scholarly journals The safety profile of Bald’s eyesalve for the treatment of bacterial infections

Author(s):  
Blessing O Anonye ◽  
Valentine Nweke ◽  
Jessica Furner-Pardoe ◽  
Rebecca Gabrilska ◽  
Afshan Rafiq ◽  
...  

AbstractThe rise in antimicrobial resistance has prompted the development of alternatives, such as plant-derived compounds, to combat bacterial infections. Bald’s eyesalve, a remedy used in the Early Medieval period, has previously been shown to have efficacy against Staphylococcus aureus grown in an in vitro model of soft tissue infection. This remedy also had bactericidal activity against methicillin-resistant S. aureus (MRSA) in a chronic mouse wound. However, the safety profile of Bald’s eyesalve has not yet been demonstrated, and this is vital before testing in humans. Here, we determined the safety potential of Bald’s eyesalve using in vitro, ex vivo, and in vivo models representative of skin or eye infections. We also confirmed that Bald’s eyesalve is active against an important eye pathogen, Neisseria gonorrhoeae. Low levels of cytotoxicity were observed in eyesalve-treated cell lines representative of skin and immune cells. Results from a bovine corneal opacity and permeability test demonstrated slight irritation to the cornea that resolved within 10 minutes. The slug mucosal irritation assay revealed that a low level of mucus was secreted by slugs exposed to eyesalve, indicating mild mucosal irritation. We obtained promising results from mouse wound closure experiments; no visible signs of irritation or inflammation were observed. Our results suggest that Bald’s eyesalve could be tested further on human volunteers to assess safety for topical application against bacterial infections.ImportanceAlternative treatment for bacterial infections are needed to combat the ever increasing repertoire of bacteria resistant to antibiotics. A medieval plant-based remedy, Bald’s eyesalve, shows promise as a substitute for the treatment of these infections. For any substance to be effective in the treatment of bacterial infections in humans, it is important to consider the safety profile. This is a key consideration in order to have the necessary regulatory approval. We demonstrate the safety profile of Bald’s eyesalve using a variety of models, including whole-organ and whole-animal models. Our results show that Bald’s eyesalve is mildly toxic to cultured human cells, but potentially suitable for patch tests on healthy human volunteers to assess safety for later clinical trials. Our work has the potential to transform the management of diseases caused by bacterial infections, such as diabetic foot ulcers, through topical application of a natural product cocktail based on Bald’s eyesalve.

2020 ◽  
Vol 10 (1) ◽  
Author(s):  
Blessing O. Anonye ◽  
Valentine Nweke ◽  
Jessica Furner-Pardoe ◽  
Rebecca Gabrilska ◽  
Afshan Rafiq ◽  
...  

Abstract The rise in antimicrobial resistance has prompted the development of alternatives to combat bacterial infections. Bald’s eyesalve, a remedy used in the Early Medieval period, has previously been shown to have efficacy against Staphylococcus aureus in in vitro and in vivo models of chronic wounds. However, the safety profile of Bald’s eyesalve has not yet been demonstrated, and this is vital before testing in humans. Here, we determined the safety potential of Bald’s eyesalve using in vitro, ex vivo, and in vivo models representative of skin or eye infections. We also confirmed that Bald’s eyesalve is active against an important eye pathogen, Neisseria gonorrhoeae. Low levels of cytotoxicity were observed in eyesalve-treated cell lines representative of skin and immune cells. Results from a bovine corneal opacity and permeability test demonstrated slight irritation to the cornea that resolved within 10 min. The slug mucosal irritation assay revealed that a low level of mucus was secreted by slugs indicating moderate mucosal irritation. We obtained promising results from mouse wound closure experiments; no visible signs of irritation or inflammation were observed. Our results suggest that Bald’s eyesalve could be tested further on human volunteers to assess safety for topical application against bacterial infections.


1998 ◽  
Vol 42 (12) ◽  
pp. 3218-3224 ◽  
Author(s):  
Hing L. Sham ◽  
Dale J. Kempf ◽  
Akhteruzammen Molla ◽  
Kennan C. Marsh ◽  
Gondi N. Kumar ◽  
...  

