Structural and functional analysis of a bile salt hydrolase from the bison microbiome.

The bile salt hydrolases (BSHs) are significant constituents of animal microbiomes. An evolving appreciation of their roles in health and disease has established them targets of pharmacological inhibition. These bacterial enzymes belong to the N-terminal nucleophile superfamily and are best known to catalyze the deconjugation of glycine or taurine from bile salts to release bile acid substrates for transformation and or metabolism in the gastrointestinal tract. Here, we identify and describe the BSH from a common member of the Plains bison microbiome, Arthrobacter citreus (BSHAc). Steady-state kinetic analyses demonstrated that the BSHAc is a broad-spectrum hydrolase with a preference for glycine-conjugates and deoxycholic acid (DCA). Second order rate constants (kcat/KM) for BSHAc-catalyzed reactions of relevant bile salts - glyco- and tauro-conjugates of cholic acid and DCA - varied by ∼30-fold and measured between 1.4 x 105 and 4.3 x 106 M-1s-1. Interestingly, a pan-BSH inhibitor named AAA-10 acted as a slow irreversible inhibitor of BSHAc with a rate of inactivation (kinact) of ∼2 h-1 and a second order rate constant (kinact/KI) of ∼24 M-1s-1 for the process. Structural characterization of BSHAc reacted with AAA-10 showed covalent modification of the N-terminal cysteine nucleophile, providing molecular details for an enzyme-stabilized product formed from this mechanism-based inhibitor's α-fluoromethyl ketone warhead. Structural comparison of the BSHs and BSH:inhibitor complexes highlighted the plasticity of the steroid-binding site, including a flexible loop that is variable across well-studied BSHs.

Evolution, Structure, and Drug-Metabolising Activity of Mammalian Prenylcysteine Oxidases.

Prenylcysteine oxidases (PCYOXs) metabolize prenylated cysteines produced by protein degradation. They utilize oxygen as co-substrate to produce free cysteine, an aldehyde, and hydrogen peroxide through the unusual oxidation of a thioether bond. In this study, we explore the evolution, structure, and mechanism of the two mammalian PCYOXs. A gene duplication event in jawed vertebrates originated these two paralogs. Both enzymes are active on farnesyl- and geranylgeranylcysteine, but inactive on molecules with shorter prenyl groups. Kinetics experiments outline a mechanism where flavin reduction and re-oxidation occur rapidly without any detectable intermediates, with the overall reaction rate limited by product release. The experimentally determined three-dimensional structure of PCYOX1 reveals long and wide tunnels leading from the surface to the flavin. They allow the isoprene substrate to curl up within the protein and position its reactive cysteine group close to the flavin. A hydrophobic patch on the surface mediates membrane association, enabling direct substrate and product exchange with the lipid bilayer. Leveraging established knowledge on flavoenzyme inhibition, we designed sub-micromolar PCYOX inhibitors. Additionally, we discovered that PCYOXs bind and slowly degrade salisirab, an anti-RAS compound. This activity suggests potential and previously unknown roles of PCYOXs in drug metabolism.

Klebsiella pneumoniae carbapenemase variant 44 acquires ceftazidime-avibactam resistance by altering the conformation of active-site loops.

Klebsiella pneumoniae carbapenemase 2 (KPC-2) is an important source of drug resistance as it can hydrolyze and inactivate virtually all ß-lactam antibiotics. KPC-2 is potently inhibited by avibactam via formation of a reversible carbamyl linkage of the inhibitor with the catalytic serine of the enzyme. However, the use of avibactam in combination with ceftazidime (CAZ-AVI) has led to the emergence of CAZ-AVI-resistant variants of KPC-2 in clinical settings. One such variant, KPC-44, bears a 15 amino acid duplication in one of the active-site loops (270-loop). Here, we show that the KPC-44 variant exhibits higher catalytic efficiency in hydrolyzing ceftazidime, lower efficiency toward imipenem and meropenem, and a similar efficiency in hydrolyzing ampicillin, than the WT KPC-2 enzyme. In addition, the KPC-44 variant enzyme exhibits 12-fold lower AVI carbamylation efficiency than the KPC-2 enzyme. An X-ray crystal structure of KPC-44 showed that the 15 amino acid duplication results in an extended and partially disordered 270-loop and also changes the conformation of the adjacent 240-loop, which in turn has altered interactions with the active-site omega loop. Furthermore, a structure of KPC-44 with avibactam revealed that formation of the covalent complex results in further disorder in the 270-loop, suggesting that rearrangement of the 270-loop of KPC-44 facilitates AVI carbamylation. These results suggest that the duplication of 15 amino acids in the KPC-44 enzyme leads to resistance to CAZ-AVI by modulating the stability and conformation of the 270-, 240-, and omega-loops.

