Arginine and tryptophan-rich dendritic antimicrobial peptides that disrupt membranes for bacterial infection in vivo

The potent antibacterial activity and low resistance of antimicrobial peptides (AMPs) render them potential candidates for treating multidrug-resistant bacterial infections. Herein, a minimalist design strategy was proposed employing the "golden partner" combination of arginine (R) and tryptophan (W), along with a dendritic structure to design AMPs. By extension, the α/ε-amino group and the carboxyl group of lysine (K) were utilized to link R and W, forming dendritic peptide templates αRn(εRn)KWm-NH2 and αWn(εWn)KRm-NH2, respectively. The corresponding linear peptide templates R2nKWm-NH2 and W2nKRm-NH2 were used as controls. Their physicochemical properties, activity, toxicity, and stability were compared. Among these new peptides, the dendritic peptide R2(R2)KW4 was screened as a prospective candidate owing to its preferable antibacterial properties, biocompatibility, and stability. Additionally, R2(R2)KW4 not only effectively restrained the progression of antibiotic resistance, but also demonstrated synergistic utility when combined with conventional antibiotics due to its unique membrane-disruptive mechanism. Furthermore, R2(R2)KW4 possessed low toxicity (LD50 = 109.31 mg/kg) in vivo, while efficiently clearing E. coli in pulmonary-infected mice. In conclusion, R2(R2)KW4 has the potential to become an antimicrobial regent or adjuvant, and the minimalist design strategy of dendritic peptides provides innovative and encouraging thoughts in designing AMPs.

Novel β-Hairpin Antimicrobial Peptide Containing the β-Turn Sequence of -NG- and the Tryptophan Zippers Facilitate Self-Assembly into Nanofibers, Exhibiting Excellent Antimicrobial Performance

Antimicrobial peptides (AMPs) have emerged as promising agents to combat the antibiotic resistance crisis due to their rapid bactericidal activity and low propensity for drug resistance. However, AMPs face challenges in terms of balancing enhanced antimicrobial efficacy with increased toxicity during modification processes. In this study, de novo d-type β-hairpin AMPs are designed. The conformational transformation of self-assembling peptide W-4 in the environment of the bacterial membrane and the erythrocyte membrane affected its antibacterial activity and hemolytic activity and finally showed a high antibacterial effect and low toxicity. Furthermore, W-4 displays remarkable stability, minimal occurrence of drug resistance, and synergistic effects when combined with antibiotics. The in vivo studies confirm its high safety and potent wound-healing properties at the sites infected by bacteria. This study substantiates that nanostructured AMPs possess enhanced biocompatibility. These advances reveal the superiority of self-assembled AMPs and contribute to the development of nanoantibacterial materials.

A novel antimicrobial peptide with broad-spectrum and exceptional stability derived from the natural peptide Brevicidine

The global issue of antibiotic resistance is increasingly severe, highlighting the urgent necessity for the development of new antibiotics. Brevicidine, a natural cyclic lipopeptide, exhibits remarkable antimicrobial activity against Gram-negative bacteria. In this study, a comprehensive structure-activity relationship of Brevicidine was investigated through 20 newly synthesized cyclic lipopeptide analogs, resulting in the identification of an optimal linear analog 22. The sequence of analog 22 consisted of five d-amino acids and four non-natural amino acid 2,5-diaminovaleric acid (Orn) and conjugated with decanoic acid at N-terminal. Compared to Brevicidine, analog 22 was easier to synthesize, and exerted broad spectrum antimicrobial activity and excellent stability (t1/2 = 40.98 h). Additionally, analog 22 demonstrated a rapid bactericidal effect by permeating non-specifically through the bacterial membranes, thereby minimizing the likelihood of inducing resistance. Moreover, it exhibited remarkable efficacy in combating bacterial biofilms and reversing bacterial resistance to conventional antibiotics. Furthermore, it effectively suppressed the growth of bacteria in vital organs of mice infected with S. aureus ATCC 25923. In conclusion, analog 22 may represent a potential antimicrobial peptide for further optimization.

Dexamethasone relieves the inflammatory response caused by inguinal hernia meshes through miR-155

BACKGROUND

Inguinal hernia is a relatively common condition. Most patients with inguinal hernia require surgery. At present, mesh repair is one of the most effective methods to treat inguinal hernia, but insertion of the mesh can cause inflammation. Dexamethasone (DEX) can treat inflammation, but the mechanism by which DEX alleviates inflammation caused by inguinal hernia mesh placement remains unclear.

METHOD

We randomly divided rats into groups: negative control (NC), inguinal hernia (IH), polypropylene mesh (PM), DEX treatment, and miR-155 treatment groups. RT-qPCR was performed to determine the expression of miR-155. ELISA was implemented to determine the secretion of IL-1β, IL-6, and IL-18. Western blotting was used to detect caspase-1, JAK1, p-JAK1, STAT3, and p-STAT3 expression. A dual-luciferase reporter gene array identified a connection between miR-155 and JAK1.

RESULTS

The results revealed that the expression of miR-155, IL-1β, IL-6, and IL-18 was upregulated in the PM group. After DEX treatment, the secretion of miR-155, caspase-1, IL-1β, IL-6, and IL-18 decreased. Dual luciferase results confirmed that miR-155 induced the targeted downregulation of JAK1, while a miR-155 mimic reversed the therapeutic effect of DEX, and the expression levels of p-JAK1 and p-STAT3 increased.

CONCLUSION

DEX regulates the JAK1/STAT3 signaling pathway through miR-155 to relieve inflammation caused by inguinal hernia meshes.

Structure modification of anoplin for fighting resistant bacteria

The emergence of bacterial resistance has posed a significant challenge to clinical antimicrobial treatment, rendering commonly used antibiotics ineffective. The development of novel antimicrobial agents and strategies is imperative for the treatment of resistant bacterial infections. Antimicrobial peptides (AMPs) are considered a promising class of antimicrobial agents due to their low propensity for resistance and broad-spectrum activity. Anoplin is a small linear α-helical natural antimicrobial peptide that was isolated from the venom of the solitary wasp Anplius samariensis. It exhibits rich biological activity, particularly broad-spectrum antimicrobial activity and low hemolytic activity. Over the past three decades, more than 40 research publications on anoplin have been made available online. This review focuses on the advancements of anoplin in antimicrobial research, encompassing its sources, characterization, antimicrobial activity, influencing factors and structural modifications. The aim is to provide assistances for the development of new antimicrobial agents that can combat bacterial resistance.

