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Brain Communications 2022Studies have correlated excessive S100B, a small inflammatory molecule, with demyelination and associated inflammatory processes occurring in multiple sclerosis. The...
Studies have correlated excessive S100B, a small inflammatory molecule, with demyelination and associated inflammatory processes occurring in multiple sclerosis. The relevance of S100B in multiple sclerosis pathology brought an emerging curiosity highlighting its use as a potential therapeutic target to reduce damage during the multiple sclerosis course, namely during inflammatory relapses. We examined the relevance of S100B and further investigated the potential of S100B-neutralizing small-molecule pentamidine in chronic experimental autoimmune encephalomyelitis. S100B depletion had beneficial pathological outcomes and based on promising results of a variety of S100B blockade strategies in an demyelinating model, we choose pentamidine to assay its role in the experimental autoimmune encephalomyelitis. We report that pentamidine prevents more aggressive clinical symptoms and improves recovery of chronic experimental autoimmune encephalomyelitis. Blockade of S100B by pentamidine protects against oligodendrogenesis impairment and neuroinflammation by reducing astrocyte reactivity and microglia pro-inflammatory phenotype. Pentamidine also increased regulatory T cell density in the spinal cord suggesting an additional immunomodulatory action. These results showed the relevance of S100B as a main driver of neuroinflammation in experimental autoimmune encephalomyelitis and identified an uncharacterized mode of action of pentamidine, strengthening the possibility to use this drug as an anti-inflammatory and remyelinating therapy for progressive multiple sclerosis.
PubMed: 35620168
DOI: 10.1093/braincomms/fcac076 -
Journal of Orthopaedic Translation Mar 2024Prevention of adhesion formation following flexor tendon repair is essential for restoration of normal finger function. Although many medications have been studied in...
BACKGROUND
Prevention of adhesion formation following flexor tendon repair is essential for restoration of normal finger function. Although many medications have been studied in the experimental setting to prevent adhesions, clinical application is limited due to the complexity of application and delivery in clinical translation.
METHODS
In this study, optimal dosages of gelatin and pentamidine were validated by gelatin concentration test. Following cell viability, cell migration, live and dead cell, and cell adhesion assay of the Turkey tenocytes, a model of Turkey tendon repair was established to evaluate the effectiveness of the Pentamidine-Gelatin sheet.
RESULTS
Pentamidine carried with gelatin, a Food and drug administration (FDA) approved material for drug delivery, showed good dynamic release, biocompatibility, and degradation. The optimal dose of pentamidine (25ug) was determined in the in vivo study using tenocyte viability, migration, and cell adhesion assays. Further biochemical analyses demonstrated that this positive effect may be due to pentamidine downregulating the Wnt signaling pathway without affecting collagen expression.
CONCLUSIONS
We tested a FDA-approved antibiotic, pentamidine, for reducing adhesion formation after flexor tendon repair in both in vitro and in vivo using a novel turkey animal model. Compared with the non-pentamidine treatment group, pentamidine treated turkeys had significantly reduced adhesions and improved digit function after six weeks of tendon healing.
THE TRANSLATIONAL POTENTIAL OF THIS ARTICLE
This study for the first time showed that a common clinical drug, pentamidine, has a potential for clinical application to reduce tendon adhesions and improve tendon gliding function without interfering with tendon healing.