A novel aminopeptidase N/CD13 inhibitor selectively targets an endothelial form of CD13 after coupling to proteins.

Aminopeptidase N/CD13, a membrane-bound enzyme upregulated in tumor vasculature and involved in angiogenesis, can be used as a receptor for the targeted delivery of drugs to tumors through ligand-directed targeting approaches. We describe a novel peptide ligand (VGCARRYCS, called "G4") that recognizes CD13 with high affinity and selectivity. Enzymological and computational studies showed that G4 is a competitive inhibitor that binds to the catalytic pocket of CD13 through its N-terminal region. Fusing the peptide C-terminus to tumor necrosis factor-alpha (TNF) or coupling it to a biotin/avidin complex causes loss of binding and inhibitory activity against different forms of CD13, including natural or recombinant ectoenzyme and a membrane form expressed by HL60 promyelocytic leukemia cells (likely due to steric hindrance), but not binding to a membrane form of CD13 expressed by endothelial cells (ECs). Furthermore, G4-TNF systemically administered to tumor-bearing mice exerted anticancer effects through a CD13-targeting mechanism, indicating the presence of a CD13 form in tumor vessels with an accessible binding site. Biochemical studies showed that most CD13 molecules expressed on the surface of ECs are catalytically inactive. Other functional assays showed that these molecules can promote endothelial cell adhesion to plates coated with G4-avidin complexes, suggesting that the endothelial form of CD13 can exert catalytically independent biological functions. In conclusion, ECs express a catalytically inactive form of CD13 characterized by an accessible conformation that can be selectively targeted by G4-protein conjugates. This form of CD13 may represent a specific target receptor for ligand-directed targeted delivery of therapeutics to tumors.

The monodomain Kunitz protein EgKU-7 from the dog tapeworm Echinococcus granulosus is a high-affinity trypsin inhibitor with two interaction sites.

Typical Kunitz proteins (I2 family of the MEROPS database, Kunitz-A family) are metazoan competitive inhibitors of serine peptidases that form tight complexes of 1:1 stoichiometry, mimicking substrates. The cestode Echinococcus granulosus, the dog tapeworm causing cystic echinococcosis in humans and livestock, encodes an expanded family of monodomain Kunitz proteins, some of which are secreted to the dog host interface. The Kunitz protein EgKU-7 contains, in addition to the Kunitz domain with the anti-peptidase loop comprising a critical arginine, a C-terminal extension of ∼20 amino acids. Kinetic, electrophoretic, and mass spectrometry studies using EgKU-7, a C-terminally truncated variant, and a mutant in which the critical arginine was substituted by alanine, show that EgKU-7 is a tight inhibitor of bovine and canine trypsins with the unusual property of possessing two instead of one site of interaction with the peptidases. One site resides in the anti-peptidase loop and is partially hydrolyzed by bovine but not canine trypsins, suggesting specificity for the target enzymes. The other site is located in the C-terminal extension. This extension can be hydrolyzed in a particular arginine by cationic bovine and canine trypsins but not by anionic canine trypsin. This is the first time to our knowledge that a monodomain Kunitz-A protein is reported to have two interaction sites with its target. Considering that putative orthologs of EgKU-7 are present in other cestodes, our finding unveils a novel piece in the repertoire of peptidase-inhibitor interactions and adds new notes to the evolutionary host-parasite concerto.

Heart failure pharmacotherapy and cancer: pathways and pre-clinical/clinical evidence.