ABSTRACT The valine at position 82 (Val 82) in the active site of the human immunodeficiency virus (HIV) protease mutates in response to therapy with the protease inhibitor ritonavir. By using the X-ray crystal structure of the complex of HIV protease and ritonavir, the potent protease inhibitor ABT-378, which has a diminished interaction with Val 82, was designed. ABT-378 potently inhibited wild-type and mutant HIV protease (Ki = 1.3 to 3.6 pM), blocked the replication of laboratory and clinical strains of HIV type 1 (50% effective concentration [EC50], 0.006 to 0.017 μM), and maintained high potency against mutant HIV selected by ritonavir in vivo (EC50, ≤0.06 μM). The metabolism of ABT-378 was strongly inhibited by ritonavir in vitro. Consequently, following concomitant oral administration of ABT-378 and ritonavir, the concentrations of ABT-378 in rat, dog, and monkey plasma exceeded the in vitro antiviral EC50 in the presence of human serum by >50-fold after 8 h. In healthy human volunteers, coadministration of a single 400-mg dose of ABT-378 with 50 mg of ritonavir enhanced the area under the concentration curve of ABT-378 in plasma by 77-fold over that observed after dosing with ABT-378 alone, and mean concentrations of ABT-378 exceeded the EC50 for >24 h. These results demonstrate the potential utility of ABT-378 as a therapeutic intervention against AIDS.


2004 ◽  
Vol 72 (3) ◽  
pp. 227-237
Author(s):  
Nahla S. Barakat ◽  
Nawal M. Khalafallah ◽  
Said A. Khalil

The purpose of this study was to evaluate the bioavailability of locally produced 2.5 mg terbutaline sulphate tablets (brand A ) relative to a reference product, Bricanyl 2.5 mg tablets (brand 6). The study was a single dose 5 mg randomized crossover one in 15 healthy volunteers in the fasting state. Urine was collected at intervals of 24 h. Total terbutaline excreted in urine as unchanged drug and as conjugates (sulphate and glucuronide) was determined by a developed and validated HPLC method. In-vitro characteristics of both brands were similar. Based on percent of the dose excreted in urine, the oral bioavailability ranged from 33.5% to 75.8% for both brands. Statistics were applied to judge bioequivalence according to USP 24 in-vivo bioequivalence guidance. Results indicated that brand A and B were bioequivalent and hence interchangeable in medical practice.


Blood ◽  
2000 ◽  
Vol 96 (3) ◽  
pp. 878-884 ◽  
Author(s):  
Eugene Maraskovsky ◽  
Elizabeth Daro ◽  
Eileen Roux ◽  
Mark Teepe ◽  
Charlie R. Maliszewski ◽  
...  

Abstract Dendritic cells (DCs) represent a family of ontogenically distinct leukocytes involved in immune response regulation. The ability of DCs to stimulate T-cell immunity has led to their use as vectors for immunotherapy vaccines. However, it is unclear whether and to what degree in vitro–generated DCs are representative of DCs that develop in vivo. Treatment of mice with human Flt3 ligand (FL) dramatically increases the number of DCs. We report here that administration of FL to healthy human volunteers increased the number of circulating CD11c+ IL-3Rlow DC (mean 44-fold) and CD11c− IL-3Rhigh DC precursors (mean 12-fold). Moreover, the CD11c+ DCs were efficient stimulators of T cells in vitro. Thus, FL can expand the number of circulating, functionally competent human DCs in vivo.