[Timing and surgery option of keratinized mucosa augmentation around implant site]

In recent years, clinicians have paid more attention to the biological and esthetic effects of the 2 mm keratinized mucosa width (KMW) around dental implant. How to increase the keratinized mucosa is the focus of clinicians. While the free gingival graft (FGG) is still the gold standard of keratinized mucosa augmentation, alveolar ridge preservation (ARP), connective tissue graft (CTG) and apically positioned flap (APF) can also be used to obtain more than 2 mm keratinized mucosa width when they are used before implantation, with implantation, within the implant-healing phase, with second stage of implantation or after rehabilitation according to different indications. This article comprehensively summarizes the influencing factors of timing and surgical procedures for keratinized mucosa augmentation, providing guidance for clinicians to treat peri-implant keratinized mucosa deficiencies.

Sintilimab, SBRT and GM-CSF for Metastatic NSCLC: A Prospective, Multicenter, Phase II Trial

PURPOSE/OBJECTIVE(S)

PD-1/PD-L1 inhibitors have transformed the therapeutic landscape in metastatic non-small cell lung cancer (NSCLC). However, the objective response rate (ORR) remains limited in unselected population. Incorporating SBRT to PD-1/PD-L1 inhibitors may improve treatment efficacy and the anti-tumor immunity induced by SBRT may be enhanced by GM-CSF, which plays a pivotal role in dendritic cell differentiation and maturation. The current trial (NCT04106180) is the first prospective, multicenter, phase II study assessing the safety and efficacy of a PD-1 inhibitor (Sintilimab), SBRT and GM-CSF in metastatic NSCLC patients without sensitizing driver mutations.

MATERIALS/METHODS

Metastatic EGFR/ALK negative NSCLC pts who had failed first-line standard chemotherapy were eligible. Pts received SBRT (8 Gy*3) to one lesion, followed by Sintilimab (200 mg d1, every 3 weeks) and GM-CSF (125 μg/m2 d1-d14, cycle 1) within 3 weeks after SBRT. Sintilimab would be given continuously until disease progression, unacceptable toxicity, or up to 35 cycles. Primary end point is ORR. Secondary end points are safety, out-of-field response rate, overall survival (OS), progression free survival (PFS). The trial was designed to enroll 56 patients and if ≥17 pts evaluated had an objective response, it was regarded as positive.

RESULTS

By the time of 2022/10/30, the trial was early closed after 18 of the 51pts enrolled from 6 academic centers documented PR. The majority of pts were male, ECOG 1 and non-squamous NSCLC, having more than 5 lesions at baseline, with a median age of 62 (range, 32-74). The sites of SBRT included lung (n = 20), regional lymph node (n = 16), pleural nodule (n = 5), vertebra (n = 3), distant lymph node (n = 3), liver (n = 2) and others (n = 2). Treatment-related adverse event (TRAE) occurred in most pts and grade 3 TRAE occurred in 6 (11.8%) pts. No grade 4-5 TRAE occurred and the most common grade 3 TRAEs were ALT/AST elevation (n = 2), transient acute heart failure (recovered within 7 days) (n = 1), leucopenia/neutropenia (n = 2), pneumonitis (n = 1) and creatinine elevation (n = 1). With a median follow-up of 19.2 (range, 4.6-35.4) months, 49 pts had evaluable efficacy, with 18 PR, 15 SD and 16 PD. Median PFS and OS were 5.9 (95% CI, 3.9-9.2) and 16.2 (95% CI, 12.6-34.1) months, respectively. The results of biomarker testing will also be presented.

CONCLUSION

Triple combination of Sintilimab, SBRT and GM-CSF is safe and shows promising efficacy in metastatic EGFR/ALK negative NSCLC.

Efficacy and safety of methylene blue injection for intractable idiopathic pruritus ani: a single-arm metaanalysis and systematic review

PURPOSE

To evaluate how effective methylene blue injection was at treating intractable idiopathic pruritus ani.

METHODS

A comprehensive literature search of the PubMed, Embase, Cochrane library, and Web of Science databases was conducted. All clinical studies (prospective and retrospective) that evaluated the efficacy of methylene blue in treating intractable idiopathic pruritus ani were included. Studies that reported the resolution rate, after a single injection and after a second injection, the recurrence rate, symptom scores, and transient complications of methylene blue injections in treating intractable idiopathic pruritus ani were included.

RESULTS

The seven selected studies included 225 patients with idiopathic pruritus ani. The resolution rates after a single injection and after a second injection was 0.761 (0.649-0.873, P < 0.01, I2 = 69.06%) and 0.854 (0.752-0.955, P < 0.01, I2 = 77.391%), respectively, the remission rates at 1, 3, and 5 years were 0.753 (0.612-0.893, P < 0.001), 0.773 (0.675-0.871, P < 0.001) and 0.240 (0.033-0.447, P < 0.001), respectively, the effect value of the merger was 0.569 (0.367-0.772, P < 0.001, I2 = 79.199%), and the recurrence rates at 1, 2, 3, and < 1 year were 0.202 (0.083-0.322, P < 0.001), 0.533 (0.285-0.781, P < 0.001), 0.437 (-0.044, 0.917, P < 0.001) and 0.067 (0.023-0.111, P < 0.001), respectively. The effect value of the merger was 0.223 (0.126-0.319, P < 0.001, I2 = 75.840).

CONCLUSION

Using methylene blue injections to treat intractable idiopathic pruritus ani is relatively efficacious, resulting in a relatively low recurrence rate and no severe complications. However, the available literature was of poor quality. Therefore, higher quality studies are necessary to confirm that methylene blue injection is efficacious for pruritus ani, such as a randomized prospective multicenter studies.

Pattern of Failure and Re-Irradiation for Stereotactic Radiotherapy Treated Brain Metastases from Non-Small Cell Lung Cancer (NSCLC)

PURPOSE/OBJECTIVE(S)

Hypofractionated stereotactic radiotherapy (SRT) has been increasingly used for brain metastases (BMs) from non-small cell lung cancer (NSCLC). However, the prognostic factors, pattern of failure and clinical utility of re-irradiation for these patients remain have not been fully understood.

MATERIALS/METHODS

Metastatic NSCLC patients receiving SRT that covering all of the intracranial tumor lesions and without prior whole brain radiotherapy (WBRT) were retrospectively enrolled. Local recurrence free survival (LRFS), intracranial progression free survival (iPFS) and overall survival (OS) were calculated from the initiation of SRT. Post intracranial progression survival (OS2) was measured from the initial intracranial disease progression.