Heart failure (HF) patients have a significantly higher risk of new-onset cancer and cancer-associated mortality, compared to subjects free of HF. While both the prevention and treatment of new-onset HF in patients with cancer have been investigated extensively, less is known about the prevention and treatment of new-onset cancer in patients with HF, and whether and how guideline-directed medical therapy (GDMT) for HF should be modified when cancer is diagnosed in HF patients. The purpose of this review is to elaborate and discuss the effects of pillar HF pharmacotherapies, as well as digoxin and diuretics on cancer, and to identify areas for further research and novel therapeutic strategies. To this end, in this review, (i) proposed effects and mechanisms of action of guideline-directed HF drugs on cancer derived from pre-clinical data will be described, (ii) the evidence from both observational studies and randomized controlled trials on the effects of guideline-directed medical therapy on cancer incidence and cancer-related outcomes, as synthetized by meta-analyses will be reviewed, and (iii) considerations for future pre-clinical and clinical investigations will be provided.

Meta-analysis of ACE inhibitor-induced angioedema identifies novel risk locus.

BACKGROUND: Angioedema is a rare but potentially life-threatening adverse drug reaction in patients receiving angiotensin-converting enzyme inhibitors (ACEis). Research suggests that susceptibility to ACEi-induced angioedema (ACEi-AE) involves both genetic and nongenetic risk factors. Genome- and exome-wide studies of ACEi-AE have identified the first genetic risk loci. However, understanding of the underlying pathophysiology remains limited. OBJECTIVE: We sought to identify further genetic factors of ACEi-AE to eventually gain a deeper understanding of its pathophysiology. METHODS: By combining data from 8 cohorts, a genome-wide association study meta-analysis was performed in more than 1000 European patients with ACEi-AE. Secondary bioinformatic analyses were conducted to fine-map associated loci, identify relevant genes and pathways, and assess the genetic overlap between ACEi-AE and other traits. Finally, an exploratory cross-ancestry analysis was performed to assess shared genetic factors in European and African-American patients with ACEi-AE. RESULTS: Three genome-wide significant risk loci were identified. One of these, located on chromosome 20q11.22, has not been implicated previously in ACEi-AE. Integrative secondary analyses highlighted previously reported genes (BDKRB2 [bradykinin receptor B2] and F5 [coagulation factor 5]) as well as biologically plausible novel candidate genes (PROCR [protein C receptor] and EDEM2 [endoplasmic reticulum degradation enhancing alpha-mannosidase like protein 2]). Lead variants at the risk loci were found with similar effect sizes and directions in an African-American cohort. CONCLUSIONS: The present results contributed to a deeper understanding of the pathophysiology of ACEi-AE by (1) providing further evidence for the involvement of bradykinin signaling and coagulation pathways and (2) suggesting, for the first time, the involvement of the fibrinolysis pathway in this adverse drug reaction. An exploratory cross-ancestry comparison implicated the relevance of the associated risk loci across diverse ancestries.

Crystal structure of histone deacetylase 6 complexed with (R)-lipoic acid, an essential cofactor in central carbon metabolism.

The enzyme cofactor (R)-lipoic acid plays a critical role in central carbon metabolism due to its catalytic function in the generation of acetyl-CoA, which links glycolysis with the tricarboxylic acid cycle. This cofactor is also essential for the generation of succinyl CoA within the tricarboxylic acid cycle. However, the biological functions of (R)-lipoic acid extend beyond metabolism owing to its facile redox chemistry. Most recently, the reduced form of (R)-lipoic acid, (R)-dihydrolipoic acid, has been shown to inhibit histone deacetylases (HDACs) with selectivity for the inhibition of HDAC6. Here, we report the 2.4 Å-resolution X-ray crystal structure of the complex between (R)-dihydrolipoic acid and HDAC6 catalytic domain 2 from Danio rerio, and we report a dissociation constant (KD) of 350 nM for this complex as determined by isothermal titration calorimetry. The crystal structure illuminates key affinity determinants in the enzyme active site, including thiolate-Zn2+ coordination and S-π interactions in the F583-F643 aromatic crevice. This study provides the first visualization of the connection between HDAC function and the biological response to oxidative stress: the dithiol moiety of (R)-dihydrolipoic acid can serve as a redox-regulated pharmacophore capable of simultaneously targeting the catalytic Zn2+ ion and the aromatic crevice in the active site of HDAC6.

The small molecule inhibitor NAV-2729 has a complex target profile including multiple ADP-ribosylation factor regulatory proteins.