2021 ◽  
Author(s):  
Sowmya Pattabhi ◽  
Samantha N Lotti ◽  
Mason P Berger ◽  
David J Rawlings

Sickle cell disease (SCD) is caused by a single nucleotide transversion in exon 1 of the HBB gene that changes the hydrophobicity of adult globin (βA), leading to substantial morbidity and reduced lifespan. Ex vivo autologous gene editing utilizing co-delivery of a designer nuclease along with a DNA donor template allows for precise homology-directed repair (HDR). These gene corrected cells when engrafted into the bone marrow (BM) can prove to be therapeutic and serves as an alternative to HLA-matched BM transplantation. In the current study, we extensively explored the role of single stranded oligonucleotide (ssODN) and recombinant adeno-associated 6 (rAAV6) donor template delivery to introduce a codon-optimized change (E6optE) or a sickle mutation (E6V) change following Crispr/Cas9-mediated cleavage of HBB in healthy human mobilized peripheral blood stem cells (mPBSCs). We achieved efficient HDR in vitro in edited cells and observed robust human CD45+ engraftment in the BM of NBSGW mice at 16-17 weeks. Notably, recipients of ssODN-modified HSC exhibited a significantly higher proportion of HDR-modified cells within individual BM, CD34+ and CD235+ compartments of both E6optE and E6V cohorts. We further assessed key functional outcomes including RNA transcripts analysis and globin sub-type expression. Our combined findings demonstrate the capacity to achieve clinically relevant HDR in vitro and in vivo using both donor template delivery method. The use of ssODN donor template-delivery is consistently associated with higher levels of gene correction in vivo as demonstrated by sustained engraftment of HDR-modified HSC and erythroid progeny. Finally, the HDR-based globin protein expression was significantly higher in the E6V ssODN-modified animals compared to the rAAV6-modified animals confirming that the ssODN donor template delivery outperforms rAAV6-donor template delivery.


Blood ◽  
2017 ◽  
Vol 130 (Suppl_1) ◽  
pp. 95-95
Author(s):  
Corey M Hoffman ◽  
Sarah E Latchney ◽  
Mark LaMere ◽  
Jason R Myers ◽  
John M Ashton ◽  
...  

Abstract While hematopoietic stem cells (HSCs)-intrinsic effects of aging have been explored, less is known about how HSC support is altered by the aged bone marrow microenvironment (BMME). To assess the role of the BMME in HSC aging, we compared the BMME in young (6-12 weeks) and aged (20-24 months) male mice and young (<50 years old; YO) and aged (>50 YO) human volunteers. Aged mice had remodeling of the BMME, with expansion of the marrow cavity and vascular volume compared to young mice. BMME constituents were redistributed within two distinct anatomic regions, namely endosteal bone-associated (BA) and marrow-associated (MA) cells. BA cells in aged mice contained fewer phenotypic mesenchymal/osteoblastic progenitors, with reduction in their ability to constitute colony forming units (CFUs). CFU loss was also observed in aged human volunteers. Aged murine MA had significant expansion of dysfunctional mesenchymal stem cells (MSCs) and activated macrophages (MΦ). Increased MΦ were also detected in aged human marrows. Following this in vivo characterization, we developed an ex vivo co-culture system to determine if aged murine BMME cells could impart aging characteristics