RESULTS

From 2018/05 to 2022/05, 218 patients were identified, with 142 (65.1%) having only one BM and 76 (34.9%) harboring 2-5 BMs. With a median follow-up of 31.1 (range, 1.0-44.6) months, median LRFS, iPFS and OS was 39.1, 26.6 and 31.1 months, respectively. No statistical difference of LRFS, iPFS and OS were found between patients with different numbers of BM. Nevertheless, patients receiving concurrent systemic therapy had significantly longer LRFS (HR = 0.35, p = 0.002), iPFS (HR = 0.57, p = 0.044) and OS (HR = 0.37, p = 0.001), when compared with those receiving SRT alone. By now, intracranial disease progression (iPD) was documented in 59 patients, with original site PD (OPD), new site PD (NPD) and both sites PD (BPD) occurring in 20 (33.9%), 17 (28.8%) and 22 (37.3%), respectively. Among the 59 patients, 19 (32.2%) received second-course SRT (re-SRT) targeting the intracranial progressive tumor lesions and re-SRT led to improved OS2 (22.7 vs 12.1 months, HR = 0.29, 95% CI 0.08-0.97, p = 0.045), which remained as an independent prognostic factor after multiple-variate Cox analyses.

CONCLUSION

The status of systemic therapy, but not the number of BMs, may impact the survival outcomes of SRT-treated BMs from NSCLC. Some patients may benefit from re-SRT, which warranted future validation.

Oligo-Residual Disease in PD-1/PD-L1 Inhibitors Treated Metastatic Non-Small Cell Lung Cancer: Incidence, Pattern of Failure and Clinical Value of Local Consolidative Therapy

PURPOSE/OBJECTIVE(S)

Growing numbers of clinical trials are testing the efficacy of incorporating local therapy into programmed death receptor (ligand) 1 (PD-1/PD-L1) inhibitors in metastatic non-small cell lung cancer (NSCLC), but the optimal timing and patient selection are still controversial. We aimed to examine the patterns of maximum tumor response and treatment failure in PD-1/PD-L1 inhibitor-treated NSCLC, and explore the potential clinical value of local consolidative therapy (LCT) in those with oligo-residual disease (ORD).

MATERIALS/METHODS

Metastatic NSCLC treated with PD-1/PD-L1 inhibitors in three academic centers from May 2018 to December 2021 were retrospectively reviewed and those derived clinical benefit, defined as having objective response or durable stable disease lasting≥6months, were finally enrolled. Patterns of tumor response and treatment failure were extensively analyzed. ORD was defined as residual tumor distribution limited to 3 organs and 5 lesions, otherwise was defined as multiple residual disease (MRD). Local therapies targeting the residual tumor lesions performed after PD-1/PD-L1 inhibitors initiation and before initial disease progression, were considered as LCT. The primary endpoints were the overall survival (OS) and progression-free survival (PFS).

RESULTS

Of the 318 patients enrolled, ORD and MRD were documented in 122 (38.4%) and 196 (61.6%) patients, respectively. Those who developed ORD had a significantly longer OS than those with MRD (p = 0.006). The median time to best response was 4 months and more than 50% of the initial disease progression developed only from the residual tumor lesions, providing the preliminary rationale of LCT. Among the 122 patients with ORD, those receiving LCT (n = 39) had significantly longer PFS (p = 0.04) and OS (p<0.001) than those without LCT. Moreover, LCT remained one of the independent predictors of improved PFS and OS after Cox analyses.

CONCLUSION

Local consolidative therapy seems to be feasible and may provide extra survival benefit for metastatic NSCLC patients with oligo-residual disease after PD-1/PD-L1 inhibitor treatment.

Structure-Activity Relationship Study of Antimicrobial Peptide PE2 Delivered Novel Linear Derivatives with Potential of Eradicating Biofilms and Low Incidence of Drug Resistance

The ongoing emergence of antibiotic-resistant pathogens had been dramatically stimulating and accelerating the need for new drugs. PE2 is a kind of cyclic lipopeptide with broad-spectrum antimicrobial activity. Herein, its structure-activity relationship was systematically investigated by employing 4 cyclic analogues and 23 linear analogues for the first time. The screened linear analogues 26 and 27 bearing different fatty acyls at N-termini and a Tyr residue at the 9th position had superior potency compared to the cyclic analogues and showed equivalent antimicrobial activity compared with PE2. Notably, 26 and 27 exhibited significant ability against multidrug-resistant bacteria, favorable resistance to protease, excellent performance against biofilm, low drug resistance, and high effectiveness against the mice pneumonia model. The antibacterial mechanisms of PE2 and linear derivatives 26 and 27 were also preliminarily explored in this study. As described above, 26 and 27 are promising antimicrobial candidates for the treatment of infections associated with drug-resistant bacteria.

[Treatment and prognosis analysis of 488 patients with FIGO 2018 stage Ⅲc squamous cervical cancer]

Objective: To analyze the treatment and prognosis of patients with International Federation of Gynecology and Obstetrics (FIGO) 2018 stage Ⅲc cervical squamous cell carcinoma. Methods: A total of 488 patients at Zhejiang Cancer Hospital between May, 2013 to May, 2015 were enrolled. The clinical characteristics and prognosis were compared according to the treatment mode (surgery combined with postoperative chemoradiotherapy vs radical concurrent chemoradiotherapy). The median follow-up time was (96±12) months ( range time from 84 to 108 months). Results: (1) The data were divided into surgery combined with chemoradiotherapy group (surgery group) and concurrent chemoradiotherapy group (radiotherapy group), including 324 cases in the surgery group and 164 cases in the radiotherapy group. There were significant differences in Eastern Cooperation Oncology Group (ECOG) score, FIGO 2018 stage, large tumors (≥4 cm), total treatment time and total treatment cost between the two groups (all P<0.01). (2) Prognosis: ① for stage Ⅲc1 patients, there were 299 patients in the surgery group with 250 patients survived (83.6%). In the radiotherapy group, 74 patients survived (52.9%). The difference of survival rates between the two groups was statistically significant (P<0.001). For stage Ⅲc2 patients, there were 25 patients in surgery group with 12 patients survived (48.0%). In the radiotherapy group, there were 24 cases, 8 cases survived, the survival rate was 33.3%. There was no significant difference between the two groups (P=0.296). ② For patients with large tumors (≥4 cm) in the surgery group, there were 138 patients in the Ⅲc1 group with 112 patients survived (81.2%); in the radiotherapy group, there were 108 cases with 56 cases survived (51.9%). The difference between the two groups was statistically significant (P<0.001). Large tumors accounted for 46.2% (138/299) vs 77.1% (108/140) in the surgery group and radiotherapy group. The difference between the two groups was statistically significant (P<0.001). Further stratified analysis, a total of 46 patients with large tumors of FIGO 2009 stage Ⅱb in the radiotherapy group were extracted, and the survival rate was 67.4%, there was no significant difference compared with the surgery group (81.2%; P=0.052). ③ Of 126 patients with common iliac lymph node, 83 patients survived, with a survival rate of 65.9% (83/126). In the surgery group, 48 patients survived and 17 died, with a survival rate of 73.8%. In the radiotherapy group, 35 patients survived and 26 died, with a survival rate of 57.4%. There were no significant difference between the two groups (P=0.051). (3) Side effects: the incidence of lymphocysts and intestinal obstruction in the surgery group were higher than those in the radiotherapy group, and the incidence of ureteral obstruction and acute and chronic radiation enteritis were lower than those in the radiotherapy group, and there were statistically significant differences (all P<0.01). Conclusions: For stage Ⅲc1 patients who meet the conditions for surgery, surgery combined with postoperative adjuvant chemoradiotherapy and radical chemoradiotherapy are acceptable treatment methods regardless of pelvic lymph node metastasis (excluding common iliac lymph node metastasis), even if the maximum diameter of the tumor is ≥4 cm. For patients with common iliac lymph node metastasis and stage Ⅲc2, there is no significant difference in the survival rate between the two treatment methods. Based on the duration of treatment and economic considerations, concurrent chemoradiotherapy is recommended for the patients.