The ADP-ribosylation factor (Arf) GTPases and their regulatory proteins are implicated in cancer progression. NAV-2729 was previously identified as a specific inhibitor of Arf6 that reduced progression of uveal melanoma in an orthotopic xenograft. Here, our goal was to assess the inhibitory effects of NAV-2729 on the proliferation of additional cell types. We found NAV-2729 inhibited proliferation of multiple cell lines, but Arf6 expression did not correlate with NAV-2729 sensitivity, and knockdown of Arf6 affected neither cell viability nor sensitivity to NAV-2729. Furthermore, binding to native Arf6 was not detected; however, we determined that NAV-2729 inhibited both Arf exchange factors and Arf GTPase-activating proteins. ASAP1, a GTPase-activating protein linked to cancer progression, was further investigated. We demonstrated that NAV-2729 bound to the PH domain of ASAP1 and changed ASAP1 cellular distribution. However, ASAP1 knockdown did not fully recapitulate the cytoskeletal effects of NAV-2729 nor affect cell proliferation. Finally, our screens identified 48 other possible targets of NAV-2729. These results illustrate the complexities of defining targets of small molecules and identify NAV-2729 as a model PH domain-binding inhibitor.

5-Formyltetrahydrofolate promotes conformational remodeling in a methylenetetrahydrofolate reductase active site and inhibits its activity.

The flavoprotein methylenetetrahydrofolate reductase (MTHFR) catalyzes the reduction of N5, N10-methylenetetrahydrofolate (CH2-H4folate) to N5-methyltetrahydrofolate (CH3-H4folate), committing a methyl group from the folate cycle to the methionine one. This committed step is the sum of multiple ping-pong electron transfers involving multiple substrates, intermediates, and products all sharing the same active site. Insight into folate substrate binding is needed to better understand this multifunctional active site. Here, we performed activity assays with Thermus thermophilus MTHFR (tMTHFR), which showed pH-dependent inhibition by the substrate analog, N5-formyltetrahydrofolate (CHO-H4folate). Our crystal structure of a tMTHFR•CHO-H4folate complex revealed a unique folate-binding mode; tMTHFR subtly rearranges its active site to form a distinct folate-binding environment. Formation of a novel binding pocket for the CHO-H4folate p-aminobenzoic acid moiety directly affects how bent the folate ligand is and its accommodation in the active site. Comparative analysis of the available active (FAD- and folate-bound) MTHFR complex structures reveals that CHO-H4folate is accommodated in the active site in a conformation that would not support hydride transfer, but rather in a conformation that potentially reports on a different step in the reaction mechanism after this committed step, such as CH2-H4folate ring-opening. This active site remodeling provides insights into the functional relevance of the differential folate-binding modes and their potential roles in the catalytic cycle. The conformational flexibility displayed by tMTHFR demonstrates how a shared active site can use a few amino acid residues in lieu of extra domains to accommodate chemically distinct moieties and functionalities.

Identification of novel plant cysteine oxidase inhibitors from a yeast chemical genetic screen.

Hypoxic responses in plants involve Plant Cysteine Oxidases (PCOs). They catalyze the N-terminal cysteine oxidation of Ethylene Response Factors VII (ERF-VII) in an oxygen-dependent manner, leading to their degradation via the cysteine N-degron pathway (Cys-NDP) in normoxia. In hypoxia, PCO activity drops, leading to the stabilization of ERF-VIIs and subsequent hypoxic gene upregulation. Thus far, no chemicals have been described to specifically inhibit PCO enzymes. In this work, we devised an in vivo pipeline to discover Cys-NDP effector molecules. Budding yeast expressing AtPCO4 and plant-based ERF-VII reporters was deployed to screen a library of natural-like chemical scaffolds and was further combined with an Arabidopsis Cys-NDP reporter line. This strategy allowed us to identify three PCO inhibitors, two of which were shown to affect PCO activity in vitro. Application of these molecules to Arabidopsis seedlings led to an increase in ERF-VII stability, induction of anaerobic gene expression, and improvement of tolerance to anoxia. By combining a high-throughput heterologous platform and the plant model Arabidopsis, our synthetic pipeline provides a versatile system to study how the Cys-NDP is modulated. Its first application here led to the discovery of at least two hypoxia-mimicking molecules with the potential to impact plant tolerance to low oxygen stress.

Chlorotoxin binds to both matrix metalloproteinase 2 and neuropilin 1.