PubMed: 38511123
DOI: 10.1016/j.jot.2023.10.007 -
Pathogens (Basel, Switzerland) May 2023Leishmaniasis, a category 1 neglected protozoan disease caused by a kinetoplastid pathogen called is transmitted through dipteran insect vectors (phlebotomine, sand... (Review)
Review
Leishmaniasis, a category 1 neglected protozoan disease caused by a kinetoplastid pathogen called is transmitted through dipteran insect vectors (phlebotomine, sand flies) in three main clinical forms: fatal visceral leishmaniasis, self-healing cutaneous leishmaniasis, and mucocutaneous leishmaniasis. Generic pentavalent antimonials have long been the drug of choice against leishmaniasis; however, their success is plagued with limitations such as drug resistance and severe side effects, which makes them redundant as frontline therapy for endemic visceral leishmaniasis. Alternative therapeutic regimens based on amphotericin B, miltefosine, and paromomycin have also been approved. Due to the unavailability of human vaccines, first-line chemotherapies such as pentavalent antimonials, pentamidine, and amphotericin B are the only options to treat infected individuals. The higher toxicity, adverse effects, and perceived cost of these pharmaceutics, coupled with the emergence of parasite resistance and disease relapse, makes it urgent to identify new, rationalized drug targets for the improvement in disease management and palliative care for patients. This has become an emergent need and more relevant due to the lack of information on validated molecular resistance markers for the monitoring and surveillance of changes in drug sensitivity and resistance. The present study reviewed the recent advances in chemotherapeutic regimens by targeting novel drugs using several strategies including bioinformatics to gain new insight into leishmaniasis. has unique enzymes and biochemical pathways that are distinct from those of its mammalian hosts. In light of the limited number of available antileishmanial drugs, the identification of novel drug targets and studying the molecular and cellular aspects of these drugs in the parasite and its host is critical to design specific inhibitors targeting and controlling the parasite. The biochemical characterization of unique -specific enzymes can be used as tools to read through possible drug targets. In this review, we discuss relevant metabolic pathways and novel drugs that are unique, essential, and linked to the survival of the parasite based on bioinformatics and cellular and biochemical analyses.
PubMed: 37242374
DOI: 10.3390/pathogens12050706 -
Drug Delivery Dec 2023Topical drug delivery is preferable route over systemic delivery in case of (CL). Among the available agents, amphotericin B (AmB) and pentamidine (PTM) showed...
Topical drug delivery is preferable route over systemic delivery in case of (CL). Among the available agents, amphotericin B (AmB) and pentamidine (PTM) showed promising result against CL. However, monotherapy is associated with incidences of reoccurrence and resistance. Combination therapy is therefore recommended. Thin film hydration method was employed for amphotericin B-pentamidine loaded niosomes (AmB-PTM-NIO) preparation followed by their incorporation into chitosan gel. The optimization of AmB-PTM-NIO was done via Box Behnken Design method and in vitro and ex vivo analysis was performed. The optimized formulation indicated 226 nm particle size (PS) with spherical morphology, 0.173 polydispersity index (PDI), -36 mV zeta potential (ZP) and with entrapment efficiency (EE) of 91% (AmB) and 79% (PTM), respectively. The amphotericin B-pentamidine loaded niosomal gel (AmB-PTM-NIO-Gel) showed desirable characteristics including physicochemical properties, pH (5.1 ± 0.15), viscosity (31870 ± 25 cP), and gel spreadability (280 ± 26.46%). In vitro release of the AmB and PTM from AmB-PTM-NIO and AmB-PTM-NIO-Gel showed more prolonged release behavior as compared to their respective drug solution. Higher skin penetration, greater percentage inhibition and lower IC50 against the promastigotes shows that AmB-PTM-NIO has better antileishmanial activity. The obtained findings suggested that the developed AmB-PTM-NIO-Gel has excellent capability of permeation via skin layers, sustained release profile and augmented anti-leishmanial outcome of the incorporated drugs.
Topics: Humans; Pentamidine; Amphotericin B; Leishmaniasis, Cutaneous; Combined Modality Therapy; Skin
PubMed: 36722301
DOI: 10.1080/10717544.2023.2173335 -
Parasitology Sep 2021Aquaglyceroporins (AQPs) are membrane proteins that function in osmoregulation and the uptake of low molecular weight solutes, in particular glycerol and urea. The AQP...