Shared genetic architecture between type 2 diabetes and COVID-19 severity

PURPOSE

Patients with type 2 diabetes (T2D) have demonstrated a higher risk for developing more severe cases of COVID-19, but the complex genetic mechanism between them is still unknown. The aim of the present study was to untangle this relationship using genetically based approaches.

METHODS

By leveraging large-scale genome-wide association study (GWAS) summary statistics of T2D and COVID-19 severity, linkage disequilibrium score regression and Mendelian randomization (MR) analyses were utilized to quantify the genetic correlations and causal relationships between the two traits. Gene-based association and enrichment analysis were further applied to identify putative functional pathways shared between T2D and COVID-19 severity.

RESULTS

Significant, moderate genetic correlations were detected between T2D and COVID-19 hospitalization (r_g = 0.156, SE = 0.057, p = 0.005) or severe disease (r_g = 0.155, SE = 0.057, p = 0.006). MR analysis did not support evidence for a causal effect of T2D on COVID-19 hospitalization (OR 1.030, 95% CI 0.979, 1.084, p = 0.259) or severe disease (OR 0.999, 95% CI 0.934, 1.069, p = 0.982). Genes having p_gene < 0.05 for both T2D and COVID-19 severe were significantly enriched for biological pathways, such as response to type I interferon, glutathione derivative metabolic process and glutathione derivative biosynthetic process.

CONCLUSIONS

Our findings further confirm the comorbidity of T2D and COVID-19 severity, but a non-causal impact of T2D on severe COVID-19. Shared genetically modulated molecular mechanisms underlying the co-occurrence of the two disorders are crucial for identifying therapeutic targets.

One New Acid-Activated Hybrid Anticancer Peptide by Coupling with a Desirable pH-Sensitive Anionic Partner Peptide

Anticancer peptides (ACPs) are promising antitumor resources, and developing acid-activated ACPs as more effective and selective antitumor drugs would represent new progress in cancer therapy. In this study, we designed a new class of acid-activated hybrid peptides LK-LE by altering the charge shielding position of the anionic binding partner LE based on the cationic ACP LK and investigated their pH response, cytotoxic activity, and serum stability, in hoping to achieve a desirable acid-activatable ACP. As expected, the obtained hybrid peptides could be activated and exhibit a remarkable antitumor activity by rapid membrane disruption at acidic pH, whereas its killing activity could be alleviated at normal pH, showing a significant pH response compared with LK. Importantly, this study found that the peptide LK-LE3 with the charge shielding in the N-terminal of LK displayed notably low cytotoxicity and more stability, demonstrating that the position of charge masking is extremely important for the improvement of peptide toxicity and stability. In short, our work opens a new avenue to design promising acid-activated ACPs as potential targeting agents for cancer treatment.

The Role of Sarcopenia in Overactive Bladder in Adults in the United States: Retrospective Analysis of NHANES 2011-2018

PURPOSE

To investigate the association between sarcopenia and overactive bladder (OAB) in a United States adult population from 2011 to 2018, and whether sarcopenia can predict the risk of OAB.

MATERIALS AND METHODS

We analyzed data from the 2011-2018 National Health and Nutrition Examination Survey in a cross-sectional study(NHANES) of 8746 participants, of whom 1213 were diagnosed with OAB, we analyzed correlations by sex, age, race, education level, marital status, household income-to-poverty ratio, hypertension, diabetes, strenuous work activity, moderate work activity, strenuous recreational activity, moderate recreational activity, blood urea nitrogen, creatinine, and uric acid levels using restricted cubic spline plots of dose-response curves, univariate and multivariate Logistic regression. Models based on sex, age, education, household income to poverty ratio, hypertension, diabetes, sarcopenia index, and cotinine were developed and evaluated using Nomogram, calibration curves, receiver operating characteristic curves, and clinical decision curves.

RESULTS

Of the 1213 OAB patients, 388 (32.0%) were male and 825 (68.0%) were female. Univariate and multivariate Logistic regression analysis showed that sarcopenia index was negatively correlated with the prevalence of OAB (OR=0.084, 95% CI, 0.056 - 0.130, P <0.001;OR=0.456, 95%CI, 0.215-0.968, P= 0.0041). Dose curve analysis of the sarcopenia index and prevalence of OAB showed that the prevalence of OAB decreased significantly with increasing sarcopenia index. Sarcopenia was positively correlated with OAB (OR=2.400, 95%CI, 2.000 - 2.800, P <0.001;OR=1.46, 95%CI, 1.096 -1.953, P = 0.010). In addition, our model shows that sarcopenia can predict the prevalence of OAB (AUC = 0.750) and has some clinical decision-making implications.

CONCLUSION

Sarcopenia is positively associated with the risk of OAB in United States adults and can be used as a predictor of OAB prevalence.