to young HSCs. Young murine HSCs co-cultured with aged MA cells acquired phenotypic properties of aged HSCs, including increased CD41+ expression. Single cell RNA sequencing of Long Term-HSCs (LT-HSCs) from young and aged mice also identified upregulation of integrin-β3 (CD61) as a novel marker of aged LT-HSCs. Subsequent flow cytometry analysis confirmed the increase in CD61+ expression in vivo in aged HSCs. Importantly, aged MA - but not BA cells - also increased CD61+ expression in young HSCs ex vivo, highlighting the region-specific remodeling of the BMME that occurs with age. We then used a reductionist approach to identify targetable cellular and molecular regulators of the region-specific BMME-induced HSC aging. CD45+ and Ter119+ depletion in aged MA cells did not induce CD41+ expression in young HSCs, suggesting that a critical BMME component responsible for non-cell-autonomous HSC aging is present within the hematopoietic pool. Since marrow MΦ can regulate HSCs, we co-cultured aged MA MΦ with young MA and found that aged MΦ were sufficient to increase CD41+ expression in young HSCs. The addition of aged MΦ also expanded young MSCs, demonstrating that MΦ orchestrate both BMME remodeling and HSC aging. We next aimed to explore mechanisms by which aged MA MΦ impart aging characteristics to HSCs. Transcriptional analysis of murine MA MΦ demonstrated an increase in inflammatory activation in aged mice compared to young mice. This finding was also present in aged human MΦs. Among the inflammatory signals, interleukin-1β (IL-1β) was identified to be necessary and sufficient to mediate the aging effect of aged MA MΦ on young HSCs. Transcriptional analysis also revealed downregulation of phagocytic programs in aged MA MΦ compared to young MA MΦ. Supporting the transcriptional data, aged MA MΦs cultured in vitro demonstrated impaired ability to engulf senescent neutrophils compared to young MA MΦ. Bone marrow MΦ continuously remove large quantities of senescent neutrophils through phagocytosis, a process also known as efferocytosis. Complementing the in vitro findings, in vivo testing demonstrated that young MA MΦ are primarily responsible for engulfing senescent neutrophils and that aged MA MΦ had reduced engulfment of senescent neutrophils. No phagocytic defect was identified in aged BA MΦ, highlighting the regionalization of MΦ function within the BMME that is differentially impacted with age. Consistent with the systemic impact of the efferocytic defect of aged MA MΦ, aged mice had increased levels of circulating senescent neutrophils and. Moreover, neutrophils from aged mice had increased caspase-1 activity, a signal required for IL-1β activation. Together, these data provide evidence that aging differentially remodels two anatomically distinct BMMEs. Regional specialization of marrow MΦ was differentially impacted by aging and induced aging characteristics in HSCs. We propose that impaired removal of senescent neutrophils by aged MA MΦ increases IL-1β production, leading to local inflammation and disrupted BMME and HSC function in aged mice. Strategies aimed at restoring healthy efferocytic activity as well as diminishing IL-1β production or function could therefore reduce the aging effect on HSCs by rejuvenating the BMME. Disclosures Liesveld: Onconova: Honoraria; Seattle Genetics: Honoraria.


