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Effects of anticalcifying and antifibrobrotic drugs on pre-established atherosclerosis in the rabbit.

The effects of the anticalcifying drug, ethane-hydroxydiphosphonate (EHDP) and the inhibitors of collagen biosynthesis, colchicine, penicillamine and azetidine were studied in the rabbit with pre-established atherosclerosis. The drugs were administered with a cholesterol-free diet (regression diet) for 8 weeks following the induction of atherosclerosis by feeding a hypercholesterolemic diet containing 2% cholesterol and 8% peanut oil for 8 weeks. The extent and severity of aortic atherosclerosis, as revealed by the morphological and biochemical findings, increased significantly during the regression period. In rabbits treated with EHDP (5 mg/kg/day) the aorta had fewer gross lesions and contained significantly less cholesterol, collagen and elastin than did the aorta of the rabbits fed the regression diet alone. These changes were associated with a significant reduction in aortic calcium caused by EHDP. The aortic content of cholesterol, collagen and elastin in the EHDP-treated rabbits, although less than that of the rabbits fed the regression diet alone, was about the same as that of the rabbits fed a high cholesterol diet for 8 weeks. Both colchicine (0.2 mg/kg/day) and penicillamine (100 mg/kg/day) had a selective action on the induced plaques in that they suppressed the fibrous proliferation in the lesions without preventing lipid and calcium accumulation in the lesions. Neither colchicine nor penicillamine reduced the extent of aortic atherosclerosis as determined by gross examination of the vessel. Azetidine had no significant effect on the pre-established atherosclerotic lesions. The lipid, fibrous protein and calcium content of the aorta of the azetidine-treated animals was not significantly different from that of the untreated animals. The biochemical findings in the aorta were consistent with the microscopic changes.

Animals

Production, isolation, and properties of azetomycins.

Streptomyces antibioticus synthesizes five actinomycins that differ in the "proline site" of the molecule. When cultured in the presence of azetidine-2-carboxylic acid (AzC), antibiotic synthesis was stimulated 40 to 50%, synthesis of actinomycin IV was inhibited, and one or both prolines were replaced by AzC. AzC incorporation could not be reversed by concomitant supplementation with proline or sarcosine, and only pipecolic acid affected a minor reversal of AzC incorporation. AzC-containing actinomycins were isolated and designated azet-I and azet-II; a third unresolved component or mixture was called azet-III. The molar ratio of AzC to proline was: azet-I, 1:1; azet-II, 2:0. Azet-III was equivocal. These azetidine actinomycins (azetomycins) were found to be potently inhibitory to the growth of selected gram-positive but not as potent to the growth of gram-negative organisms. The relative inhibitory affect against growth and ribonucleic acid synthesis in Bacillus subtilis was: actinomycin IV =/> azet-I > azet-II >>> azet-III. Protein synthesis was affected similarly; however, kinetic studies with B. subtilis revealed that ribonucleic acid synthesis was inhibited rapidly followed by an inhibition of protein synthesis. At concentrations less than 1 mug/ml, deoxyribonucleic acid synthesis was stimulated by these actinomycins.

Amino Acids

Regulation of herpesvirus macromolecular synthesis: sequential transition of polypeptide synthesis requires functional viral polypeptides.

It was previously shown that virus-specific polypeptides made in HEp-2 cells infected with herpes simplex 1 form three groups designated alpha, beta, and gamma whose synthesis is coordinately regulated and sequentially ordered. This report shows that one or more functional alpha polypeptides are necessary to turn on the synthesis of beta and gamma groups, and conversely, one or more polypeptides in the latter groups turn off the synthesis of alpha polypeptides. Specifically, infected cells maintained in medium containing either canavanine, an analogue of arginine, or azetidine-2-carboxylic acid an analogue of proline and hydroxyproline, synthesized alpha polypeptide at rates comparable to maximal rates in untreated infected cells but did not undergo the normal transition to beta and gamma polypeptide synthesis. The transition to gamma polypeptide synthesis and shut-off of synthesis of earlier polypeptide groups proceeded normally if addition of canavanine was delayed until at least 4-5 hr after infection. Addition of canavanine after the onset of beta and gamma polypeptide synthesis, i.e., between 2 and 3.5 hr after infection, resulted in sustained, simultaneous synthesis of all three polypeptide groups, a phenomenon not seen in untreated infected cells. Canavanine-treated infected cells, synthesizing alpha polypeptides, recovered the capacity to make beta and gamma polypeptides after removal of the analogue, but only after a 1-to 2-hr delay compared with infected untreated cells. The data indicate that the on and off controls inherent in the cascade regulation of viral polypeptide synthesis are mediated by one or more polypeptides in each group at transcriptional or post-transcriptional levels.