Short, mirror-symmetric antimicrobial peptides centered on "RRR" have broad-spectrum antibacterial activity with low drug resistance and toxicity

The increasingly severe bacterial resistance worldwide pushes people to discover and design potential antibacterial drugs unavoidably. In this work, a series of short, mirror-symmetric peptides were designed and successfully synthesized, centered on "RRR" and labeled with hydrophobic amino acids at both ends. Based on the structure-activity relationship analysis, LWWR (LWWRRRWWL-NH₂) was screened as a desirable mirror-symmetric peptide for further study. As expected, LWWR displayed broad-spectrum antibacterial activity against the standard bacteria and antibiotic-resistant strains. Undoubtedly, the high stability of LWWR in a complex physiological environment was an essential guarantee to maximizing its antibacterial activity. Indeed, LWWR also exhibited a rapid bactericidal speed and a low tendency to develop bacterial resistance, based on the multiple actions of non-receptor-mediated membrane actions and intra-cellular mechanisms. Surprisingly, although LWWR showed similar in vivo antibacterial activity compared with Polymyxin B and Melittin, the in vivo safety of LWWR was far higher than that of them, so LWWR had better therapeutic potential. In summary, the desirable mirror-symmetric peptide LWWR was promised as a potential antibacterial agent to confront the antibiotics resistance crisis. STATEMENT OF SIGNIFICANCE: Witnessing the growing problem of antibiotic resistance, a series of short, mirror-symmetric peptides based on the symmetric center "RRR" and hydrophobic terminals were designed and synthesized in this study. Among, LWWR (LWWRRRWWL-NH₂) presented broad-spectrum antibacterial activity both in vitro and in vivo due to its multiple mechanisms and good stability. Meanwhile, the low drug resistance and toxicity of LWWR also suggested its potential for clinical application. The findings of this study will provide some inspiration for the design and development of potential antibacterial agents, and contribute to the elimination of bacterial infections worldwide as soon as possible.

Improving the Antimicrobial Performance of Amphiphilic Cationic Antimicrobial Peptides Using Glutamic Acid Full-Scan and Positive Charge Compensation Strategies

Nonselective toxicity of antimicrobial peptides (AMPs) needs to be solved urgently for their application. Temporin-PE (T-PE, FLPIVAKLLSGLL-NH₂), an AMP extracted from skin secretions of frogs, has high toxicity and specific antimicrobial activity against Gram-positive bacteria. To improve the antimicrobial performance of T-PE, a series of T-PE analogues were designed and synthesized by glutamic acid full-scan, and then their key positions were replaced with lysine. Finally, E₁₁K₄K₁₀, the highest therapeutic indicial AMP, was screened out. E₁₁K₄K₁₀ was not easy to induce and produce drug-resistant bacteria when used alone, as well as it could also inhibit the development of the drug resistance of traditional antibiotics when it was used in combination with the traditional antibiotics. In addition, E₁₁K₄K₁₀ had an excellent therapeutic effect on a mouse model of pulmonary bacterial infection. Taken together, this study provides a new approach for the further improvement of new antimicrobial peptides against the antimicrobial-resistance crisis.

Pregnancy of cryopreserved ovine embryos at different developmental stages

BACKGROUND

Developmental stage and cryopreservation method have significant impact on the pregnancy rate after transfer of embryos produced in vivo.

OBJECTIVE

To determine the pregnancy outcomes from ovine embryos cryopreserved at different developmental stages.

MATERIALS AND METHODS

Embryos at different developmental stages were obtained from donor ewes through simultaneous estrus treatment and laparoscopic artificial insemination. Embryos, either cryopreserved via vitrification or slow freezing method, were implanted into recipient ewes. The pregnancy rate was determined 35 days after transfer.

RESULTS

The pregnancy rate of developing embryos increases after transfer from the morula stage, early blastocyst to expanded blastocyst stages (64.9%, 73.9% and 81.3%, respectively). However, cryopreservation significantly decreases the pregnancy rate of embryos at all three developmental stages, and there is no significant difference among developmental stages (43.9%, 43.7%, 52.9%, respectively). There is also no significant difference in the pregnancy rate between slowly-frozen embryos and vitrified embryos.

CONCLUSION

The pregnancy outcomes of embryo transfer is better at the expanded blastocyst stage than at earlier stages. However, no difference is observed in the pregnancy rate of embryos at different developmental stage after cryopreservation, either by slow freezing and vitrification. Cryopreservation methods for ovine embryos, both slow freezing and vitrification, need further improvement. doi.org/10.54680/fr22510110512.

[Effects of cinepazide maleate injection on blood pressure in patients with acute ischemic stroke and hypertension]

Objective: To investigate the blood pressure change in patients with acute ischemic stroke (AIS) and hypertension treated with cinepazide maleate injection. Methods: This was a subgroup analysis of post-marketing clinical confirmation study of cinepazide maleate injection for acute ischemic stroke: a randomized, double-blinded, multicenter, placebo-parallel controlled trial, which conducted in China from August 2016 to February 2019. Eligible patients fulfilled the inclusive criteria of acute anterior circulation ischemic stroke with National Institutes of Health Stroke Scale (NIHSS) scores of 7-25. The primary endpoints were mean blood pressure of AIS patients treated with cinepazide maleate or control, which were assessed during the treatment period (14 days), and the proportion of the patients with normal blood pressure was analyzed after the treatment period. Furthermore, a subgroup analysis was performed to investigate a possible effect of the history of hypertension on outcomes. Results: This analysis included 809 patients with hypertension. There was no significant difference in patients blood pressure and the proportion of patients with normal blood pressure (60.5% vs. 59.0%,P>0.05) between cinepazide maleate group and control group. Conclusion: Administration of cinepazide maleate injection does not affect the management of clinical blood pressure in patients with AIS.

Constructing New Acid-Activated Anticancer Peptide by Attaching a Desirable Anionic Binding Partner Peptide

Improving the cell selectivity of anticancer peptides (ACPs) is a major hurdle in their clinical utilization. In this study, a new acid-activated ACP was designed by conjugating a cationic ACP LK to its anionic binding partner peptide (LEH) via a disulfide linker to trigger antitumor activity at acidic pH while masking its killing activity at normal pH. Three anionic binding peptides containing different numbers of glutamic acid (Glu) and histidine were engineered to obtain an efficient acid-activated ACP. The conjugates LK-LEH2 and LK-LEH3 exhibited 6.1 and 8.0-fold higher killing activity at pH 6.0 relative to at pH 7.4, respectively, suggesting their excellent pH-dependent antitumor activity; and their cytotoxicity was 10-fold lower than that of LK. However, LK-LEH4 had no pH-responsive killing effect. Interestingly, increasing the number of Glu from 2 to 4 increased the pH-response of the physical mixture of LK and LEH; conversely, they weakly decreased the cytotoxicity of LK, suggesting that the conjugate connection was required to achieve excellent pH dependence while maintaining minimum toxicity. LK-LEH2 and LK-LEH3 were more enzymatically stable than LK, indicating their potential for in vivo application. Our work provided a basis for designing promising ACPs with good selectivity and low toxicity.

