proved to be a good starting point for derivatization. Thirty-eight betulin acid ester derivatives were synthetized, characterized, and tested against DNA and RNA viruses. Several compounds exhibited 4- to 11-fold better activity against Enterovirus E (compound 5 EC50: 10.3 µM) and 3- to 6-fold better activity against Human alphaherpesvirus 1 (HHV-1; compound 3c EC50: 17.2 µM). Time-of-addition experiments showed that most of the active compounds acted in the later steps of the virus replication cycle (e.g., nucleic acid/protein synthesis). Further in-silico analysis confirmed in-vitro data and demonstrated that interactions between HHV-1 DNA polymerase and the most active compound, 3c, were more stable than interactions with the parent non-active betulin 1.

Absence of effect of steady state bempedoic acid on cardiac repolarization: Results of a thorough QT/QTc study in healthy volunteers.

Bempedoic acid is an inhibitor of adenosine triphosphate-citrate lyase approved for use in adults with hypercholesterolemia. Nonclinical studies assessed binding to the human ether-a-go-go-related gene (hERG) potassium channel in vitro and the effect of bempedoic acid on QT/QTc in cynomolgus monkeys. A randomized, double-blind, parallel-design clinical study assessed the effects of steady-state bempedoic acid at a supratherapeutic dose (240 mg/day, 33.3% higher the180 mg/day therapeutic dose), placebo, and moxifloxacin (400 mg) in healthy subjects. In vitro binding potency for bempedoic acid to the hERG potassium channel was weak, with half-maximal inhibition (IC50 ) estimated at greater than 1000 µM (>1670-fold the bempedoic acid 180 mg/day steady-state unbound maximum concentration). In monkeys, individual rate-corrected QT intervals showed no time- or dose-dependent changes up to 100 mg/kg of bempedoic acid. In human subjects, the upper 90% confidence interval (CI) for the difference in QTc interval, corrected using Fridericia's formula (QTcF), between bempedoic acid and placebo was less than 5 msec at all time points. Concentration-QTcF analysis showed that maximum bempedoic acid concentration at steady-state was attained at a median 2.1 h postdose, and the predicted mean change (90% CI) in QTcF at the observed mean bempedoic acid concentration 2 h postdose was -0.5 (-5.0, 4.0) msec. The lower bound of the moxifloxacin 90% CI exceeded 5 msec at prespecified time points, establishing study sensitivity. Steady-state bempedoic acid at a supratherapeutic dose of 240 mg was generally well-tolerated and not associated with QTc prolongation in healthy subjects.

Hypoxia-Responsive Gene Editing to Reduce Tumor Thermal Tolerance for Mild-Photothermal Therapy.

Near-infrared (NIR)-light-triggered photothermal therapy (PTT) is usually associated with undesirable damage to healthy organs nearby due to the high temperatures (>50 °C) available for tumor ablation. Low-temperature PTT would therefore have tremendous value for clinical application. Here, we construct a hypoxia-responsive gold nanorods (AuNRs)-based nanocomposite of CRISPR-Cas9 for mild-photothermal therapy via tumor-targeted gene editing. AuNRs are modified with azobenzene-4,4'-dicarboxylic acid (p-AZO) to achieve on-demand release of CRISPR-Cas9 using hypoxia-responsive azo bonds. In the hypoxic tumor microenvironment, the azo groups of the hypoxia-activated CRISPR-Cas9 nanosystem based on gold nanorods (APACPs) are selectively reduced by the overexpression of reductases, leading to the release of Cas9 and subsequent gene editing. Owing to the knockout of HSP90α for reducing the thermal resistance of cancer cells, highly effective tumor ablation both in vitro and in vivo was achieved with APACPs under mild PTT.

Downregulation of FABP5 Suppresses the Proliferation and Induces the Apoptosis of Gastric Cancer Cells Through the Hippo Signaling Pathway.

Fatty acid binding protein 5 (FABP5) has been reported to play an important role in various cancers. We found that high FABP5 expression was associated with poor histological differentiation and vascular invasion. High FABP5 expression indicated a poor prognosis. Downregulation of FABP5 suppressed cell proliferation, cell migration and invasion, and induced cell apoptosis. Bioinformatic analysis revealed that the Hippo signaling pathway was related to FABP5. We found that overexpression of yes-associated protein 1 (YAP1) could partially reverse the effect of FABP5 knockdown on growth and apoptosis. The FABP5 inhibitor SBFI-26 suppressed the proliferation and promoted the apoptosis of gastric cancer (GC) cells and interfered with the Hippo signaling pathway by inhibiting YAP1. Our data suggested that FABP5 might act as a potential target associated with the Hippo signaling pathway for GC treatment.

