Distinct chemical degradation pathways of AAV1 and AAV8 under thermal stress conditions revealed by analytical anion exchange chromatography and LC-MS-based peptide mapping.

Adeno-associated virus (AAV)-based gene therapy is experiencing a rapid growth in the field of medicine and holds great promise in combating a wide range of human diseases. For successful development of AAV-based products, comprehensive thermal stability studies are often required to establish storage conditions and shelf life. However, as a relatively new modality, limited studies have been reported to elucidate the chemical degradation pathways of AAV products under thermal stress conditions. In this study, we first presented an intriguing difference in charge profile shift between thermally stressed AAV8 and AAV1 capsids when analyzed by anion exchange chromatography. Subsequently, a novel and robust peptide mapping protocol was developed and applied to elucidate the underlying chemical degradation pathways of thermally stressed AAV8 and AAV1. Compared to the conventional therapeutic proteins, the unique structure of AAV capsids also led to some key differences in how modifications at specific sites may impact the overall charge properties. Finally, despite the high sequency identity, the analysis revealed that the opposite charge profile shifts between thermally stressed AAV8 and AAV1 could be mainly attributed to a single modification unique to each serotype.

A comprehensive LC-MS based study of factors influencing biotinylation of critical reagents.

Aim: Critical reagents (CR) are applied in ligand binding assays (LBA) and biotinylation is a widely conjugation method used for critical reagents. However, insufficient characterization and inconsistent biotinylation can lead to LBA failures and necessitate extensive troubleshooting. This publication developed the detection of biotinylated CR and evaluates efficiency of biotinylation conditions to ensure the reliability of reagents and accuracy when implemented in LBA.Materials & methods: Intact mass analysis was applied to characterize a CR with complex glycosylation and biotinylation patterns. Peptide mapping was developed to identify the biotinylation sites.Results: Biotinylation degrees and sites were clearly illustrated.Conclusion: A CR and its biotinylation were successfully characterized. The relationship between biotinylation efficiency and labeling conditions was clearly illustrated.

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Investigation of Dual-Loaded Doxorubicin and Sorafenib Liposomes Co-Modified with Glycyrrhetinic Acid and Cell-Penetrating Peptide TAT.

BACKGROUND: Combining Doxorubicin (DOX) with sorafenib (SF) is a promising strategy for treating Hepatocellular Carcinoma (HCC). However, strict dosage control is required for both drugs, and there is a lack of target selectivity. OBJECTIVE: This study aims to develop a novel nano-drug delivery system for the combined use of DOX and SF, aiming to reduce their respective dosages, enhance therapeutic efficacy, and improve target selectivity. METHODS: DOX/SF co-loaded liposomes (LPs) were prepared using the thin-film hydration method. The liposomes were modified with 1,2-distearoyl-sn-glycero-3-phospho-ethanolamine (DSPE)- polyethylene glycol (PEG2000), DSPE-PEG1000-cell penetrating peptide TAT, and Glycyrrhetinic Acid (GA). The basic properties of the liposomes were characterized. CCK-8 cell viability assays were conducted using HepG2, MHCC97-H, and PLC cell models, and apoptosis experiments were performed using HepG2 cells to determine if this delivery system could reduce the respective dosages of DOX and SF and enhance HCC cytotoxicity. Liposome uptake experiments were performed using HepG2 cells to validate the target selectivity of this delivery system. RESULTS: A GA/TAT-DOX/SF-LP liposomal nano drug delivery system was successfully constructed, with a particle size of 150 nm, a zeta potential of -7.9 mV, a DOX encapsulation efficiency of 92%, and an SF encapsulation efficiency of 88.7%. Cellular experiments demonstrated that this delivery system reduced the required dosages of DOX and SF, exhibited stronger cytotoxicity against liver cancer cells, and showed better target selectivity. CONCLUSION: A simple and referenceable liposomal nano drug delivery system has been developed for the combined application of DOX and SF in hepatocellular carcinoma treatment.

The Effect of Immobilization Methods of P9-4 Antimicrobial Peptide Onto Gelatin Methacrylate on Multidrug-Resistant Bacteria: A Comparative Study.