Novel Synovial Targeting Peptide-Sinomenine Conjugates as a Potential Strategy for the Treatment of Rheumatoid Arthritis

Sinomenine (SIN) is an effective anti-inflammatory agent, but its therapeutic efficacy is limited by its short half-life and the high dosage required. Tissue-specific strategies have the potential to overcome these limitations. The synovial homing peptide (CKSTHDRLC) was identified to have high synovial endothelium targeting affinity. In this work, two peptide-drug conjugates (PDCs), conjugate (L) and conjugate (C), were synthesized, in which SIN was covalently connected to the linear and cyclic synovial homing peptide, respectively, via a 6-aminocaproic acid linker. An evaluation of biostability showed that conjugate (C) was more stable in mouse serum and inflammatory joint homogenate than conjugate (L). The two conjugates gradually released free SIN. Interestingly, conjugate (L) self-cyclized via a disulfide bridge in a biological environment, which significantly impacted its biostability. It had an almost equipotent half-life in serum but faster degradation in the inflammatory joint than conjugate (C). Therefore, conjugate (C) exhibited better therapeutic efficacy and tissue targeting. All the results indicated that PDCs particularly in its cyclic form might be more efficient for targeted deliver and represent a potential strategy for the treatment of rheumatoid arthritis.

Racial/ethnic differences in cardiovascular outcomes in a universal healthcare system: insights from the CARTaGENE cohort

Background

While prior studies have shown racial/ethnic differences in cardiovascular (CV) outcomes within private or mixed health care systems, it remains uncertain whether inequalities in cardiovascular outcomes exist between different races and ethnicities in universal health care contexts. We aimed to determine whether there are racial/ethnicity disparities in long-term CV outcomes within a single-payer universal health care system.

Methods

The CARTaGENE study is a population-based prospective cohort study with enrollment of 19,996 individuals between 40–69 years in 2009, in the province of Quebec, Canada. Participants residing in four large metropolitan areas were randomly chosen from the provincial health insurance registry by strata of age, sex, and postal codes. Follow-up was available up to 2016. For this analysis, we retained only participants without prior known CV disease. The primary composite endpoint was time to the first CV event or intervention (CV death, acute coronary syndrome, heart failure, coronary revascularization, ischemic stroke, or peripheral vascular event or revascularization). We used unadjusted and adjusted Cox proportional hazard models to evaluate the association of self-defined race/ethnicity with the primary endpoint.

Results

There were 17,802 eligible participants with a mean age of 51 years (52.5% females) with 111,312 person-years of follow-up (median follow-up of 6.6 years). South Asian (SA) participants had the highest prevalence of diabetes mellitus (29%) and hypertension (32%). After adjustment for age and sex, SA ethnicity was associated with a 95% relative increase in risk for CV events, while East/Southeast Asian (ESA) ethnicity was associated with a 42% relative decrease in risk for CV events compared to White participants. After further adjustment for socioeconomic status and CV risk factors, ESA ethnicity remained associated with a similar decreased CV risk. In contrast, the association of SA ethnicity with increased CV risk was attenuated after full adjustment for baseline characteristics (Table 1).

Conclusions

Racial/ethnic disparities in long-term CV outcomes are present in a single-payer universal healthcare setting. ESA ethnicity was associated with a lower risk of long-term CV outcomes. Future studies are needed to corroborate the reduced risk of long-term major CV events associated with ESA ethnicity. Understanding the reasons related to potential CV protection with ESA ethnicity could facilitate endeavors to reduce long-term CV outcomes in other races/ethnicities.

Funding Acknowledgement

Type of funding sources: Public hospital(s). Main funding source(s): McGill Health University Center

Tuning the Activity of Anoplin by Dendrimerization of Lysine and Lipidation of the N-Terminal

Dendrimeric antimicrobial peptides or lipopeptides have strong transmembrane ability and antibacterial activity. To obtain some ideal antimicrobial peptides, anoplin, a natural antimicrobial peptide with weak antimicrobial activity, was modified by C-terminal dendrimerization using lysine and N-terminal lipidation using fatty acids. 2K-3A-C4, a trimer of anoplin, was dendrimerized by two lysines at the C-terminal and was lipidated by n-butyric acid at the N-terminal, and thus exhibited the best antibacterial activity. However, the trimer had high hemolytic activity. Finally, A-C8, a simple structural lipopeptide, which is not a dendrimer, was obtained following the lipidation of anoplin using octanoic acid; it exhibited the highest therapeutic index, which makes it a probable antibiotic and thus was screened out.

Novel Broad-Spectrum Antimicrobial Peptide Derived from Anoplin and Its Activity on Bacterial Pneumonia in Mice

The emergence of multidrug-resistant bacteria has major issues for treating bacterial pneumonia. Currently, anoplin (GLLKRIKTLL-NH₂) is a natural antimicrobial candidate derived from wasp venom. In this study, a series of new antimicrobial peptide (AMP) anoplin analogues were designed and synthesized. The relationship between their biological activities and their positive charge, hydrophobicity, amphipathicity, and secondary structure are described. The characteristic shared by these peptides is that positively charged amino acids and hydrophobic amino acids are severally arranged on the hydrophilic and hydrophobic surface of the α-helix to form a completely amphiphilic structure. To achieve ideal AMPs, below the range of the threshold of the cytotoxicity and hemolytic activity, their charges and hydrophobicity were increased as much. Among the new analogues, A-21 (KWWKKWKKWW-NH₂) exhibited the greatest antimicrobial activity (geometric mean of minimum inhibitory concentrations = 4.76 μM) against all the tested bacterial strains, high bacterial cell selectivity in vitro, high effectiveness against bacterial pneumonia in mice infected with Klebsiella pneumoniae, and low toxicity in mice (LD₅₀ = 82.01 mg/kg). A-21 exhibited a potent bacterial membrane-damaging mechanism and lipopolysaccharide-binding ability. These data provide evidence that A-21 is a promising antimicrobial candidate for the treatment of bacterial pneumonia.

New Antimicrobial Peptides with Repeating Unit against Multidrug-Resistant Bacteria

With the aim of tackling the increasingly serious antimicrobial resistance and improving the clinical potential of AMPs, a facile de novo strategy was adopted in this study, and a series of new peptides comprising repeating unit (WRX)_n (X represents I, L, F, W, and K; n = 2, 3, 4, or 5) and amidation at C-terminus were designed. Most of the newly designed peptides exhibited a broad range of excellent antimicrobial activities against various bacteria, especially difficult-to-kill multidrug-resistant bacteria clinical isolates. Among (WRK)₄ and (WRK)₅, with n = 4 and n = 5 of repeating unit WRK, the highest selectivity for anionic bacterial membranes over a zwitterionic mammalian cell membrane is presented with strong antimicrobial potential and low toxicity. Additionally, both (WRK)₄ and (WRK)₅ emerged with fast killing speed and low tendency of resistance in sharp contrast to the conventional antibiotics ciprofloxacin, gentamicin, and imipenem, as well as having antimicrobial activity through multiple mechanisms including a membrane-disruptive mechanism and an intramolecular mechanism (nucleic acid leakage, DNA binding and ROS generation) characterized by a series of assays. Furthermore, (WRK)₄ exerted impressive therapeutic effects in vivo similarly to polymyxin B but displayed much lower toxicity in vivo than polymyxin B. Taken together, the newly designed peptides (WRK)₄ and (WRK)₅ presented tremendous potential as novel antimicrobial candidates in response to the growing antimicrobial resistance.