Blood ◽  
2019 ◽  
Vol 134 (Supplement_1) ◽  
pp. 717-717 ◽  
Author(s):  
Camille Roussel ◽  
Alexandre Morel ◽  
Michaël Dussiot ◽  
Mickael MARIN ◽  
Martin Colard ◽  
...  

Background Hypothermic storage of red blood cell (RBC) concentrates for up to 42 days is associated with biochemical, molecular, morphological, and mechanical modifications. This "storage lesion" increases with storage duration and is associated with increased clearance of transfused storage-damaged RBCs from the recipient's circulation in the first few hours post-transfusion. This rapid clearance reduces transfusion efficacy, but how it occurs is not fully elucidated. RBCs with reduced surface area called "storage-induced micro-erythrocytes" (SMEs) were recently described. Their proportion increases from 2% to 23% during storage. Their reduced surface-to-volume ratio is expected to induce rapid mechanical clearance by the spleen. We aimed to evaluate whether SMEs can be used as a marker of transfusion efficacy, if this subpopulation of RBCs is preferentially cleared by the spleen after transfusion, and if so, by which mechanisms. Methods We evaluated the proportion of SMEs in stored RBC concentrates in vitro using ImageStream and correlated it to the 51Chromium-labeled 24h post-transfusion recovery (24hPTR) in vivo in 31 healthy human volunteers. We then investigated the fate of SMEs during 8 ex vivo perfusions of human spleens (16 RBC concentrates stored for 35-42 days). Finally, we developed a mouse transfusion model to assess the fate of SMEs in vivo and determine their main mechanisms of clearance. Results The proportion of SMEs in RBC concentrates at day 42 of storage correlated negatively with 24hPTR in healthy volunteers (r=-0.42, P<0.01). When perfused ex vivo into human spleens, 15% of stored RBCs (35-42 days of storage) were cleared during the first 40 min of perfusion in a 2-step process: 7% of circulating RBCs disappeared in the first 2 min (1-2 passages through the spleen) while 8% were cleared between 10 and 40 min after initiating perfusion (>5 passages through the spleen). The percentage of SMEs correlated with splenic retention rate ex vivo (r=0.46, p<0.05). Morphological analysis of 6 stored RBC concentrates showed a mean decrease in the proportion of SMEs from 20.2% to 7.8% between the beginning and end of splenic perfusions. In our mouse transfusion model, SMEs accumulated during RBC storage. The 24hPTR also decreased with storage duration (64% on Day 14 vs. 95% on Day 1). The decrease in 24hPTR of long-stored RBCs was mostly due to clearance of the SME subpopulation. SME and morphologically normal long-stored RBC subpopulations displayed clearances of 83% and 13%, respectively. Stored RBCs accumulated predominantly in the spleen post-transfusion, and were mainly ingested by macrophages. In macrophage-depleted mice, 24hPTR improved (from 64% to 79%), splenic accumulation and clearance of SMEs were delayed, and the proportion of inflammatory monocytes increased and mediated clearance. In splenectomized mice, clearance of SMEs was not delayed, but increased accumulation was observed in the liver and bone marrow, and increased erythrophagocytosis by inflammatory monocytes was also observed. Conclusions We show that the proportion of SMEs correlates with 24hPTR in healthy human volunteers and with retention in human spleens perfused ex vivo. In vivo mouse data confirms these findings, showing that SMEs are cleared from the recipient circulation during the 24h following transfusion. Clearance of SMEs is delayed in macrophage-depleted mice, suggesting a central role of macrophages in this process. The human spleen is also likely to clear SMEs from the recipient's circulation, as suggested by experiments with human spleens perfused ex vivo. However, the spleen is not required, because SME clearance is not affected in splenectomized mice. This suggests that other organs may compensate to remove SMEs and highlights the importance of eliminating these morphologically-altered RBCs. Finally, quantification of SMEs is an operator-independent, reproducible marker of transfusion efficacy. It can be used to assess the potential of new processes to prepare and store RBC concentrates. Pre-transfusion quantification of SMEs could benefit chronically transfused patients, for whom improved transfusion efficacy is expected to reduce transfusion-induced iron overload. Disclosures Roussel: Zimmer Biomet: Research Funding. MARIN:Zimmer Biomet: Research Funding. Spitalnik:Hemanext: Membership on an entity's Board of Directors or advisory committees; Tioma, Inc.: Consultancy. Hermine:AB science: Consultancy, Equity Ownership, Honoraria, Research Funding; Celgene: Research Funding; Novartis: Research Funding. Buffet:Zimmer Biomet: Research Funding. Amireault:Zimmer Biomet: Research Funding.


2021 ◽  
Vol 23 (3) ◽  
Author(s):  
M. Hoppel ◽  
M. A. M. Tabosa ◽  
A. L. Bunge ◽  
M. B. Delgado-Charro ◽  
R. H. Guy

AbstractIt has proven challenging to quantify ‘drug input’ from a formulation to the viable skin because the epidermal and dermal targets of topically applied drugs are difficult, if not impossible, to access in vivo. Defining the drug input function to the viable skin with a straightforward and practical experimental approach would enable a key component of dermal pharmacokinetics to be characterised. It has been hypothesised that measuring drug uptake into and clearance from the stratum corneum (SC) by tape-stripping allows estimation of a topical drug’s input function into the viable tissue. This study aimed to test this idea by determining the input of nicotine and lidocaine into the viable skin, following the application of commercialised transdermal patches to healthy human volunteers. The known input rates of these delivery systems were used to validate and assess the results from the tape-stripping protocol. The drug input rates from in vivo tape-stripping agreed well with the claimed delivery rates of the patches. The experimental approach was then used to determine the input of lidocaine from a marketed cream, a typical topical product for which the amount of drug absorbed has not been well-characterised. A significantly higher delivery of lidocaine from the cream than from the patch was found. The different input rates between drugs and formulations in vivo were confirmed qualitatively and quantitatively in vitro in conventional diffusion cells using dermatomed abdominal pig skin.