Wound dressings play a crucial role in wound management by providing a protective barrier and creating an optimal environment for healing. Photocrosslinkable hydrogels, such as gelatin methacrylate (GelMA), have gained attention for their unique properties but often lack antimicrobial activity. To enhance their effectiveness, researchers are exploring methods to incorporate antimicrobial agents into photocrosslinkable hydrogel dressings. Immobilization of antimicrobial peptides (AMPs) onto hydrogel matrices may be achieved through physical or chemical methods. Although, chemical immobilization, using techniques like EDC/NHS chemistry, has shown promise in enhancing antimicrobial properties of hydrogels, the capacity for immobilization may be limited by the structure of hydrogel. Physical methods, such as immersing, offer alternatives but may have different efficacy and biocompatibility. The study aims to chemically immobilize GelMA with P9-4 AMP by photoinduced conjugation and EDC/NHS chemistry and compare its antimicrobial efficacy with a physical immobilization method. Chemical immobilization by EDC/NHS chemistry significantly enhances the antimicrobial effect of GelMA hydrogels against multi-drug resistant Psuedomonas aeruginosa (MDR P. aeruginosa) and methicillin-resistant Staphylococcus aureus (MRSA) while maintaining favorable biocompatibility. Study highlights the potential of AMP-functionalized GelMA as advanced wound dressings for reducing infections caused by antibiotic-resistant bacteria and offers a promising approach for future research in wound management.

The effects of antimicrobial peptides buCaTHL4B and Im-4 on infectious root canal biofilms.

Purpose: The primary cause of pulp and periapical diseases is the invasion of bacteria into the root canal, which results from the continuous destruction of dental hard tissues. Effective management of infections during root canal therapy necessitates effectively irrigation. This study aims to investigate the effects of two antimicrobial peptides (AMPs), buCaTHL4B and Im-4, on root canal biofilms in vitro. Methods: Two-species biofilms (Enterococcus faecalis and Fusobacterium nucleatum) were selected and anaerobically cultivated. The following treatments were applied: 10 µg/mL buCaTHL4B, 10 µg/mL Im-4, 5 µg/mL buCaTHL4B, 5 µg/mL Im-4, 1 µg/mL buCaTHL4B, 1 µg/mL Im-4, 1% NaOCl, and sterile water. Each group was treated for 3 min. Subsequently, the two strains were co-cultured with 10 µg/mL buCaTHL4B, 10 µg/mL Im-4, 1% NaOCl, and sterile water for 24, 48, and 72 h. The biofilms were examined using confocal laser scanning microscopy (CLSM) with fluorescent staining, and the percentages of dead bacteria were calculated. Quantitative real-time PCR (qRT-PCR) was employed to assess the variations in bacterial proportions during biofilm formation. Results: Compared to 1% NaOCl, 10 µg/mL buCaTHL4B or Im-4 exhibited significantly greater bactericidal effects on the two-species biofilms (p < 0.05), leading to their selection for subsequent experiments. Over a 48-hour period, 10 µg/mL Im-4 demonstrated a stronger antibiofilm effect than buCaTHL4B (p < 0.05). Following a 24-hour biofilm formation period, the proportion of F. nucleatum decreased while the proportion of E. faecalis increased in the sterile water group. In the buCaTHL4B and 1% NaOCl groups, the proportion of F. nucleatum was lower than that of E. faecalis (p < 0.05), whereas in the Im-4 group, the proportion of F. nucleatum was higher than that of E. faecalis (p < 0.05). The proportions of bacteria in the two AMPs groups gradually stabilized after 24 h of treatment. Conclusion: buCaTHL4B and Im-4 exhibited remarkable antibacterial and anti-biofilm capabilities against pathogenic root canal biofilms in vitro, indicating their potential as promising additives to optimize the effectiveness of root canal treatment as alternative irrigants.

Team players in the pathogenesis of metabolic dysfunctions-associated steatotic liver disease: The basis of development of pharmacotherapy.