Chlorotoxin (CTX), a scorpion venom-derived 36-residue miniprotein, binds to and is taken up selectively by glioblastoma cells. Previous studies provided controversial results concerning target protein(s) of CTX. These included CLC3 chloride channel, matrix metalloproteinase 2 (MMP-2), regulators of MMP-2, annexin A2, and neuropilin 1 (NRP1). The present study aimed at clarifying which of the proposed binding partners can really interact with CTX using biochemical methods and recombinant proteins. For this purpose, we established two new binding assays based on anchoring the tested proteins to microbeads and quantifying the binding of CTX by flow cytometry. Screening of His-tagged proteins anchored to cobalt-coated beads indicated strong interaction of CTX with MMP-2 and NRP1, whereas binding to annexin A2 was not confirmed. Similar results were obtained with fluorophore-labeled CTX and CTX-displaying phages. Affinity of CTX to MMP-2 and NRP1 was assessed by the "immunoglobulin-coated bead" test, in which the proteins were anchored to beads by specific antibodies. This assay yielded highly reproducible data using both direct titration and displacement approach. The affinities of labeled and unlabeled CTX appeared to be similar for both MMP-2 and NRP1 with estimated KD values of 0.5 to 0.7 µM. Contrary to previous reports, we found that CTX does not inhibit the activity of MMP-2 and that CTX not only with free carboxyl end but also with carboxamide terminal end binds to NRP1. We conclude that the presented robust assays could also be applied for affinity-improving studies of CTX to its genuine targets using phage display libraries.

Effects of Dipeptidyl Peptidase-4 Inhibitor and Angiotensin-Converting Enzyme Inhibitor on Experimental Diabetic Kidney Disease.

Diabetic kidney disease (DKD) is the leading cause of end-stage kidney disease in the United States and worldwide. Proteinuria is a major marker of the severity of injury. Dipeptidyl peptidase-4 inhibitor (DPP-4I) increases incretin-related insulin production and is, therefore, used to treat diabetes. We investigated whether DPP4I could have direct effect on kidney independent of its hypoglycemic activity. We, therefore, tested the effects of DPP4I with or without angiotensin-converting enzyme inhibitor (ACEI) on the progression of diabetic nephropathy and albuminuria in a murine model of DKD. eNOS-/-db/db mice were randomized to the following groups at age 10 weeks and treated until sacrifice: baseline (sacrificed at week 10), untreated control, ACEI, DPP4I, and combination of DPP4I and ACEI (Combo, sacrificed at week 18). Systemic parameters and urine albumin-creatinine ratio were assessed at baseline, weeks 14, and 18. Kidney morphology, glomerular filtration rate (GFR), WT-1, a marker for differentiated podocytes, podoplanin, a marker of foot process integrity, glomerular collagen IV, and alpha-smooth muscle actin were assessed at the end of the study. All mice had hyperglycemia and proteinuria at study entry at week 10. Untreated control mice had increased albuminuria, progression of glomerular injury, and reduced GFR at week 18 compared with baseline. DPP4I alone reduced blood glucose and kidney DPP-4 activity but failed to protect against kidney injury compared with untreated control. ACEI alone and combination groups showed significantly reduced albuminuria and glomerular injury, and maintained GFR and WT-1+ cells. Only the combination group had significantly less glomerular collagen IV deposition and more podoplanin preservation than the untreated control. DPP-4I alone does not decrease the progression of kidney injury in the eNOS-/-db/db mouse model, suggesting that targeting only hyperglycemia is not an optimal treatment strategy for DKD. Combined DPP-4I with ACEI added more benefit to reducing the glomerular matrix.

Evaluation of the stopping angiotensin converting enzyme inhibitor compared to angiotensin receptor blocker (STOP ACEi trial) in advanced and progressive chronic kidney disease.