2017 ◽  
Vol 8 (2) ◽  
pp. 217-230 ◽  
Author(s):  
M.F. Galvão ◽  
R.W. Bastos ◽  
L.B. Acurcio ◽  
B.B. Nascimento ◽  
S.H.C. Sandes ◽  
...  

The indigenous microbiota is the population of microorganisms normally present on the surface and mucosa of an individual, where it performs essential health functions, including the colonisation resistance (CR) against pathogens. To identify the bacteria responsible and the mechanisms involved in the CR, the germ-free (GF) animal model has been used, because in vitro studies cannot always be extrapolated to what occurs in vivo. In this study, ex vivo antagonism assays against seven enteropathogenic bacteria using stools from 15 healthy human donors confirmed that the CR showed individual variation. Using in vitro antagonism assays, 14 strains isolated from dominant faecal microbiota of donors with elevated CR were selected for mono-association in GF mice to test the in vivo antagonism against Salmonella enterica ser. Typhimurium. Mice mono-associated with Enterococcus hirae strain 8.2, Bacteroides thetaiotaomicron strain 16.2 and Lactobacillus ruminis strain 18.1 had significant reductions in faecal counts of the pathogen during the challenge. After five days of infection, the group associated with E. hirae 8.2 showed a reduction in the translocation of S. Typhimurium to the spleen, while the group associated with L. ruminis 18.1 presented an increased translocation to the liver. The histological data confirmed these results and revealed that the mice associated with E. hirae 8.2 showed fewer lesions on ileum and liver, compared to the damage caused by S. Typhimurium alone, while in mice associated with L. ruminis 18.1 there was significantly worse lesions. Concluding, from the dominant faecal microbiota from healthy human with high CR, through ex vivo, in vitro and in vivo assays, a bacterium was characterised for its high CR potential, being a candidate for probiotic use.


Pharmaceutics ◽  
2021 ◽  
Vol 13 (11) ◽  
pp. 1869
Author(s):  
Ahmed Hassen Elshafeey ◽  
Rania Moataz El-Dahmy

Paroxetine (PX) is the most potent serotonin reuptake inhibitor utilized in depression and anxiety treatment. It has drawbacks, such as having a very bitter taste, low water solubility, and undergoing extensive first pass metabolism, leading to poor oral bioavailability (<50%). This work aimed to develop and optimize palatable oral fast-dissolving films (OFDFs) loaded with a paroxetine nanosuspension. A PX nanosuspension was prepared to increase the PX solubility and permeability via the buccal mucosa. The OFDFs could increase PX bioavailability due to their rapid dissolution in saliva, without needing water, and the rapid absorption of the loaded drug through the buccal mucosa, thus decreasing the PX metabolism in the liver. OFDFs also offer better convenience to patients with mental illness, as well as pediatric, elderly, and developmentally disabled patients. The PX nanosuspension was characterized by particle size, poly dispersity index, and zeta potential. Twelve OFDFs were formulated using a solvent casting technique. A 22 × 31 full factorial design was applied to choose the optimized OFDF, utilizing Design-Expert® software (Stat-Ease Inc., Minneapolis, MN, USA). The optimized OFDF (F1) had a 3.89 ± 0.19 Mpa tensile strength, 53.08 ± 1.28% elongation%, 8.12 ± 0.13 MPa Young’s modulus, 17.09 ± 1.30 s disintegration time, and 96.02 ± 3.46% PX dissolved after 10 min. This optimized OFDF was subjected to in vitro dissolution, ex vivo permeation, stability, and palatability studies. The permeation study, using chicken buccal pouch, revealed increased drug permeation from the optimized OFDF; with a more than three-fold increase in permeation over the pure drug. The relative bioavailability of the optimized OFDF in comparison with the market tablet was estimated clinically in healthy human volunteers and was found to be 178.43%. These findings confirmed the success of the OFDFs loaded with PX nanosuspension for increasing PX bioavailability.


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