Nutrient metabolism is regulated by several factors. Social determinants of health with or without genetics are the primary regulator of metabolism, and an unhealthy lifestyle affects all modulators and mediators, leading to the adaptation and finally to the exhaustion of cellular functions. Hepatic steatosis is defined by presence of fat in more than 5% of hepatocytes. In hepatocytes, fat is stored as triglycerides in lipid droplet. Hepatic steatosis results from a combination of multiple intracellular processes. In a healthy individual nutrient metabolism is regulated at several steps. It ranges from the selection of nutrients in a grocery store to the last step of consumption of ATP as an energy or as a building block of a cell as structural component. Several hormones, peptides, and genes have been described that participate in nutrient metabolism. Several enzymes participate in each nutrient metabolism as described above from ingestion to generation of ATP. As of now several publications have revealed very intricate regulation of nutrient metabolism, where most of the regulatory factors are tied to each other bidirectionally, making it difficult to comprehend chronological sequence of events. Insulin hormone is the primary regulator of all nutrients' metabolism both in prandial and fasting states. Insulin exerts its effects directly and indirectly on enzymes involved in the three main cellular function processes; metabolic, inflammation and repair, and cell growth and regeneration. Final regulators that control the enzymatic functions through stimulation or suppression of a cell are nuclear receptors in especially farnesoid X receptor and peroxisome proliferator-activated receptor/RXR ligands, adiponectin, leptin, and adiponutrin. Insulin hormone has direct effect on these final modulators. Whereas blood glucose level, serum lipids, incretin hormones, bile acids in conjunction with microbiota are intermediary modulators which are controlled by lifestyle. The purpose of this review is to overview the key players in the pathogenesis of metabolic dysfunction-associated steatotic liver disease (MASLD) that help us understand the disease natural course, risk stratification, role of lifestyle and pharmacotherapy in each individual patient with MASLD to achieve personalized care and target the practice of precision medicine. PubMed and Google Scholar databases were used to identify publication related to metabolism of carbohydrate and fat in states of health and disease states; MASLD, cardiovascular disease and cancer. More than 1000 publications including original research and review papers were reviewed.

Encoding and display technologies for combinatorial libraries in drug discovery: The coming of age from biology to therapy.

Drug discovery is a sophisticated process that incorporates scientific innovations and cutting-edge technologies. Compared to traditional bioactivity-based screening methods, encoding and display technologies for combinatorial libraries have recently advanced from proof-of-principle experiments to promising tools for pharmaceutical hit discovery due to their high screening efficiency, throughput, and resource minimization. This review systematically summarizes the development history, typology, and prospective applications of encoding and displayed technologies, including phage display, ribosomal display, mRNA display, yeast cell display, one-bead one-compound, DNA-encoded, peptide nucleic acid-encoded, and new peptide-encoded technologies, and examples of preclinical and clinical translation. We discuss the progress of novel targeted therapeutic agents, covering a spectrum from small-molecule inhibitors and nonpeptidic macrocycles to linear, monocyclic, and bicyclic peptides, in addition to antibodies. We also address the pending challenges and future prospects of drug discovery, including the size of screening libraries, advantages and disadvantages of the technology, clinical translational potential, and market space. This review is intended to establish a comprehensive high-throughput drug discovery strategy for scientific researchers and clinical drug developers.

Hesperidin activates the GLP-1R/cAMP-CREB/IRS2/PDX1 pathway to promote transdifferentiation of islet α cells into ß cells Across the spectrum.