Metabolic syndrome cannot mask the changes of faecal microbiota compositions caused by primary hepatocellular carcinoma

Both hepatocellular carcinoma (HCC) and metabolic syndrome are closely associated with the composition of the gut microbiota (GM). Although it has been proposed that elements of the GM can be used as biomarkers for the early diagnosis of HCC, whether metabolic syndrome results in a misrepresentation of the results of the early diagnosis of HCC using GM remains unclear. We compared the differences in the faecal microbiota of 10 patients with primary HCC, six patients with type 2 diabetes mellitus (T2DM), seven patients with arterial hypertension, six patients with both HCC and T2DM, and 10 patients with both HCC and arterial hypertension, as well as 10 healthy subjects, using high-throughput sequencing of 16S rRNA gene amplicons. Our results revealed a significant difference in the GM between subjects with and without HCC. The 49 bacterial genera out of the 494 detected genera were significantly different between the groups. These results show that changes in the GM can be used to distinguish between subjects with and without HCC, and can resist interference of T2DM and arterial hypertension with the GM. The results of the present study provide an important basis for the clinical auxiliary diagnosis of HCC by detecting the GM.

[The role of Artificial intelligent-based FFRCT in assessing the hemodynamic relevance of deep myocardial bridge of the left anterior descending coronary artery]

Objective: To investigate the role of artificial intelligence-based coronary CT blood flow reserve score (FFR_CT) in assessing hemodynamic relevance in patients with deep myocardial bridge (MB) of the left anterior descending coronary artery. Methods: A total of 113 patients diagnosed with deep MB of the left anterior descending coronary artery by coronary CT angiography (CCTA) at the Department of Radiology of Tongji Hospital Affiliated to Tongji University from January 2017 to December 2019 were retrospectively analyzed. The location, length, depth, and degree of systolic compression of the MB were measured. The artificial intelligence-based coronary FFR_CT software was employed to calculate the FFR_CT value of the deep MB of the left anterior descending coronary artery. With the boundary of 0.80, all patients were divided into FFR_CT normal group (FFR_CT>0.80) and FFR_CT abnormal group (FFR_CT≤0.80), and the relationship between FFR_CT abnormality and the location, length, depth, and degree of systolic stenosis of the deep MB of the left anterior descending branch was analyzed. The effectiveness of the receiver operating characteristic (ROC) curve in predicting FFR_CT abnormalities was measured by using ROC curve to analyze the length, depth, and degree of systolic stenosis of MB. Results: There were no significant differences in age, gender and high-risk factors between FFR_CT normal group (n=79) and FFR_CT abnormal group (n=34) (P>0.05). In terms of clinical symptoms, unstable angina, asymptomatic myocardial ischemia, stable angina in the FFR_CT normal group were 15.2%, 41.8%, 32.9%,respectively, while 32.4%, 23.5%, 35.3% in the FFR_CT abnormal group,respectively. Except for unstable angina (χ²=4.32,P=0.038), there were no significant differences in asymptomatic myocardial ischemia and stable angina between the two groups (χ²=3.42, 0.06, P>0.05). The length of deep MB was about (36±5) mm in the FFR_CT normal group and (44±5) mm in the FFR_CT abnormal group, respectively. The difference between the two groups was statistically significant (t=-7.703, P<0.001). The ROC curve showed that the optimal critical value of the length of the deep MB was 39.7 mm, the area under the curve was 0.88 (95%CI:0.81-0.95, P<0.001), and the accuracy rate of diagnosing FFR_CT ≤0.80 was 82.3%. Conclusion: FFR_CT value is of great value in the evaluation of hemodynamics in patients with deep myocardial bridge of left anterior descending coronary artery, and the length of deep myocardial bridge is an important factor affecting FFR_CT value.

[Present and future: artificial intelligence in medical imaging]

Artificial intelligence (AI) is a hot point in clinical medicine research. In recent years, AI has played an important role in recognizing the lesion, improving the diagnostic accuracy and assessing the diagnostic efficacy. To accelerate the pace of AI industry, it should be a first thing to improve relevant industrial policies and regulations and to build a transformation platform for industry-university-research. All these will contribute to the standardization in further development of medical imaging AI industry.

Antimicrobial peptides with symmetric structures against multidrug-resistant bacteria while alleviating antimicrobial resistance

In response to the dramatically increasing antimicrobial resistance, a series of new symmetric peptides were designed and synthesized in this study by a "WWW" motif as the symmetric center, arginine as the positive charge amino acid and the terminus symmetrically tagged with hydrophobic amino acids. Amongst the new symmetric peptide FRRW (FRRWWWRRF-NH₂) presented the highest cell selectivity for bacteria over mammalian cell and exerted excellent antimicrobial potential against a broad of bacteria, especially difficult-to-kill multidrug-resistant strains clinical isolates. FRRW also displayed perfect stability in physiological salt ions and rapid killing speed as well as acted on multiple mechanisms including non-receptor mediated membrane and intra-molecular mechanisms. Importantly, FRRW emerged a low tendency of resistance in contrast to traditional antibiotics ciprofloxacin and gentamicin. What's more, FRRW could resist or alleviate or even reverse the ciprofloxacin- and gentamicin-resistance by changing the permeability of bacterial membrane and inhibiting the efflux pumps of bacteria. Furthermore, FRRW exhibited remarkable effectiveness and higher safety in vivo than polymyxin B. In summary, the new symmetric peptide FRRW was promised to be as a new antimicrobial candidate for overcoming the increasing bacterial resistance.

New designed pH-responsive histidine-rich peptides with antitumor activity

Anticancer peptides have received widespread attention as alternative antitumor therapeutics due to their unique action mode. However, the systemic toxicity hampers their successful utilisation in tumour therapy. Here, the tumour acidic environment was used as a trigger to design a series of histidine-rich peptides by optimising the distribution of histidine and leucine based on the amphiphilic peptide LK, in hoping to achieve desirable acid-activate anticancer peptides. Among all the obtained peptides, L9H5-1 showed enhanced antitumor activity at acidic pH concomitant with low toxicity at normal pH, exhibiting excellent pH-response. At acidic pH, protonated L9H5-1 could rapidly kill tumour cells by efficient membrane disruption as evidenced by in vitro experiments, including increasing intracellular PI uptake and LDH release, dramatic membrane damage and increase of later apoptotic/necrotic cells. Moreover, no cell cycle arrest was observed after treated with L9H5-1. Interestingly, this study found that the new peptides with the same number of histidines and leucines displayed different pH-dependent antitumor activity, indicating that the position of amino acid alteration is extremely important for the design of acid-activated histidine-rich peptides. In short, our work provides a new avenue to develop new acid-activated anticancer peptides as promising antitumor drugs with high efficiency and good selectivity.