Aquaglyceroporins (AQPs) are membrane proteins that function in osmoregulation and the uptake of low molecular weight solutes, in particular glycerol and urea. The AQP family is highly conserved, with two major subfamilies having arisen very early in prokaryote evolution and retained by eukaryotes. A complex evolutionary history indicates multiple lineage-specific expansions, losses and not uncommonly a complete loss. Consequently, the AQP family is highly evolvable and has been associated with significant events in life on Earth. In the African trypanosomes, a role for the AQP2 paralogue, in sensitivity to two chemotherapeutic agents, pentamidine and melarsoprol, is well established, albeit with the mechanisms for cell entry and resistance unclear until very recently. Here, we discuss AQP evolution, structure and mechanisms by which AQPs impact drug sensitivity, suggesting that AQP2 stability is highly sensitive to mutation while serving as the major uptake pathway for pentamidine.
Topics: Aquaglyceroporins; Drug Resistance; Protozoan Proteins; Trypanocidal Agents; Trypanosoma
PubMed: 33602349
DOI: 10.1017/S0031182021000354 -
Biomolecules Dec 2022The S100A1 protein in humans is a calcium-binding protein. Upon Ca binding to S100A1 EF-hand motifs, the conformation of S100A1 changes and promotes interactions with...
The S100A1 protein in humans is a calcium-binding protein. Upon Ca binding to S100A1 EF-hand motifs, the conformation of S100A1 changes and promotes interactions with target proteins. RAGE consists of three domains: the cytoplasmic, transmembrane, and extracellular domains. The extracellular domain consists of C1, C2, and V domains. V domains are the primary receptors for the S100 protein. It was reported several years ago that S100A1 and RAGE V domains interact in a pathway involving S100A1-RAGE signaling, whereby S100A1 binds to the V domain, resulting in RAGE dimerization. The autophosphorylation of the cytoplasmic domain initiates a signaling cascade that regulates cell proliferation, cell growth, and tumor formation. In this study, we used pentamidine and a newly synthesized pentamidine analog (WLC-4059) to inhibit the S100A1-RAGE V interaction. H-N HSQC NMR titration was carried out to characterize the interaction between mS100A1 (mutant S100A1, C86S) and pentamidine analogs. We found that pentamidine analogs interact with S100A1 via H-N HSQC NMR spectroscopy. Based on the results, we utilized the HADDOCK program to generate structures of the mS100A1-WLC-4059 binary complex. Interestingly, the binary complex overlapped with the complex crystal structure of the mS100A1-RAGE-V domain, proving that WLC-4059 blocks interaction sites between S100A1 and RAGE-V. A WST-1 cell proliferation assay also supported these results. We conclude that pentamidine analogs could potentially enhance therapeutic approaches against cancers.
Topics: Humans; Calcium; Magnetic Resonance Spectroscopy; Neoplasms; Pentamidine; Protein Binding; Signal Transduction
PubMed: 36671465
DOI: 10.3390/biom13010081 -
Pharmaceutical Nanotechnology 2023Bioavailability is the dissimilarity between the total amount of drug exposure to a person and the actual dose received by his body. The difference in bioavailability...
BACKGROUND
Bioavailability is the dissimilarity between the total amount of drug exposure to a person and the actual dose received by his body. The difference in bioavailability between formulations of a given drug can have clinical implications.
METHODS
Poor aqueous solubility, inappropriate partition coefficient, high first-pass metabolism, narrow absorption window, and acidic pH of the stomach are the main reasons behind the low bioavailability of drugs. There are three substantial methods to vanquish these bioavailability issues, namely pharmacokinetic, biological, and pharmaceutical approaches.
RESULTS
In the pharmacokinetic approach a drug molecule is improved by making alterations in its chemical structure. In the biological approach, the course of administration of the drug is changed; for example, if a drug has very less oral bioavailability, it can be injected as parenteral or some other route if feasible. In the pharmaceutical approach to enhance bioavailability, the physiochemical properties of the drug or formulation are modified. It is cost-effective, less time-consuming, and the risk factor is also minimum. Co-solvency, particle size reduction, hydrotrophy, solid dispersion, micellar solubilisation, complexation, and colloidal drug delivery systems are some of the commonly used methods to enhance the dissolution profiles of drugs via the pharmaceutical approach. Similar to liposomes, niosomes are also vesicular carrier systems but non-ionic surfactants are used instead of phospholipids in their formulation, i.e., their bilayer is comprised of non-ionic surfactants that encircle the aqueous compartment. The niosomes are presumed to raise the bioavailability of poorly water-soluble drugs by increasing their uptake by the M cells present in Peyer's patches of lymphatic tissues of the intestine.
