Derivatisation of buforin IIb, a cationic henicosapeptide, to afford its complexation to platinum(ii) resulting in a novel platinum(ii)-buforin IIb conjugate with anti-cancer activity

Antimicrobial peptides: An alternative to traditional antibiotics

As antibiotic-resistant bacteria and genes continue to emerge, the identification of effective alternatives to traditional antibiotics has become a pressing issue. Antimicrobial peptides are favored for their safety, low residue, and low resistance properties, and their unique antimicrobial mechanisms show significant potential in combating antibiotic resistance. However, the high production cost and weak activity of antimicrobial peptides limit their application. Moreover, traditional laboratory methods for identifying and designing new antimicrobial peptides are time-consuming and labor-intensive, hindering their development. Currently, novel technologies, such as artificial intelligence (AI) are being employed to develop and design new antimicrobial peptide resources, offering new opportunities for the advancement of antimicrobial peptides. This article summarizes the basic characteristics and antimicrobial mechanisms of antimicrobial peptides, as well as their advantages and limitations, and explores the application of AI in antimicrobial peptides prediction amd design. This highlights the crucial role of AI in enhancing the efficiency of antimicrobial peptide research and provides a reference for antimicrobial drug development.

Peptide cargo administration: current state and applications

Effective delivery of drug molecules to the target site is a challenging task. In the last decade, several innovations in the drug delivery system (DDS) have tremendously improved the therapeutic efficacy of drug molecules. Among various DDS, cell-penetrating peptides (CPPs) based DDS have gathered notable attention owing to their safety, efficacy, selectivity, specificity, and ease of synthesis. CPPs are emerging as an efficient and effective pharmaceutical nanocarriers-based platforms for successful management of various important human health disorders. Failure of several current chemotherapeutic strategies is attributed to low solubility, reduced bioavailability, and off-target delivery of several anti-cancer drugs. Similarly, development of therapeutics for vision-threatening disorders is challenged by the anatomical as well as physiological complexity of the eye. Such therapeutic challenges in cancer and ocular disease management can be overcome by developing cell-penetrating peptide (CPP) based peptide drug conjugates (PDCs). CPPs can be used to deliver various types of cargo molecules including nucleic acids, small molecules, and peptides/proteinaceous agents. In this review, we have briefly introduced CPPs and the linker strategies employed for the development of PDCs. Furthermore, recent studies employing CPP-based PDCs for cancer and ocular disease management have been discussed in detail highlighting their significance over conventional DDS. Later sections of the review are focused on the current status of clinical trials and future implications of CPP-based PDCs in vaccine development. KEY POINTS: • Cell-penetrating peptides (CPPs) can deliver a variety of cargo macromolecules via covalent and non-covalent conjugation. • CPP-based peptide drug conjugates (PDCs) can overcome drawbacks of conventional drug delivery methods such as biocompatibility, solubility, stability, and specificity. • Various PDCs are in clinical trial phase for cancer and ocular therapeutics.

Investigation on Optical and Biological Properties of 2-(4-Dimethylaminophenyl)benzothiazole Based Cycloplatinated Complexes

The optical and biological properties of 2-(4-dimethylaminophenyl)benzothiazole cycloplatinated complexes featuring bioactive ligands ([{Pt(Me2 N-pbt)(C6 F5 )}L] [L=Me2 N-pbtH 1, p-dpbH (4-(diphenylphosphino)benzoic acid) 2, o-dpbH (2-(diphenylphosphino)benzoic acid) 3), [Pt(Me2 N-pbt)(o-dpb)] 4, [{Pt(Me2 N-pbt)(C6 F5 )}2 (μ-PRn P)] [PR4 P=O(CH2 CH2 OC(O)C6 H4 PPh2 )2 5, PR12 P=O{(CH2 CH2 O)3 C(O)C6 H4 PPh2 }2 6] are presented. Complexes 1-6 display 1 ILCT and metal-perturbed 3 ILCT dual emissions. The ratio between both bands is excitation dependent, accomplishing warm-white emissions for 2, 5 and 6. The phosphorescent emission is lost in aerated solutions owing to photoinduced electron transfer to 3 O2 and the formation of 1 O2 , as confirmed in complexes 2 and 4. They also exhibit photoinduced phosphorescence enhancement in non-degassed DMSO due to local oxidation of DMSO by sensitized 1 O2 , which causes a local degassing. Me2 N-pbtH and the complexes specifically accumulate in the Golgi apparatus, although only 2, 3 and 6 were active against A549 and HeLa cancer cell lines, 6 being highly selective in respect to nontumoral cells. The potential photodynamic property of these complexes was demonstrated with complex 4.