In the STOP-ACEi trial, the outcome was similar whether or not renin-angiotensin system inhibitors (RASi) were discontinued. We now investigate whether the effect of withdrawing angiotensin converting enzyme inhibitors (ACEi) or angiotensin-receptor blockers (ARBs) differed. In this open label trial patients with estimated glomerular filtration rates (eGFR) under 30ml/min per 1.73 m2 and progressive chronic kidney disease (CKD) were randomized to stop or continue RASi. The primary outcome was eGFR at three years. The composite of kidney failure, over 50% fall in eGFR, or kidney replacement therapy (KRT) was also assessed. Of patients randomized, 99 stopped and 123 patients continued ACEi while 104 stopped and 77 continued ARB at baseline. At three years, the eGFR was similar whether or not patients were withdrawn from ACEi or from ARB. Kidney failure or initiation of KRT occurred in 65% of those stopping and 54% continuing ACEi (hazard ratio if stopped, 1.52; 95% Confidence Interval, 1.07 to 2.16) and in 60% on an ARB regardless of randomized group (hazard ratio if stopped, 1.23; 0.83 to 1.81). Kidney failure/Initiation of KRT with over 50% decline in eGFR occurred in 71% of those stopping and 59% continuing ACEi (relative risk if stopped, 1.19; 95% CI, 1.00 to 1.41) and in 65% stopping and 69% continuing ARB (relative risk if stopped, 0.96; 0.79 to 1.16). Thus, neither discontinuing ACEi nor ARB slowed the rate of decline in eGFR. Although discontinuation of ACEi appeared to have more unfavorable effects on kidney outcomes than stopping ARB, the trial was neither designed nor powered to show differences between agents.

Systematic Review Examining the Association Between Angiotensin Converting Enzyme Inhibitor or Angiotensin Receptor Blocker Prescription and Abdominal Aortic Aneurysm Growth and Events.

OBJECTIVE: Whether angiotensin II blockade is an effective medical treatment for abdominal aortic aneurysms (AAAs) has not been established. This systematic review and meta-analysis aimed to determine the association between angiotensin converting enzyme inhibitor (ACEi) or angiotensin receptor blocker (ARB) prescription and AAA growth and events. DATA SOURCES: MEDLINE, Embase, Scopus, Web of Science, and the Cochrane Library databases were searched from their inception to 4 January 2024, with no language restrictions. REVIEW METHODS: The five databases were searched for randomised controlled trials (RCTs) and observational studies reporting the association between ACEi or ARB prescription and AAA growth, repair, or rupture. The primary outcome was AAA growth, with secondary outcomes of AAA rupture, AAA repair, and AAA related events (rupture and repair combined). Risk of bias was assessed using the Risk of Bias 2 tool for RCTs and with a modified Newcastle-Ottawa scale for observational studies. Certainty of evidence was assessed using the Grading of Recommendations, Assessment, Development, and Evaluation (GRADE). Random effects models were used for meta-analyses. RESULTS: Eleven studies (two RCTs, eight observational studies, and one meta-analysis of individual patient data from seven populations) involving 58 022 patients were included. ACEi prescription was not associated with a statistically significant reduction in AAA growth (standard mean difference 0.01 mm/year, 95% confidence interval [CI] -0.26 - 0.28; p = .93; I2 = 98%) or AAA repair (odds ratio [OR] 0.73, 95% CI 0.50 - 1.09; p = .65; I2 = 61%), but was associated with a statistically significantly lower risk of AAA rupture (OR 0.87, 95% CI 0.81 - 0.93; p < .001; I2 = 26%) and AAA related events (OR 0.82, 95% CI 0.72 - 0.95; p = .006; I2 = 80%). ARB prescription was not associated with significantly reduced AAA growth or a lower risk of AAA related events. The two RCTs had a low risk of bias, with one observational study having low, seven moderate, and one high risk of bias. All of the findings had a very low certainty of evidence based on the GRADE analysis. CONCLUSION: There was no association between ACEi or ARB prescription and AAA growth, but ACEi prescription was associated with a reduced risk of AAA rupture and AAA related events with very low certainty of evidence.

Sacubitril/valsartan compared to equivalent/sub-equivalent dose angiotensin receptor blocker or angiotensin-converting enzyme inhibitor in heart failure with reduced ejection fraction: a meta-analysis of randomized trials.