Azetidinecarboxylic Acid

Analysis of intracellular feline leukemia virus proteins II. Generation of feline leukemia virus structural proteins from precursor polypeptides.

The synthesis and processing of feline leukemia virus (FeLV) polypeptides were studied in a chronically infected feline thymus tumor cell line, F-422, which produces the Rickard strain of FeLV. Immune precipitation with antiserum to FeLV p30 and subsequent sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE) were used to isolate intracellular FeLV p30 and possible precursor polypeptides. SDS-PAGE of immune precipitates from cells pulse-labeled for 2.5 min with [35S]methionin revealed the presence of a 60,000-dalton precursor polypeptide (Pp60) as well as a 30,000-dalton polypeptide. When cells were grown in the presence of the proline analogue L-azetidine-2-carboxylic acid, a 70,000-dalton precursor polypeptide (Pp70) was found in addition to Pp60 after a 2.5-min pulse. The cleavage of Pp60 could be partially inhibited by the general protease inhibitor phenyl methyl sulfonyl fluoride (PMSF). This partial inhibition was found to occur only if PMSF was present during pulse-labeling. Intracellular Pp70 and Pp60 and FeLV virion p70, p30, p15, p11, and p10 were subjected to tryptic peptide analysis. The results of this tryptic peptide analysis demonstrated that intracellular Pp70 and virion p70 were identical and that both contained the tryptic peptides of FeLV p30, p15, p11, and p10. Pp60 contained the tryptic peptides of FeLV P30, P15, and P10, but lacked the tryptic peptides of P11. The results of pactamycin gene ordering experiments indicated that the small structural proteins of FeLV are ordered p11-p15-p10-p30. The data indicate that the small structural proteins of FeLV are synthesized as part of a 70,000-dalton precursor. A cleavage scheme for the generation of FeLV p70, p30, p15, p11, and p10 from precursor polypeptides is proposed.

Azetidinecarboxylic Acid

Efficacy and safety of JAK inhibitors in Behçet syndrome: systematic literature review.

OBJECTIVES: Given the active role of the JAK signaling pathway and the multifactorial immune mediators observed in Behçet syndrome (BS), JAK inhibitors (JAKi) may be promising agents. In this systematic literature review (SLR), we aim to evaluate the efficacy and safety of JAKi in BS. METHODS: A systematic literature search was conducted in Embase, PubMed, and the Cochrane Library to identify all reports on the efficacy and safety of JAKi in patients with BS. The SLR protocol was registered with the International Prospective Registry of Systematic Reviews (CRD420251000172). We additionally presented our patient with gastrointestinal involvement treated with upadacitinib. RESULTS: Among the 92 patients (48 men, mean (SD) age 38.5 (13.5) years), 46 used tofacitinib, 31 used baricitinib, and 15 used upadacitinib. All but 1 patient had used at least one previous conventional immunosuppressive, and 57.6% were refractory to at least one prior tumor necrosis factor inhibitor. JAKi were used in combination with conventional immunosuppressive and/or glucocorticoids in 90.6% of the patients. The primary indication for JAKi initiation was gastrointestinal involvement in 46 (50%) patients including our patient, vascular involvement in 22 (23.9%), uveitis in 19 (20.6%), and mucocutaneous and/or articular involvement in 5 (5.6%) patients. The remission rates for overall, gastrointestinal, vascular, and eye involvement were 85.9%, 82.6%, 90.9%, and 84.2%. Serious adverse events were observed in 5.4% of the patients. No thrombotic events were reported. CONCLUSION: This SLR showed that JAKi may be effective in refractory BS patients with a favorable safety profile.

Humans

Efficacy and safety of Janus kinase inhibitors in Behçet's disease: A systematic literature review.