A teleost bactericidal permeability-increasing protein-derived peptide that possesses a broad antibacterial spectrum and inhibits bacterial infection as well as human colon cancer cells growth

The bactericidal permeability-increasing protein (BPI) is a multifunctional cationic protein produced by neutrophils with antibacterial, antitumor, and LPS-neutralizing properties. In teleost, a number of BPIs have been reported, but their functions are very limited. In this study, an N-terminal peptide, BO18 (with 18 amino acids), derived from rock bream (Oplegnathus fasciatus) BPI, was synthesized and investigated for its antibacterial spectrum, action mechanism, immunoregulatory property as well as the inhibition effects on bacterial invasion and human colon cancer cells growth. The results showed that BO18 was active against Gram-positive bacteria Bscillus subiilis, Micrococcus luteus, and Staphylococcus aureus, as well as Gram-negative bacteria Vibrio alginolyticus, Vibrio litoralis, Vibrio parahaemolyticus and Vibrio vulnificus. BO18 treatment facilitated the bactericidal process of erythromycin and rifampicin by enhancing the permeability of the outer membrane. During its interaction with V. alginolyticus, BO18 exerted its antibacterial activity by destroying cell membrane integrity, penetrating into the cytoplasm and binding to genomic DNA and total RNA. In vitro analysis indicated BO18 could enhance the respiratory burst ability and regulate the expression of immune related genes of macrophages. In vivo detection showed the administration of fish with BO18 before bacterial infection significantly reduced pathogen dissemination and replication in tissues. In addition, BO18 exerted a cytotoxic effect on the growth of human colon cancer cells HT-29. Together, these results add new insights into the function of teleost BPIs, and support that BO18 is a novel and broad-spectrum antibacterial peptide with potential to apply in fighting pathogenic infection in aquaculture.

Recent Advances and Trends in Chemical CPP-Drug Conjugation Techniques

This review summarizes recent developments in conjugation techniques for the synthesis of cell-penetrating peptide (CPP)–drug conjugates targeting cancer cells. We will focus on small organic molecules as well as metal complexes that were used as cytostatic payloads. Moreover, two principle ways of coupling chemistry will be discussed direct conjugation as well as the use of bifunctional linkers. While direct conjugation of the drug to the CPP is still popular, the use of bifunctional linkers seems to gain increasing attention as it offers more advantages related to the linker chemistry. Thus, three main categories of linkers will be highlighted, forming either disulfide acid-sensitive or stimuli-sensitive bonds. All techniques will be thoroughly discussed by their pros and cons with the aim to help the reader in the choice of the optimal conjugation technique that might be used for the synthesis of a given CPP–drug conjugate

Toward Multi-Targeted Platinum and Ruthenium Drugs-A New Paradigm in Cancer Drug Treatment Regimens?

While medicinal inorganic chemistry has been practised for over 5000 years, it was not until the late 1800s when Alfred Werner published his ground-breaking research on coordination chemistry that we began to truly understand the nature of the coordination bond and the structures and stereochemistries of metal complexes. We can now readily manipulate and fine-tune their properties. This had led to a multitude of complexes with wide-ranging biomedical applications. This review will focus on the use and potential of metal complexes as important therapeutic agents for the treatment of cancer. With major advances in technologies and a deeper understanding of the human genome, we are now in a strong position to more fully understand carcinogenesis at a molecular level. We can now also rationally design and develop drug molecules that can either selectively enhance or disrupt key biological processes and, in doing so, optimize their therapeutic potential. This has heralded a new era in drug design in which we are moving from a single- toward a multitargeted approach. This approach lies at the very heart of medicinal inorganic chemistry. In this review, we have endeavored to showcase how a "multitargeted" approach to drug design has led to new families of metallodrugs which may not only reduce systemic toxicities associated with modern day chemotherapeutics but also address resistance issues that are plaguing many chemotherapeutic regimens. We have focused our attention on metallodrugs incorporating platinum and ruthenium ions given that complexes containing these metal ions are already in clinical use or have advanced to clinical trials as anticancer agents. The "multitargeted" complexes described herein not only target DNA but also contain either vectors to enable them to target cancer cells selectively and/or moieties that target enzymes, peptides, and intracellular proteins. Multitargeted complexes which have been designed to target the mitochondria or complexes inspired by natural product activity are also described. A summary of advances in this field over the past decade or so will be provided.

K, Kannoth Manheri M. Serine- and threonine-derived diamine equivalents for site-specific incorporation of platinum centers in peptides, and the anticancer potential of these conjugates

A modular strategy that gives access to a library of peptide–Pt conjugates and their anticancer potential is presented.

Research progress in modern structure of platinum complexes

Since the antitumor activity of cisplatin was discovered in 1967 by Rosenberg, platinum-based anticancer drugs have played an important role in chemotherapy in clinic. Nevertheless, platinum anticancer drugs also have caused severe side effects and cross drug resistance which limited their applications. Therefore, a significant amount of efforts have been devoted to developing new platinum-based anticancer agents with equal or higher antitumor activity but lower toxicity. Until now, a large number of platinum-based complexes have been prepared and extensively investigated in vitro and in vivo. Among them, some platinum-based complexes revealing excellent anticancer activity showed the potential to be developed as novel type of anticancer agents. In this account, we present such platinum-based anticancer complexes which owning various types of ligands, such as, amine carrier ligands, leaving groups, reactive molecule, steric hindrance groups, non-covalently binding platinum (II) complexes, Platinum(IV) complexes and polynuclear platinum complexes. Overall, platinum-based anticancer complexes reported recently years upon modern structure are emphasized.

Platinum(iv) oxaliplatin–peptide conjugates targeting memHsp70+ phenotype in colorectal cancer cells

Novel Pt(iv) tumour penetrating peptide (TPP) conjugates are reported.

Facile synthesis of highly biocompatible folic acid-functionalised SiO2nanoparticles encapsulating rare-earth metal complexes, and their application in targeted drug delivery

Herein, we report the facile synthesis of highly biocompatible folic acid-functionalized SiO₂nanoparticles encapsulating rare-earth metal complexes, and their application in targeted metal complex delivery.