CONCLUSION
Niosomal technology has become an attractive method to overcome several limitations due to its various merits like biodegradability, high stability, non-immunogenic nature, low cost, and flexibility to incorporate lipophilic as well as hydrophilic drugs. The bioavailability of many BCS class II and IV drugs has been successfully enhanced using niosomal technology, like Griseofulvin, Paclitaxel, Candesartan Cilexetil, Carvedilol, Clarithromycin, Telmisartan, and Glimepiride. Niosomal technology has also been exploited for brain targeting via nasal delivery for many drugs like Nefopam, Pentamidine, Ondansetron HCl, and Bromocriptine mesylate. Based on this data, it can be concluded that niosomal technology has increased importance in bioavailability enhancement and improving the overall performance of molecules in vitro and in vivo. Thus, niosomal technology holds tremendous potential for scale-up applications, overcoming the drawbacks of conventional dosage forms.
Topics: Humans; Liposomes; Biological Availability; Drug Delivery Systems; Water; Technology; Surface-Active Agents
PubMed: 36892113
DOI: 10.2174/2211738511666230309104323 -
Preclinical Development of Pentamidine Analogs Identifies a Potent and Nontoxic Antibiotic Adjuvant.ACS Infectious Diseases Apr 2022The difficulty in treating Gram-negative bacteria can largely be attributed to their highly impermeable outer membrane (OM), which serves as a barrier to many otherwise...
The difficulty in treating Gram-negative bacteria can largely be attributed to their highly impermeable outer membrane (OM), which serves as a barrier to many otherwise active antibiotics. This can be overcome with the use of perturbant molecules, which disrupt OM integrity and sensitize Gram-negative bacteria to many clinically available Gram-positive-active antibiotics. Although many new perturbants have been identified in recent years, most of these molecules are impeded by toxicity due to the similarities between pathogen and host cell membranes. For example, our group recently reported the cryptic OM-perturbing activity of the antiprotozoal drug pentamidine. Its development as an antibiotic adjuvant is limited, however, by toxicity concerns. Herein, we took a medicinal chemistry approach to develop novel analogs of pentamidine, aiming to improve its OM activity while reducing its off-target toxicity. We identified the compound P35, which induces OM disruption and potentiates Gram-positive-active antibiotics in and . Relative to pentamidine, P35 has reduced mammalian cell cytotoxicity and hERG trafficking inhibition. Additionally, P35 outperforms pentamidine in a murine model of bacteremia. Together, this preclinical analysis supports P35 as a promising lead for further development as an OM perturbant.
Topics: Acinetobacter baumannii; Animals; Anti-Bacterial Agents; Gram-Negative Bacteria; Klebsiella pneumoniae; Mammals; Mice; Pentamidine
PubMed: 35319198
DOI: 10.1021/acsinfecdis.1c00482 -
Tropical Biomedicine Dec 2022The present study compares the in vitro effects of nanoparticles loaded pentamidine drug and conventional pentamidine on Leishmania tropica. Herein, pentamidine-loaded...