IGF1-mediated HOXA13 overexpression promotes colorectal cancer metastasis through upregulating ACLY and IGF1R.

Metastasis is the major reason for the high mortality of colorectal cancer (CRC) patients and its molecular mechanism remains unclear. Here, we report a novel role of Homeobox A13 (HOXA13), a member of the Homeobox (HOX) family, in promoting CRC metastasis. The elevated expression of HOXA13 was positively correlated with distant metastasis, higher AJCC stage, and poor prognosis in two independent CRC cohorts. Overexpression of HOXA13 promoted CRC metastasis whereas downregulation of HOXA13 suppressed CRC metastasis. Mechanistically, HOXA13 facilitated CRC metastasis by transactivating ATP-citrate lyase (ACLY) and insulin-like growth factor 1 receptor (IGF1R). Knockdown of ACLY and IGFIR inhibited HOXA13-medicated CRC metastasis, whereas ectopic overexpression of ACLY and IGFIR rescued the decreased CRC metastasis induced by HOXA13 knockdown. Furthermore, Insulin-like growth factor 1 (IGF1), the ligand of IGF1R, upregulated HOXA13 expression through the PI3K/AKT/HIF1α pathway. Knockdown of HOXA13 decreased IGF1-mediated CRC metastasis. In addition, the combined treatment of ACLY inhibitor ETC-1002 and IGF1R inhibitor Linsitinib dramatically suppressed HOXA13-mediated CRC metastasis. In conclusion, HOXA13 is a prognostic biomarker in CRC patients. Targeting the IGF1-HOXA13-IGF1R positive feedback loop may provide a potential therapeutic strategy for the treatment of HOXA13-driven CRC metastasis.

Discovery of analogues of non-ß oxidizable long-chain dicarboxylic fatty acids as dual inhibitors of fatty acids and cholesterol synthesis: Efficacy of lead compound in hyperlipidemic hamsters reveals novel mechanism.

BACKGROUND AND AIMS: Cholesterol and triglycerides are risk factors for developing cardiovascular disease. Therefore, appropriate cells and assays are required to discover and develop dual cholesterol and fatty acid inhibitors. A predictive hyperlipidemic animal model is needed to evaluate mechanism of action of lead molecule for therapeutic indications. METHODS AND RESULTS: Primary hepatocytes from rat, hamster, rabbit, and humans were compared for suitability to screen compounds by de novo lipogenesis (DNL) using14C-acetate. Hyperlipidemic hamsters were used to evaluate efficacy and mode of action. In rat hepatocytes DNL assay, both the central moiety and carbon chain length influenced the potency of lipogenesis inhibition. In hyperlipidemic hamsters, ETC-1002 decreased plasma cholesterol and triglycerides by 41% and 49% at the 30 mg/kg dose. Concomitant decreases in non-esterified fatty acids (-34%) and increases in ketone bodies (20%) were associated with induction of hepatic CPT1-α. Reductions in proatherogenic VLDL-C and LDL-C (-71% and -64%) occurred partly through down-regulation of DGAT2 and up-regulation of LPL and PDK4. Activation of PLIN1 and PDK4 dampened adipogenesis and showed inverse correlation with adipose mass. Hepatic concentrations of cholesteryl ester and TG decreased by 67% and 64%, respectively. Body weight decreased with concomitant decreases in epididymal fat. Plasma and liver concentrations of ETC-1002 agreed with the observed dose-response efficacy. CONCLUSIONS: Taken together, ETC-1002 reduced proatherogenic lipoproteins, hepatic lipids and adipose tissues in hyperlipidemic hamsters via induction of LPL, CPT1-α, PDK4, and PLIN1, and downregulation of DGAT2. These characteristics may be useful in the treatment of fatty livers that causes non-alcoholic steatohepatitis.

Spectroscopic and biochemical characterization of metallo-ß-lactamase IMP-1 with dicarboxylic, sulfonyl, and thiol inhibitors.