Background and aims: In all age, FoShou as a Chinese medicinal herb has been active in various kinds of Traditional Chinese medicine formula to treating diabetes. Hesperidin (HES), the main monomeric component of FoShou, has been extensively investigated for interventions with pathogenic mechanism of diabetes as well as subsequent treatment of associated complications. Islet ß-cells have an essential effect on dynamically regulating blood sugar. Functional abnormalities in these cells and their death are strongly associated with the onset of diabetes. Therefore, induction of islet endocrine cell lineage re-editing for damaged ßcell replenishment would be a promising therapeutic tool. Previously, it has been found that HES can protect islet ß-cells in vivo, But, the regenerative function of HES in islet ß cells and its role in promoting differential non-ß cells transdifferentiation into ß cells and cell fate rewriting associated mechanisms remain unclear.This work focused on investigating whether HES can induce islet α cells transdifferentiation into ß cells for achieving damaged ß cell regeneration and the causes and possible mechanisms involved in the process. Materials and methods: In brief, 60 mg/kg/d streptozotocin (STZ) was administered intraperitoneally in each male C57bL/6J mouse raised by the high-sugar and high-fat diet (HFD) to create a diabetic mouse model with severe ß-cell damage. After 28 consecutive days of HES treatment (160 mg/kg; 320 mg/kg; once daily, as appropriate). Tracing the dynamics of α as well as ß cell transformation, together with ß cells growth and apoptosis levels during treatment by cell lineage tracing. The self-enforcing transcriptional network on which the cell lineage is based is used as a clue to explore the underlying mechanisms. Guangdong Pharmaceutical University's Animal Experiment Ethics Committee (GDPulac2019180) approved all animal experiments. Results: Localization by cell lineage we find that transdifferentiated newborn ß-cells derived from α cells appeared in the islet endocrine cell mass of DM mice under HES'action. Compared to the model group, expressed by Tunel staining and CXCL10 levels the overall apoptosis rate of ß-cells of the pancreas were reduced,the inflammatory infiltration feedback from HE staining were lower.Ki-67 positive cells showed enhanced ß-cell proliferation. Decreased HbA1c and blood glucose contents, elevated C-Peptide and insulin contents which respond to ability of nascent beta cells. Also upregulated the mRNA levels of MafA, Ngn3, PDX-1, Pax4 and Arx. Moreover, increased the expression of TGR5/cAMP-CREB/GLP-1 in mouse intestinal tissues and GLP-1/GLP-1R and cAMP-CREB/IRS2/PDX-1 in pancreatic tissues. Conclusions: HES directly affects ß-cells, apart from being anti-apoptotic and reducing inflammatory infiltration. HES promotes GLP-1 release by intestinal L cells by activating the TGR5 receptor in DM mouse and regulating its response element CREB signaling. GLP-1 then uses the GLP-1/GLP-1R system to act on IRS2, IRS2 as a port to influence α precursor cells to express PDX-1, with the mobilization of Pax4 strong expression than Arx so that α cell lineage is finally reversed for achieving ß cell endogenous proliferation.

Novel multidomain peptide self-assembly biomaterials based on bola structure and terminal anchoring: Nanotechnology meets antimicrobial therapy.

To ameliorate the diminished antimicrobial efficiency and physiological stability associated with monomeric antimicrobial peptides (AMPs) molecules, future research will focus on the artificial design of self-assembling peptides to replace monomeric entities, aiming to combat the antibiotic resistance crisis caused by microbial infections. In this study, the "bola" structure was used as the foundational architecture driving molecular self-assembly, with hydrophobic amino acids at the termini to anchor and finely adjust the sequence, thereby organizing a range of novel multidomain peptides (MDPs) templates into an ABA block motif. The results indicate that FW2 (GMSI = 53.94) exhibits the highest selectivity index among all MDPs and can form spherical micelles in an aqueous medium without the addition of any exogenous additives. FW2 exhibited high stability in vitro in the presence of physiological salt ions, serum, and various pH conditions. It exhibited excellent biocompatibility and efficacy both in vivo and in vitro. Furthermore, FW2 strongly interacts with the lipid membrane and employs various synergistic mechanisms, such as reactive oxygen species (ROS) accumulation, collectively driving cellular apoptosis. This study demonstrates a straightforward strategy for designing self-assembling peptides and promotes the advancement of peptide-based biomaterials integration progress with nanotechnology.

Advances in lasso peptide discovery, biosynthesis, and function.

Lasso peptides are a large and sequence-diverse class of ribosomally synthesized and post-translationally modified peptide (RiPP) natural products characterized by their slip knot-like shape. These unique, highly stable peptides are produced by bacteria for various purposes. Their stability and sequence diversity make them a potentially useful scaffold for biomedically relevant folded peptides. However, many questions remain about lasso peptide biosynthesis, ecological function, and diversification potential for biomedical and agricultural applications. This review discusses new insights and open questions about lasso peptide biosynthesis and biological function. The role that genome mining has played in the development of new methodologies for discovering and diversifying lasso peptides is also discussed.

Stability in human serum and plasma of the HIV peptide drug candidate CIGB-210 and improved variants.

The peptide CIGB-210 inhibits HIV replication, inducing a rearrangement of vimentin intermediate filaments. The assessment of the in vitro serum and plasma stability of this peptide is important to develop an optimal pharmacological formulation. A half-life of 17.68 ± 0.59 min was calculated for CIGB-210 in human serum by reverse-phase high-performance liquid chromatography (HPLC) and mass spectrometry (MS). Eight metabolites of CIGB-210 were identified with this methodology, all of them lacking the N-terminal moiety. A previously developed CIGB-210 in-house competitive ELISA was used to compare the stability of CIGB-210 derivatives containing either D-amino acids, acetylation at the N-terminus, or both modifications. The half-life of CIGB-210 in serum was five times higher when measured by ELISA than by HPLC/MS, and twice higher in plasma as compared to serum. The substitution of D-asparagine on position 6 doubled the half-life, while D-amino acids on positions 8 and 9 did not improve the stability. The acetylation of the N-terminus resulted in a 24-fold more stable peptide in plasma. The positive effect of N-terminal acetylation on CIGB-210 serum stability was confirmed by the HPLC/MS method, as the half-life of the peptide was not reached after 2 h of incubation, which represents more than a 6.8-fold increase in the half-life with respect to the original peptide.