The present study compares the in vitro effects of nanoparticles loaded pentamidine drug and conventional pentamidine on Leishmania tropica. Herein, pentamidine-loaded chitosan nanoparticles (PTN-CNPs) have been synthesized through an ionic gelation method with sodium tripolyphosphate (TPP). Next, the physical characteristics of PTN-CNPs were determined through the surface texture, zeta potential, in vitro drug release, drug loading content (DLC), and encapsulation efficacy (EE) and compared its efficacy with free pentamidine (PTN) drug against promastigotes and axenic amastigotes forms of L. tropica in vitro. The PTN-CNPs displayed a spherical shape having a size of 88 nm, an almost negative surface charge (-3.09 mV), EE for PTN entrapment of 86%, and in vitro drug release of 92% after 36 h. In vitro antileishmanial activity of PTN-CNPs and free PTN was performed against Leishmania tropica KWH23 promastigote and axenic amastigote using 3-(4, 5- dimethylthiazol-2-yl)-2, 5-diphenyletetrazolium bromide (MTT) assay. It was observed that the effect of PTN-CNPs and free PTN on both forms of the parasite was dose and time dependent. Free PTN presented low efficacy even at higher dose (40 µg/ml) with 25.6 ± 1.3 and 26.5 ±1.4 mean viability rate of the promastigotes and axenic amastigotes, respectively after 72 hrs incubation. While PTN-CNPs showed strong antileishmanial effects on both forms of parasite with 16 ± 0.4 and 19 ± 0.7 mean viability rate at the same higher concentration (40 µg/ml) after 72 hrs incubation. Half maximal inhibitory concentration (IC50) values of PTN-CNPs toward promastigotes and amastigotes were obtained as 0.1375 µg/ml and 0.1910 µg/ml, respectively. In conclusion, PTN-CNPs effectively inhibited both forms of the L. tropica; however, its effect was more salient on promastigotes. This data indicates that the PTN-CNPs act as a target drug delivery system. However, further research is needed to support its efficacy in animal and human CL.
Topics: Animals; Humans; Pentamidine; Leishmania tropica; Chitosan; Antiprotozoal Agents; Drug Delivery Systems; Nanoparticles
PubMed: 36602209
DOI: 10.47665/tb.39.4.003 -
PLoS Neglected Tropical Diseases Apr 2021Human African trypanosomiasis (HAT or sleeping sickness) is caused by the parasite Trypanosoma brucei sspp. The disease has two stages, a haemolymphatic stage after the...
BACKGROUND
Human African trypanosomiasis (HAT or sleeping sickness) is caused by the parasite Trypanosoma brucei sspp. The disease has two stages, a haemolymphatic stage after the bite of an infected tsetse fly, followed by a central nervous system stage where the parasite penetrates the brain, causing death if untreated. Treatment is stage-specific, due to the blood-brain barrier, with less toxic drugs such as pentamidine used to treat stage 1. The objective of our research programme was to develop an intravenous formulation of pentamidine which increases CNS exposure by some 10-100 fold, leading to efficacy against a model of stage 2 HAT. This target candidate profile is in line with drugs for neglected diseases inititative recommendations.
METHODOLOGY
To do this, we evaluated the physicochemical and structural characteristics of formulations of pentamidine with Pluronic micelles (triblock-copolymers of polyethylene-oxide and polypropylene oxide), selected candidates for efficacy and toxicity evaluation in vitro, quantified pentamidine CNS delivery of a sub-set of formulations in vitro and in vivo, and progressed one pentamidine-Pluronic formulation for further evaluation using an in vivo single dose brain penetration study.
PRINCIPAL FINDINGS
Screening pentamidine against 40 CNS targets did not reveal any major neurotoxicity concerns, however, pentamidine had a high affinity for the imidazoline2 receptor. The reduction in insulin secretion in MIN6 β-cells by pentamidine may be secondary to pentamidine-mediated activation of β-cell imidazoline receptors and impairment of cell viability. Pluronic F68 (0.01%w/v)-pentamidine formulation had a similar inhibitory effect on insulin secretion as pentamidine alone and an additive trypanocidal effect in vitro. However, all Pluronics tested (P85, P105 and F68) did not significantly enhance brain exposure of pentamidine.
SIGNIFICANCE
These results are relevant to further developing block-copolymers as nanocarriers, improving BBB drug penetration and understanding the side effects of pentamidine.
Topics: Animals; Blood-Brain Barrier; Female; Humans; Male; Mice; Mice, Inbred BALB C; Neglected Diseases; Pentamidine; Trypanocidal Agents; Trypanosoma brucei gambiense; Trypanosoma brucei rhodesiense; Trypanosomiasis, African; Tsetse Flies
PubMed: 33857146
DOI: 10.1371/journal.pntd.0009276