PURPOSE: The objective of this meta-analysis is to determine how sacubitril/valsartan (SV) compares to equivalent and sub-equivalent angiotensin receptor blockers (ARB) or angiotensin-converting enzyme inhibitors (ACEI) in patients with heart failure with reduced ejection fraction (HFrEF). METHODS: The databases of PubMed and EMBASE were used to identify those randomized controlled trials which compared SV to ARB/ACEI in patients with HFrEF. Only those trials that reported outcomes regarding total mortality, cardiovascular mortality, and worsening heart failure were considered. Meta-analysis was performed separately in those patients receiving equivalent doses of ARB/ACEI and those receiving sub-equivalent doses. Equivalent doses were SV 97/103 = valsartan 160 mg twice daily = enalapril 20 mg twice daily = ramipril 5 mg twice daily. Meta-analyses were performed using Review Manager 5.4. RESULTS: Twelve randomized trials were identified involving 17,484 patients: 11,291 in the sub-equivalent group (8 trials) and 6193 in the equivalent group (4 trials). Meta-analyses showed there were no statistical differences regarding the outcomes of total mortality, cardiovascular mortality, and worsening heart failure in the equivalent dosing group. However, SV reduced total mortality (risk ratio (RR) = 0.85, 95% confidence interval (CI) = 0.78-0.93, p < 0.001), cardiovascular mortality (RR = 0.81, 95% CI = 0.73-0.90, p ≤ 0.001) and worsening heart failure (RR = 0.77, 95% CI = 0.64-0.92, p = 0.005) in the sub-equivalent group. CONCLUSION: When compared to equivalent doses of ARB/ACEI, SV is not superior in reducing mortality and worsening heart failure. SV is superior when compared to sub-equivalent doses of ACEI.

Investigation of cardiorenal outcomes and incidence of genitourinary tract infection after combined SGLT2 inhibitor and ACEI/ARB use in patients with chronic kidney disease stages 3-5: A real-world retrospective cohort study in Taiwan.

Background: Sodium‒glucose cotransporter-2 (SGLT2) inhibitors offer glycaemic and cardiorenal benefits in the early stage of chronic kidney disease (CKD). However, the use of SGLT2 inhibitors may increase the risk of genitourinary tract infection (GUTI). Angiotensin-converting enzyme inhibitors (ACEIs) and angiotensin receptor blockers (ARBs) may also cause deterioration of kidney function. The long-term follow-up of cardiorenal outcomes and GUTI incidence in patients with advanced CKD receiving SGLT2 inhibitors combined with ACEIs/ARBs should be further investigated. Methods: We analysed data from 5,503 patients in Taiwan's Taipei Medical University Research Database (2016-2020) who were part of a pre-end-stage renal disease (ESRD) program (CKD stages 3-5) and received ACEIs/ARBs. SGLT2 inhibitor users were matched 1:4 with nonusers on the basis of sex, CKD, and program entry duration. Results: The final cohort included 205 SGLT2 inhibitor users and 820 nonusers. SGLT2 inhibitor users experienced a significant reduction in ESRD/dialysis risk (aHR = 0.35, 95% CI = 0.190.67), and SGLT2 inhibitor use was not significantly associated with acute kidney injury or acute kidney disease risk. Among SGLT2 inhibitor users, those with a history of cardiovascular disease (CVD) had greater CVD rates. Conversely, those without a CVD history had lower rates of congestive heart failure, arrhythmia, acute pulmonary oedema, and acute myocardial infarction, although the differences were not statistically significant. Notably, SGLT2 inhibitor usage was associated with a greater GUTI incidence (aHR = 1.78, 95% CI = 1.122.84) shortly after initiation, irrespective of prior GUTI history status. Conclusion: Among patients with CKD stages 3-5, SGLT2 inhibitor use was linked to increased GUTI incidence, but it also significantly reduced the ESRD/dialysis risk without an episodic AKI or AKD risk. Clinical physicians should consider a personalized medicine approach by balancing GUTI episodes and cardiorenal outcomes for advanced CKD patients receiving SGLT2 inhibitors.

Timing of prescription of angiotensin-converting enzyme inhibitors/angiotensin receptor blockers in patients hospitalized for acute heart failure with reduced/mildly reduced ejection fraction: a retrospective analysis.