INTRODUCTION: Behçet's disease e (BD) is a chronic, relapsing, multisystem inflammatory disorder that if not successfully treated can lead to severe, organ or life-threatening complications. Despite treatment with glucocorticoids, immunosuppressants, and tumor necrosis factor (TNF) inhibitors, some patients still have refractory disease that mandates additional therapeutic options. The pathogenesis of BD involves dysregulated innate and adaptive immune responses with multiple cytokines signaling through the Janus kinase (JAK)-signal transducer and activator of transcription (STAT) pathway. By targeting multiple inflammatory pathways, JAK inhibitors have emerged as a promising therapeutic option. However, current evidence remains limited and heterogeneous. Therefore, we conducted this systematic review to evaluate their efficacy and safety in BD. METHODS: We conducted a systematic literature review in accordance with PRISMA 2020 guidelines (PROSPERO registration: CRD420261381955). PubMed/MEDLINE, Embase, Scopus, and Web of Science were searched from inception to March 2026. Original clinical studies evaluating Janus kinase (JAK) inhibitors in BD were included. Two reviewers independently performed study selection, data extraction, and quality assessment using Joanna Briggs Institute tools. Due to heterogeneity, results were synthesized narratively, focusing on efficacy and safety outcomes. RESULTS: Seventeen studies (99 patients) were included, predominantly case reports and small observational cohorts with overall high methodological quality. All evaluated tofacitinib, baricitinib, or upadacitinib, with no data on other JAK inhibitors. Patients were highly treatment-refractory, with prior failure of conventional and biologic therapies. Upadacitinib was the most frequently studied agent and demonstrated an overall response rate of 85.2% and complete remission in 59.3% in a multi-center study. Efficacy was observed across multiple domains, with the most consistent responses in intestinal disease, including clinical and endoscopic remission, alongside frequent glucocorticoid-sparing effects. Safety findings were consistent with known JAK inhibitor safety profiles, with mainly mild to moderate infections and manageable laboratory abnormalities, and no clear signal for increased thrombotic events, although follow-up was limited. CONCLUSION: JAK inhibitors demonstrate promising efficacy in BD, particularly in refractory and multisystem disease. The most consistent evidence of efficacy was observed in gastrointestinal involvement, whereas data for other disease domains remain limited. Their safety profile appears consistent with existing data, although further follow up and validation is required. High-quality randomized controlled studies are an imminent need to study the potential role of JAK inhibitors in BD.

Humans

Efficacy of Janus kinase inhibitor combined with phototherapy in non-segmental vitiligo: systematic review and meta-analysis.

BACKGROUND: Vitiligo is a chronic autoimmune disease causing skin depigmentation and psychosocial issues. Non-segmental vitiligo often shows limited response to standard therapies. The IFN-&#x3b3;-JAK-STAT pathway plays a key role, and combining JAK inhibitors with NB-UVB may improve repigmentation. AIM: To evaluate the efficacy of JAK inhibitors (baricitinib or tofacitinib) plus NB-UVB versus NB-UVB without JAK inhibitors in adult NSV. METHODS: PubMed, Cochrane, and ClinicalTrials.gov were searched till August 2024 for randomized controlled trials. Four studies, comprising 217 adults (121 in the combination group and 96 in the control group), were analyzed using RevMan 5.4. Bias was assessed via Newcastle-Ottawa, Cochrane ROB-2, and ROBINS-I tools. RESULTS: Combination therapy significantly reduced total VASI compared to controls (MD = -4.96, 95% CI [-9.29, -0.63], p&#x2009;=&#x2009;0.02), with a greater effect on sensitivity analysis (MD = -6.84, p&#x2009;=&#x2009;0.0007). Significant reductions were seen in face/neck (MD = -0.17, p&#x2009;=&#x2009;0.002), trunk (MD = -3.62, p&#x2009;=&#x2009;0.0001); acral (MD = -0.85, p&#x2009;=&#x2009;0.0002) and extremity (MD = -4.61, p&#x2009;<&#x2009;0.00001) regions after sensitivity analysis. Patients were more likely to achieve &#x2265;50% (RR = 6.87, p&#x2009;<&#x2009;0.00001) and &#x2265;75% (RR = 15.13, p&#x2009;=&#x2009;0.006) repigmentation. CONCLUSIONS: JAK inhibitor plus NB-UVB markedly improves the repigmentation in adult NSV compared to NB-UVB alone.