Effects of fremanezumab on migraine-associated symptoms and medication use in Japanese and Korean patients with episodic migraine: Exploratory endpoint analysis of a multicenter, randomized, double-blind, placebo-controlled trial.

OBJECTIVE: To describe exploratory endpoints from a previous phase 2b/3 placebo-controlled trial conducted in Japan and Korea, specifically investigating the effect of fremanezumab or placebo on migraine-associated symptoms and acute headache medication use in patients with episodic migraine (EM). BACKGROUND: EM is associated with non-head pain symptoms, including nausea, vomiting, photophobia, or phonophobia, which contribute substantially to the disease burden, healthcare resource utilization, and impaired quality of life. Current EM treatments include a mix of nonspecific/migraine-specific acute headache medications, but medication overuse can induce headaches and progression from EM to chronic migraine (CM). In multiple phase 2b/3 trials, the monoclonal antibody fremanezumab significantly reduced the average number of monthly migraine days experienced by patients with EM/CM compared with placebo. METHODS: This was a prespecified analysis of exploratory endpoints in a multicenter, randomized, double-blind, placebo-controlled, phase 2b/3 trial conducted in Japanese and Korean patients with EM (NCT03303092). Patients were randomized to receive fremanezumab, either monthly or quarterly, or matching placebo, administered subcutaneously at 4-week/28-day ("monthly") intervals to maintain blinding. Exploratory endpoints reported here were the mean change from baseline in the number of days/month with (i) the use of any acute headache medication, (ii) the use of any migraine-specific acute headache medication, (iii) nausea or vomiting, and (iv) photophobia and phonophobia. RESULTS: Overall, 357 Japanese and Korean patients with EM received either monthly (n = 121) or quarterly (n = 119) fremanezumab or placebo (n = 117). Compared with placebo, fremanezumab administered monthly or quarterly was associated with a significant reduction from baseline in the average number of days/month with acute headache medication use over three months (difference vs. placebo -2.81 [95% confidence interval (CI) -3.52, -2.11]; p < 0.001 and -2.79 [95% CI -3.50, -2.08]; p < 0.001, respectively). Similar findings were observed in the monthly average number of days with migraine-specific acute headache medications (difference vs. placebo with monthly and quarterly fremanezumab, -2.63 [95% CI -3.31, -1.95] for both; p < 0.001), the average number of days/month with nausea or vomiting (difference vs. placebo -1.09 [95% CI -1.60, -0.58]; p < 0.001 for monthly fremanezumab and -1.37 [95% CI -1.88, -0.86]; p < 0.001 for quarterly fremanezumab), and the average number of days with photophobia and phonophobia (difference vs. placebo -1.22 [95% CI -1.80, -0.65]; p < 0.001 and -1.64 [95% CI -2.22, -1.06]; p < 0.001, respectively). CONCLUSION: Monthly and quarterly administered fremanezumab effectively prevented EM in Japanese and Korean patients. Fremanezumab also improved other disease aspects including the need for acute headache medications and the frequency of migraine-associated symptoms.

Peptide retention time prediction for hydrophilic interaction liquid chromatography at acidic pH in formic-acid based eluents.