Although angiotensin-converting enzyme inhibitors (ACEis) and angiotensin II receptor blockers (ARBs) play critical roles in the treatment of heart failure with reduced or mildly reduced ejection fraction (HFrEF/HFmrEF; left-ventricular ejection fraction ≤ 50%), the ideal timing for initiation in patients with acute heart failure (AHF) is unclear. We sought to clarify the timing and safety of ACEi/ARB prescription relative to hemodynamic stabilization (pre or post) in patients hospitalized with acute HFrEF/HFmrEF. This was a retrospective, observational analysis of electronic data of patients hospitalized for AHF at 17 Japanese hospitals. Among 9107 patients hospitalized with AHF, 2648 had HFrEF/HFmrEF, and 83.0% met the hemodynamic stabilization criteria within 10 days of admission. During hospitalization, 63.5% of patients with HFrEF/HFmrEF were prescribed an ACEi/ARB, 79.4% of which were prescribed pre-stabilization. In a multivariable analysis, patients treated with an ACEi/ARB pre-stabilization were more likely to have comorbid hypertension, diabetes mellitus, or ischemic heart disease. ACEi/ARB prescription timing was not associated with adverse events, including hypotension and renal impairment, and early prescription was associated with a lower incidence of subsequent worsening of HF. In clinical practice, more hospitalized patients with AHF received an ACEi/ARB before compared with after hemodynamic stabilization, and no safety concerns were observed. Moreover, early prescription may be associated with a lower incidence of worsening HF.

Prevention of anthracycline and trastuzumab-induced decline in left ventricular ejection fraction with angiotensin-converting enzyme inhibitors or angiotensin receptor blocker: a narrative systematic review of randomised controlled trials.

Cancer therapy-related cardiac dysfunction (CTRCD) is a complication of selected cancer therapy agents associated with decline in left ventricular ejection fraction (LVEF). Angiotensin-converting enzyme inhibitors (ACEIs) and angiotensin receptor blockers (ARBs) have established benefits in heart failure with reduced ejection fraction, but their efficacy for preventing CTRCD remains controversial. This narrative systematic review assessed the efficacy and safety of ACEI/ARB in the prevention of cancer therapy LVEF decline. We systematically searched PubMed, Embase and Cochrane from January 1980 to June 2022. Studies of interest were randomised controlled trials of patients with normal LVEF and active malignancy receiving cancer therapy, randomised to receive either an ACEI or ARB compared with a control group. The outcome was the change in LVEF from baseline to the end of the follow-up period. Death, clinical heart failure and adverse drug reactions were recorded. A total of 3731 search records were screened and 12 studies were included, comprising a total of 1645 participants. Nine studies assessed the prevention of anthracycline-induced LVEF decline, of which five showed a beneficial effect (1%-14% higher LVEF in treated groups), whereas four studies showed no effect. Three studies assessed the prevention of trastuzumab-induced LVEF decline, of which one showed a beneficial effect (4% higher LVEF) in a subset of participants. There are mixed data regarding the efficacy of ACEI/ARB in preventing the LVEF decline in patients undergoing anthracycline or trastuzumab therapy, with evidence suggesting no clinically meaningful benefit observed in recent studies.

Peripheral (E)-2-[(4-hydroxybenzylidene)-3,4-dihydronaphthalen-1(2H)-one)]-coordinated phthalocyanines with improved enzyme inhibition properties and photophysicochemical behaviors.

In this study, (E)-4-{4-[(1-oxo-3,4-dihydronaphthalen-2(1H)-ylidene)methyl]phenoxy}phthalonitrile (4) and its phthalocyanine derivatives (5-8) were synthesized for the first time. Aggregation behaviors of the novel soluble phthalocyanines in organic solvents were investigated. In addition, the efficiency of 1O2 production of (5) and ZnPc (6) was investigated. The singlet oxygen quantum yields (ΦΔ) for 2HPc (5) and ZnPc (6) were found to be 0.58 and 0.83, respectively. Additionally, novel phthalocyanines (5-8) were investigated for their ability to inhibit enzymes. They exhibited a highly potent inhibition effect on human carbonic anhydrase I and II (hCA I and II) and α-glycosidase (α-Gly) enzymes. Ki values are in the range of 2.60 ± 9.87 to 11.53 ± 6.92 µM, 3.35 ± 0.53 to 15.47 ± 1.20 µM, and 28.60 ± 4.82 to 40.58 ± 7.37 nM, respectively. The calculations of the studied molecule at the B3LYP, HF, and M062X levels in the 6-31G basis sets were made using the Gaussian package program. Afterward, the interactions occurring in the docking calculation against a protein that is the crystal structure of hCA I (PDB ID: 2CAB), the crystal structure of hCA II (PDB ID: 5AML), and the crystal structure of α-Gly (PDB ID: 1R47), were examined. Following that, Protein-Ligand Interaction Profiler (PLIP) analysis was used to look at the interactions that occurred during the docking calculation in further detail.