Predictive Value of Serum Creatinine/Cystatin C in Acute Ischemic Stroke Patients under Nutritional Intervention

BACKGROUND AND PURPOSE

As a very common risk of adverse outcomes of the ischemic stroke patients, sarcopenia is associated with infectious complications and higher mortality. The goal of this retrospective study is to explore the predictive value of serum Cr/CysC ratio in acute ischemic stroke patients receiving nutritional intervention.

METHODS

We reviewed adult patients with AIS from December 2019 to February 2020. Patients with acute kidney injury were excluded and all patients received nutritional intervention during a 3-month follow-up period. We collected baseline data at admission including creatinine and cystatin C. The primary poor outcome was major disability (modified Rankin Scale score ≥ 4) at 3 months after AIS.

RESULTS

A total of 217 patients with AIS were identified for this study. Serum Cr/CysC ratio was significantly correlated with NIHSS at discharge, 1-month modified Rankin Scale score, and 3-month modified Rankin Scale score. During 3 months, 34 (15.70%) patients had a poor outcome after AIS and 11 (5.10%) patients died within 30 days. In multivariable logistic regression analyses, serum Cr/CysC ratio at admission was independently associated with 3-month poor outcomes (OR: 0.953, 95% CI: 0.921-0.986, p = .006) and 30-day mortality (OR: 0.953, 95% CI: 0.921-0.986, p = .006).

CONCLUSION

As a blood biochemical indexes reflecting the muscle mass and aiding in risk stratification, Cr/CysC ratio at admission could be used as a predictor of 30-day mortality and long-term poor prognosis in AIS patients.

Ultra-short lipopeptides against gram-positive bacteria while alleviating antimicrobial resistance

Facing the continuously urgent demands for novel antimicrobial agents since the growing emergence of bacterial resistance, a series of new ultra-short lipopeptides, composed of tryptophan and arginine and fatty acids, were de novo designed and synthesized in this study. Most of the new lipopeptides exhibited preferable antimicrobial potential against gram-positive bacteria, including MRSA clinical isolates. Among them, the new lipopeptides C14-R1 (C14-RWW-NH₂) and C12-R2 (C12-RRW-NH₂) presented higher selectivity to bacterial membranes over mammalian membranes and low cytotoxicity, which also maintained better antimicrobial activity in the presence of physiological salts or serum. Most importantly, C14-R1 and C12-R2 not only expressed low tendency of bacterial resistance, but also displayed synergistic antimicrobial activity against antibiotics-resistant bacteria when be used in combination with antibiotics. Especially, they could alleviate or reverse the ciprofloxacin resistance, implying an ideal anti-resistance function. Moreover, the new lipopeptides showed rapid killing kinetics, obvious effectiveness for persistent cells that escaped from antibiotics, and strong anti-biofilm ability, which further indicated a preferable anti-resistance ability. The typical non-receptor-mediated membrane mechanisms were characterized by LPS/LTA competitive inhibition, cytoplasmic membrane depolarization, PI uptake assay and scanning electron microscopy analyses systematically. Reactive oxygen species (ROS) generation assays supplemented their intracellular targets in the meanwhile. In addition to the remarkable antimicrobial activity in vivo, the new lipopeptides also displayed significant anti-inflammatory effect in vivo. To sum up, the new lipopeptides C14-R1 and C12-R2 viewed as novel antimicrobial alternatives for tackling the impending crisis of antimicrobial resistance.

Yeast cell wall product enhanced intestinal IgA response and changed cecum microflora species after oral vaccination in chickens

The study was designed to explore the effect of a commercial yeast cell wall product (YP) on chicken intestinal IgA response and cecum microbiome after oral vaccination. Chickens were fed with YP during the experiments and orally immunized with live Newcastle disease virus (NDV) vaccine at 2 wk of age. Then, the animals were sacrificed, and samples were collected to measure the indicators of hemagglutination inhibition (HI), IgA response, IgA + cells, and cecum microbiome populations. The results showed that supplement of YP significantly enhanced serum NDV HI titer, intestinal NDV-specific secretory IgA, and intestinal IgA + cells. The sequencing results revealed that obviously increased relative abundance of Ruminococcaceae and decreased population of Bacteroidaceae in cecum were found in YP group. In summary, YP supplementation in diet enhanced intestinal IgA response to NDV vaccination by oral route and modulated the cecum microbiota to the advantage of the host in chickens.

A novel apoA-I mimetic peptide suppresses atherosclerosis by promoting physiological HDL function in apoE-/- mice

BACKGROUND AND PURPOSE

Apolipoprotein A-I (apoA-I) mimetic peptides (AAMPs) are short peptides that can mimic the physiological effects of apoA-I, including the suppression of atherosclerosis by reversely transporting peripheral cholesterol to the liver. As the hydrophobicity of apoA-I is considered important for its lipid transport, novel AAMPs were designed and synthesized in this study by gradually increasing the hydrophobicity of the parent peptide, and their anti-atherosclerotic effects were tested.

EXPERIMENTAL APPROACH

Seventeen new AAMPs (P1-P17) with incrementally increased hydrophobicity were designed and synthesized by replacing the amino acids 221-240 of apoA-I (VLESFKVSFLSALEEYTKKL). Their effects on cholesterol efflux were evaluated. Their cytotoxicity and haemolytic activity were also measured. The in vitro mechanism of the action of the new peptides was explored. Adult apolipoprotein E^-/- mice were used to evaluate the anti-atherosclerotic activity of the best candidate, and the mechanistic basis of its anti-atherosclerotic effects was explored.

KEY RESULTS

Seventeen new AAMPs (P1-P17) were synthesized, and their cholesterol efflux activity and cytotoxicity were closely related to their hydrophobicity. P12 (FLEKLKELLEHLKELLTKLL) was the best candidate and most strongly promoted cholesterol efflux among the non-toxic peptides (P1-P12). With its phospholipid affinity, P12 facilitated cholesterol transport through the ATP-binding cassette transporter A1. In vivo, P12 exhibited prominent anti-atherosclerotic activity via coupling with HDL.

CONCLUSION AND IMPLICATIONS

P12 featured adequate hydrophobicity, which ensured its efficient binding with cytomembrane phospholipids, cholesterol and HDL, and provided a basis for its ability to reversely transport cholesterol and treat atherosclerosis.