Peptide separation selectivity was evaluated for hydrophilic interaction liquid chromatography (HILIC) ZIC-HILIC, ZIC-cHILIC, and XBridge Amide sorbents using formic acid as eluent additive (pH 2.7). Sequence-specific retention prediction algorithms were trained using retention datasets of ∼30,000 peptides for each column. Our retention models were able to attain ∼0.98 R2-value and yielded retention coefficients that can be probed to understand peptide-stationary phase interaction. Overall, the hydrophilicity for these columns decreased when the mobile phase changed pH from 4.5 to 2.7, when using 0.1 % formic acid in the mobile phase. The acidic residues became protonated, and the resultant hydrophilic interaction is dampened at the lower pH, leaving only the basic residues as the primary hydrophilic interactors. Hence, peptides of increasing charge have higher retention. In this comparison between the three columns, ZIC-HILIC has the highest chromatographic resolution between groups of peptides of different charge. From the position-dependent retention coefficients for ZIC-HILIC at pH 2.7, we found that the amino acids at the terminal positions of the peptide modulate the basicity of the N-terminal amino group or the C-terminal Arg/Lys for tryptic peptides. With respect to the separation orthogonality between HILIC and acidic pH RPLC for two dimensional separations, the orthogonality values were lower at pH 2.7 than operating HILIC at pH 4.5 for the first dimension. We also demonstrate that ZIC-HILIC was able to distinguish citrullinated and deamidated peptides based on predicted retention values.

Can cerebrospinal fluid biomarkers tell us something about financial capacity in Alzheimer's disease patients? A preliminary study.

BACKGROUND: Although diagnostic markers in cerebrospinal fluid (CSF) have become a rapidly growing research field, they have not as yet been investigated in relation to capacities that are of interest to geriatric psychiatry and neuropsychology, such as financial capacity. The aim of this study was to assess whether CSF biomarkers can predict financial capacity in patients with a diagnosis of major neurocognitive disorder due to Alzheimer's disease (AD). METHODS: Participants were examined with a number of neuropsychological tests, with an emphasis on the Mini-Mental State Examination (MMSE), the Geriatric Depression Scale (GDS-15), and the Legal Capacity for Property Law Transactions Assessment Scale (LCPLTAS) and CSF tests. RESULTS: Amyloid ß peptide 1-42 (Aß42), total tau, and phosphorylated tau were not found to predict financial capacity performance in AD, but MMSE shows a strong positive correlation with LCPLTAS. CONCLUSIONS: These preliminary findings indicate that complex cognitive functions, such as financial capacity, may not be directly linked to CSF concentrations of the abovementioned biomarkers. Further studies with larger numbers of patients will be required to assess the reproducibility of these findings and to determine whether this approach can assist not only in diagnosis but also in neuropsychological assessment.

Combination of the amide-to-triazole substitution strategy with alternative structural modifications for the metabolic stabilization of tumor-targeting, radiolabeled peptides.

Radiolabeled peptides play a key role in nuclear medicine to selectively deliver radionuclides to malignancies for diagnosis (imaging) and therapy. Yet, their efficiency is often compromised by low metabolic stability. The use of 1,4-disubstituted 1,2,3-triazoles (1,4-Tzs) as stable amide bond bioisosteres can increase the half-life of peptides in vivo while maintaining their biological properties. Previously, the amide-to-triazole substitution strategy was used for the stabilization of the pansomatostatin radioligand [111In]In-AT2S, resulting in the mono-triazolo-peptidomimetic [111In]In-XG1, a radiotracer with moderately enhanced stability in vivo and retained ability to bind multiple somatostatin receptor (SSTR) subtypes. However, inclusion of additional 1,4-Tz led to a loss of affinity towards SST2R, the receptor overexpressed by most SSTR-positive cancers. To enhance further the stability of [111In]In-XG1, alternative modifications at the enzymatically labile position Thr10-Phe11 were employed. Three novel 1,4,7,10-tetraazacyclododecane-1,4,7,10-tetraacetic acid (DOTA)-peptide conjugates were synthesized with a 1,4-Tz (Asn5-Ψ[Tz]-Phe6) and either a ß-amino acid (ß-Phe11), reduced amide bond (Thr10-Ψ[NH]-Phe11), or N-methylated amino acid (N-Me-Phe11). Two of the new peptidomimetics were more stable in blood plasma in vitro than [111In]In-XG1. Yet none of them retained high affinity towards SST2R. We demonstrate for the first time the combination of the amide-to-triazole substitution strategy with alternative stabilization methods to improve the metabolic stability of tumor-targeting peptides.

Nesfatin-1 is a regulator of inflammation with implications during obesity and metabolic syndrome.

Nesfatin-1, derived from the nucleobindin 2 (NUCB2) precursor, is a potent anorexigenic peptide that was discovered in 2006. Since its identification in the hypothalamus, it has been shown to have wide ranging actions within and outside of the central nervous system. One of these actions is the regulation of inflammation, which could potentially be exploited therapeutically in the context of obesity-associated inflammation in adipose tissue. Here, we review recent advances in our knowledge about the ability of nesfatin-1 to control inflammation by regulating NFκB signaling, which likely attenuates pro-inflammatory cytokine production and inhibits apoptosis.