Humans

Comparative Efficacy of Janus Kinase Inhibitors Indicated for Severe Alopecia Areata: A Bayesian Network Meta-Analysis and Matching-Adjusted Indirect Comparison.

Systemic Janus kinase inhibitors (JAKIs) have markedly advanced the therapeutic landscape for alopecia areata (AA). Although baricitinib and ritlecitinib are approved in the United States (US) and Europe, and deuruxolitinib in the US for severe AA, the lack of head-to-head randomized controlled trials (RCTs) limits evidence-based prescribing decisions. Moreover, prior meta-analyses excluded data on certain oral JAKIs or incorporated findings from agents and dosing regimens that were abandoned, investigational, clinically ineffective, or associated with unacceptable safety profiles. To compare the efficacy of oral JAKIs, limited to FDA, EMA, or MHRA approved drugs and doses-baricitinib (2 and 4&#x2009;mg QD), ritlecitinib (50&#x2009;mg QD), and deuruxolitinib (8&#x2009;mg BID)-for severe AA, using advanced indirect comparison methodologies. A systematic review was performed following PRISMA 2020 guidelines (CRD420251116775). Bayesian network meta-analysis (NMA) synthesized data from RCTs reporting Week 24 outcomes on Severity of Alopecia Tool (SALT) &#x2264;&#x2009;10 and SALT &#x2264;&#x2009;20 thresholds. Multilevel network meta-regression (ML-NMR) evaluated heterogeneity and adjusted for baseline imbalances. Additionally, unanchored matching-adjusted indirect comparisons (MAIC) were conducted using individual patient-level data from THRIVE trials. Surface under the cumulative ranking (SUCRA) values were calculated to rank treatments. Seven RCTs (n&#x2009;=&#x2009;4560 participants) were included. Deuruxolitinib 8&#x2009;mg significantly outperformed baricitinib 2 and 4&#x2009;mg on both SALT endpoints. Differences with ritlecitinib 50&#x2009;mg were directionally favorable for deuruxolitinib but not statistically significant in NMA and ML-NMR models. MAICs confirmed superior odds for deuruxolitinib versus baricitinib 2&#x2009;mg (OR&#x2009;=&#x2009;71.55) and ritlecitinib (OR&#x2009;=&#x2009;18.27) for SALT &#x2264;&#x2009;20. SUCRA rankings also consistently favored deuruxolitinib. Among approved oral JAKIs, deuruxolitinib 8&#x2009;mg shows the highest short-term efficacy for severe AA. These findings provide preliminary evidence to guide treatment decisions but should be interpreted as exploratory pending confirmation.

Humans

Ghrelin Receptor Deletion or Pharmacological Inhibition Improves Muscle Function in Aging Male Mice.

Sarcopenia is characterized by age-related declines in muscle strength and mass, along with impaired physical function. It remains an unmet medical need, and there are no pharmacological interventions approved for this indication. The activation of growth hormone secretagogue receptor (GHSR)-1a, also known as ghrelin receptor, stimulates food intake and has acute anabolic effects. However, its impact on aging muscles remains uncertain. We examined the effects of GHSR-1a deletion on sarcopenia measurements (muscle mass, strength, and endurance) by comparing young and aged male GHSR-1a knockout (KO) and wildtype (WT) mice (6-, 24-, and 28-month-old). Deletion of GHSR-1a improved muscle fatigue resistance, endurance, and muscle strength during aging without affecting muscle mass or longevity. Since muscle endurance is closely related to mitochondrial function, we examined mitochondrial biogenesis marker PGC-1&#x3b1; and mitophagy signaling via PINK1/p62 and found them improved in old mice with GHSR deletion. Proteomics analysis also revealed that mitochondrial components remain central for maintaining muscle mass and function. We further investigated the effects of pharmacological inhibition of GHSR-1a by its inverse agonist, PF-5190457, in male WT mice. PF-5190457 mimicked the effects of GHSR-1a deletion, including improved endurance and increased markers of mitochondrial biogenesis (PGC-1&#x3b1;) and different mitophagy markers (LC3II and Bnip3). PF-5190457 also reduced body weight and adiposity, which were not observed with GHSR-1a deletion. Overall, these findings suggest that GHSR-1a is a promising therapeutic target for age-related sarcopenia.

Receptors, Ghrelin

Impact of Albuminuria-Lowering Treatments on Cardiovascular Predictive Ceramides in Diabetes: Post Hoc Analysis of the ROTATE Trials.