In an effort to probe the biophysical mechanisms of inhibition for ten previously-reported inhibitors of metallo-ß-lactamases (MBL) with MBL IMP-1, equilibrium dialysis, metal analyses coupled with atomic absorption spectroscopy (AAS), native state mass spectrometry (native MS), and ultraviolet-visible spectrophotometry (UV-VIS) were used. 6-(1H-tetrazol-5-yl) picolinic acid (1T5PA), ANT431, D/l-captopril, thiorphan, and tiopronin were shown to form IMP-1/Zn(II)/inhibitor ternary complexes, while dipicolinic acid (DPA) and 4-(3-aminophenyl)pyridine-2,6-dicarboxylic acid (3AP-DPA) stripped some metal from the active site of IMP but also formed ternary complexes. DPA and 3AP-DPA stripped less metal from IMP-1 than from VIM-2 but stripped more metal from IMP-1 than from NDM-1. In contrast to a previous report, pterostilbene does not appear to bind to IMP-1 under our conditions. These results, along with previous studies, demonstrate similar mechanisms of inhibition toward different MBLs for different MBL inhibitors.

Bempedoic acid. Mechanism of action and pharmacokinetic and pharmacodynamic properties. / Ácido bempedoico. Mecanismo de acción y propiedades farmacocinéticas y farmacodinámicas.

Bempedoic acid acts by inhibiting adenosine triphosphate-citrate lyase (ACL) and consequently cholesterol biosynthesis, leading to increased expression of LDL receptors and increasing low-density lipoproteins (LDL-C) plasma clearence. It is a prodrug for oral administration with intracellular activation. It is activatedin liver cells and to a lesser extent in kidney cells, being absent in adipose tissue and muscle cells. Therefore, unlike statins, its potential myotoxic effect is very limited. It has recently been approved as a lipid-lowering drug in combination with diet, with statins, or with other lipid-lowering drugs in patients with hypercholesterolaemia, mixed dyslipidaemia, statin intolerance, or when these are contraindicated. The marketing of bempedoic acid implies, in clinical practice, having a new family of lipid-lowering drugs.

Bempedoic Acid for Heterozygous Familial Hypercholesterolemia: From Bench to Bedside.

Bempedoic acid is a first-in-class, oral, inhibitor of cholesterol biosynthesis that is approved for use in patients with atherosclerotic cardiovascular disease (ASCVD) and for primary prevention in individuals with heterozygous familial hypercholesterolemia (HeFH) by the United States Food and Drug Administration. Pooled data from the phase III clinical trials, CLEAR Harmony and CLEAR Wisdom, have demonstrated the safety and efficacy of bempedoic acid with regard to lowering of low-density lipoprotein cholesterol (LDL-C) in patients with HeFH as an adjunct or alternative to currently existing lipid-lowering therapies. CLEAR Outcomes is a cardiovascular outcomes trial that is currently underway that will provide additional insight as to where bempedoic acid will fit into treatment regimens among the non-statin lipid-lowering therapy options. Patients who might particularly benefit from bempedoic acid are those with HeFH and those unable to take adequate doses of statins or take any statin therapy altogether who need additional LDL-C lowering. In this review, we will discuss the profile of bempedoic acid from its design, development, and its place in therapy for the management of LDL-C for the purposes of ASCVD prevention.

SAR insights into TET2 catalytic domain inhibition: Synthesis of 2-Hydroxy-4-Methylene-pentanedicarboxylates.

The TET (Ten-Eleven Translocation) dioxygenase enzyme family comprising 3 members, TET1-3, play key roles in DNA demethylation. These processes regulate transcription programs that determine cell lineage, survival, proliferation, and differentiation. The impetus for our investigations described here is derived from the need to develop illuminating small molecule probes for TET enzymes with cellular activity and specificity. The studies were done so in the context of the importance of TET2 in the hematopoietic system and the preponderance of loss of function somatic TET2 mutations in myeloid diseases. We have identified that 2-hydroxy-4-methylene-pentanedicarboxylic acid 2a reversibly competes with the co-substrate α-KG in the TET2 catalytic domain and inhibits the dioxygenase activity with an IC50 = 11.0 ± 0.9 µM at 10 µM α-KG in a cell free system and binds in the TET2 catalytic domain with Kd = 0.3 ± 0.12 µM.