Morphological study of remineralization of the eroded enamel lesions by tyrosine-rich amelogenin peptide.

BACKGROUND: Tyrosine-rich amelogenin peptide (TRAP) is the main amelogenin digestion product in the developmental enamel matrix. It has been shown to promote remineralization of demineralized enamel in our previous study. However, direct evidence of the effect of TRAP on the morphology and nanostructure of crystal growth on an enamel surface has not been reported. This study aimed to examine the effect of TRAP on the morphology of calcium phosphate crystals grown on early enamel erosion using a pH-cycling model. METHODS: Eroded lesions were produced in human premolars by 30-second immersion in 37% phosphoric acid. Forty-five samples of eroded human premolar enamel blocks were selected and randomly divided into 3 groups: deionized water (DDW, negative control); 100 µg/mL TRAP, and 2 ppm sodium fluoride (NaF, positive control group). For 14 days, the specimens were exposed to a pH-cycling model. Using scanning electron microscopy (SEM) and atomic force microscopy (AFM) methods, the surface morphology, calcium-phosphorus ratio, and enamel surface roughness were examined. X-ray diffraction (XRD) and Fourier transform infrared spectroscopy (FT-IR) were used to assess crystal characteristics. RESULTS: After pH-cycling, compared to the two control groups, the surface of the eroded enamel of the peptide TRAP group shows a large number of new, densely arranged rod-like crystals, parallel to each other, regularly arranged, forming an ordered structure, with crystal morphology similar to that of natural enamel. The crystals are mostly hydroxyapatite (HA). CONCLUSION: This study demonstrates that the peptide TRAP modulates the formation of hydroxyapatite in eroded enamel and that the newly formed crystals resemble natural enamel crystals and promote the remineralization of enamel, providing a promising biomaterial for remineralization treatment of enamel lesions.

Potential of Fasting C-peptide to Glucose Ratio and Triglyceride Glucose Index as Markers for ß-Cell Dysfunction and Insulin Resistance in Patients With Type 2 Diabetes on Insulin Therapy.

BACKGROUND: Pathogenesis of type 2 diabetes mellitus (T2DM) is combined from initial insulin resistance (IR) and subsequent ß-cell dysfunction. Insulin therapy can replace ß-cell function in advanced stages. However excessive insulin therapy increases IR and may expose the patients to risk of cardiovascular disease. We aim to assess ß-cell function and IR in patients with type 2 diabetes on insulin therapy by fasting C-peptide to glucose ratio (FCPGR), and triglyceride glucose (TyG) index respectively to support treatment plans. METHOD: A cross-sectional study was conducted at the Galiawa Diabetes and Endocrinology Teaching Center in Erbil City, Iraq, from June 2023 to January 2024. A convenient sample of 100 patients with T2DM on insulin-based therapy were included after obtaining informed written consent and excluding conditions such as acute illness, uncertain type of diabetes, etc. Each patient was evaluated for anthropometric parameters and current treatment details. Biochemical tests were then carried out to calculate metabolic syndrome (MetS) index score, FCPGR, and TyG index. Finally, patients were divided into four subgroups according to their FCPGR and TyG index and the data were analyzed statistically. RESULT: The data showed those patients with sufficient ß-cell function were 60 (60%), and patients with high TyG index were 95 (95%). There was a significant negative correlation between FCPGR and hemoglobin A1c (HbA1c) (p-value=0.001), while there was a positive correlation between TyG index and HbA1C (p-value=0.001). None of these markers were correlated with BMI (p-value=0.297, and 0.976), duration of T2DM (p-value=0.258, and 0.458), and dose of insulin therapy (p-value=0.901, and 0.477). Patients with sufficient ß-cell function and high TyG index had the lowest HbA1C. CONCLUSION: The study provides valuable insights into the utility of FCPGR and TyG index as biomarkers for ß-cell function and insulin resistance in T2DM patients on insulin therapy. The significant correlation with HbA1C underscores their potential in clinical practice. However, the lack of correlation with BMI, disease duration, and insulin dose suggests that further investigation is needed to fully understand these biomarkers' implications across diverse patient profiles.