AIM: Cardiovascular disease (CVD) is the leading cause of mortality in individuals with diabetes. Diabetic kidney disease, closely related to CVD risk, is prevalent in up to 40% of this population. Emerging evidence suggests ceramide lipids as accurate biomarkers for CVD. We assessed the effect of four albuminuria-lowering drugs on CVD-related ceramides in diabetes by post hoc analysis of the ROTATE trials. MATERIALS AND METHODS: Twenty six adults with type 1 (T1D) as well as 37 with type 2 diabetes (T2D) with a urine albumin-creatinine ratio (UACR) of 30-500&#x2009;mg/g participated in a 4-week 4-time randomized crossover study with periods of telmisartan, empagliflozin, linagliptin and baricitinib treatment, each separated by a 4-week washout period. Blood samples were collected at the beginning and end of each period and ceramide lipids (Cer16, Cer18, Cer20, Cer22, Cer24 and Cer24:1) were measured. The effect of each treatment was evaluated using linear mixed-effect models. RESULTS: At baseline, individuals with T2D had greater levels of Cer22 and Cer24 compared to the individuals with T1D. Among the treatments, linagliptin was the only drug that demonstrated a reduction of Cer22, Cer24 and Cer24:1 from baseline by 22.6% (95% CI: -33.58; -9.79, p&#x2009;=&#x2009;0.001), 25.7% (95% CI: -38.94; -9.69, p&#x2009;=&#x2009;0.003) and 19.6% (95% CI: -31.34; -5.95, p&#x2009;=&#x2009;0.007), respectively. No changes in the ceramides were observed for the other drugs. CONCLUSION: Our exploratory findings suggest that certain albuminuria-lowering drugs may affect ceramide levels as a secondary effect. However, further mechanistic investigations are needed.

Humans

A Randomized Phase II Study of Combination Atezolizumab and Varlilumab (CDX-1127) with or without Cobimetinib in Previously Treated Unresectable Biliary Tract Cancer.

PURPOSE: The addition of MEK inhibition (MEKi) to programmed cell death ligand 1 (PD-L1) blockade improves progression-free survival (PFS) in patients with advanced biliary tract cancer. Although MEK inhibitors may increase tumor cell immunogenicity, they can impair T-cell priming/effector function, limiting combination efficacy. We hypothesized that the addition of a CD27 agonist could restore T-cell function and enhance antitumor immunity in this combination. PATIENTS AND METHODS: We conducted a randomized, phase II trial evaluating atezolizumab (840 mg, intravenously, days 1 and 15) in combination with the CD27 costimulatory monoclonal antibody [CDX-1127/varlilumab (3 mg/kg, intravenously, days 1 and 15)], with/without the addition of an MEK inhibitor [cobimetinib (60 mg, orally, daily, days 1-21, off days 22-28)] in unresectable biliary tract cancer following at least one metastatic therapy. Overall response rate (ORR) and PFS were coprimary endpoints. Treatment-related changes in CD8+ tumor-infiltrating lymphocytes (TIL) were the primary correlative outcomes. RESULTS: The trial was closed early following interim preplanned ORR analysis. At closure, 57 patients had been enrolled [n = 29 in the cobimetinib + atezolizumab + varlilumab (CAV) arm; n = 28 in the atezolizumab + varlilumab (AV) arm]. A majority (67%) had intrahepatic cholangiocarcinoma, and 32% were immunotherapy experienced. Both regimens were well tolerated without new safety signals. Objective responses were rare [0% (CAV); 3.8% (AV)]. The median PFS (mPFS) was 2.40 (CAV) and 1.84 (AV) months [hazard ratio (HR), 0.67; 95% confidence interval (CI), 0.38-1.18]. Among immunotherapy-experienced patients, the mPFS was 3.62 (CAV) and 1.84 (AV) months (HR, 0.54; 95% CI, 0.18-1.62). Treatment with CAV increased intratumoral CD8+ T-cell density compared with treatment with AV. CONCLUSIONS: The combinations of atezolizumab and varlilumab with/without cobimetinib were safe, but neither meaningfully improved outcomes in biliary tract cancer treated in the later lines. Correlative tissue studies validated preclinical work that MEKi increases CD8+ TILs.

Humans