Intracellular bactericidal activity and action mechanism of MDP1 antimicrobial peptide against VRSA and MRSA in human endothelial cells.

Introduction: Staphylococcus aureus is a prominent cause of postoperative infections, often persisting within host cells, leading to chronic infections. Conventional antibiotics struggle to eliminate intracellular S. aureus due to poor cell penetration. Antimicrobial peptides are a new hope for tackling intracellular bacteria. Accordingly, this study examines the antimicrobial peptide MDP1, derived from melittin, for its efficacy against intracellular S. aureus. Methods: In this study, the physiochemical properties (Prediction of three-dimensional structure, circular dichroism and helical wheel projection analysis) were investigated. Extracellular antibacterial activity and cytotoxicity of MDP1 were also assessed. The mechanism of interaction of MDP1 with S. aureus was evaluated by molecular dynamic simulation, atomic force and confocal microscopy. Bacterial internalization into an endothelial cell model was confirmed through culture and transmission electron microscopy. The effect of the peptide on intracellular bacteria was investigated by culture and epi-fluorescence microscopy. Results and discussion: 3D structural prediction proved the conformation of MDP1 as an α-helix peptide. Helical-wheel projection analysis indicated the proper orientation of hydrophobic amino acid residues for membrane interaction. CD spectroscopy of MDP1 showed that MDP1 in SDS 10 and 30 mM adopted 87 and 91% helical conformation. Atomic force and confocal microscopy assessments as well as molecular dynamics studies revealed the peptide-bacterial membrane interaction. MDP1, at the concentration of 0.32 µg mL-1, demonstrated a fold reduction of 21.7 ± 1.8, 1.7 ± 0.2, and 7.3 ± 0.8 in intracellular bacterial load for ATCC, VRSA, and MRSA, respectively. Molecular dynamics results demonstrate a preferential interaction of MDP1 with POPG/POPE membranes, primarily driven by electrostatic forces and hydrogen bonding. In POPC systems, two out of four MDP1 interacted effectively, while all four MDP1 engaged with POPG/POPE membranes. Gathering all data together, MDP1 is efficacious in the reduction of intracellular VRSA and MRSA proved by culture and epi-fluorescent microscopy although further studies should be performed to increase the intracellular activity of MDP1.

iVAC-XS15-CLL01: personalized multi-peptide vaccination in combination with the TLR1/2 ligand XS15 in CLL patients undergoing BTK-inhibitor-based regimens.

Chronic lymphocytic leukemia (CLL) is the most common form of leukemia among adults in Western countries. Despite the introduction of targeted therapies, including first-line Bruton's tyrosine kinase inhibitor (BTKi) treatment, CLL remains largely incurable. Frequent disease relapses occur due to remaining treatment-resistant CLL cells, calling for novel therapies to eliminate minimal residual disease (MRD). Peptide-based vaccination targeting human leucocyte antigen (HLA)-presented CLL-associated antigens represents a promising, low-side-effect therapeutic option to optimize treatment responses and eliminate residual tumor cells by inducing an anti-leukemic immune response. The iVAC-XS15-CLL01 trial is an open-label, first-in-human (FIH) Phase I trial, evaluating the CLL-VAC-XS15 vaccine in CLL patients undergoing BTKi-based therapy. The vaccine was developed from HLA-presented CLL-associated antigen peptides, identified through comparative mass-spectrometry-based immunopeptidome analyses of CLL versus healthy samples in a previous study. To facilitate rapid and cost-effective deployment, vaccine peptides are selected for each patient from a pre-manufactured "peptide warehouse" based on the patient's individual HLA allotype and CLL immunopeptidome. The trial enrolls 20 CLL patients, who receive up to three doses of the vaccine, adjuvanted with the toll-like-receptor (TLR) 1/2 ligand XS15 and emulsified in Montanide ISA 51 VG. The primary objective of the iVAC-XS15-CLL01 trial is to assess the safety and immunogenicity of the CLL-VAC-XS15 vaccine. Secondary objectives are to evaluate the vaccine impact on MRD, progression-free survival, and overall survival, as well as comprehensive immunophenotyping to characterize vaccine-induced T-cell responses. This Phase I trial aims to advance CLL treatment by enhancing immune-mediated disease clearance and guiding the design of subsequent Phase II/III trials to implement a new therapeutic strategy for CLL patients.