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Dental Materials : Official Publication... Jun 2023To evaluate the effect of doxycycline and dexamethasone doped nanoparticles covering titanium surfaces, on osteoblasts proliferation and differentiation.
OBJECTIVES
To evaluate the effect of doxycycline and dexamethasone doped nanoparticles covering titanium surfaces, on osteoblasts proliferation and differentiation.
METHODS
Doxycycline and dexamethasone doped polymeric nanoparticles were applied on titanium discs (Ti-DoxNPs and Ti-DexNPs). Undoped NPs and uncovered Ti discs were used as control. Human MG-63 osteoblast-like cells were cultured. Osteoblasts proliferation was tested by MTT assay. Alkaline phosphatase activity was analyzed. Differentiation gene expression was assessed by real-time quantitative polymerase chain reaction. Scanning Electron Microscopy was performed to assess osteoblasts morphology. Mean comparisons were conducted by ANOVA and Wilcoxon or Tukey tests (p < 0.05).
RESULTS
No differences in osteoblasts proliferation were found. Osteoblasts grown on Ti-DoxNPs significantly increased alkaline phosphatase activity. Doxycycline and dexamethasone nanoparticles produced an over-expression of the main osteogenic proliferative genes (TGF-β1, TGF-βR1 and TGF-βR2). The expression of Runx-2 was up-regulated. The osteogenic proteins (AP, OSX and OPG) were also overexpressed on osteoblasts cultured on Ti-DoxNPs and Ti-DexNPs. The OPG/RANKL ratio was the highest when DoxNPs were present (75-fold increase with respect to the control group). DexNPs also produced a significantly higher OPG/RANKL ratio with respect to the control (20 times higher). Osteoblasts grown on titanium discs were mainly flat and polygonal in shape, with inter-cellular connections. In contrast, osteoblasts cultured on Ti-DoxNPs or Ti-DexNPs were found to be spindle-shaped and had abundant secretions on their surfaces.
SIGNIFICANCE
DoxNPs and DexNPs were able to stimulate osteoblasts differentiation when applied on titanium surfaces, being considered potential inducers of osteogenic environment when performing regenerative procedures around titanium dental implants.
Topics: Humans; Titanium; Doxycycline; Alkaline Phosphatase; Cell Differentiation; Osteogenesis; Nanoparticles; Dexamethasone; Osteoblasts; Surface Properties; Cell Proliferation
PubMed: 37173196
DOI: 10.1016/j.dental.2023.05.004 -
BMJ Case Reports Oct 2021An 80-year-old man with no personal or family history of bleeding, presented to hospital with extensive haematomas and skin bruising after using doxycycline. His basic...
An 80-year-old man with no personal or family history of bleeding, presented to hospital with extensive haematomas and skin bruising after using doxycycline. His basic lab workup was concerning for a coagulopathy with an elevated activated partial thromboplastin time and significant anaemia. Mixing studies and other factor levels were tested that led to the diagnosis of acquired haemophilia A with low factor VIII levels and high factor VIII antibodies. He was started on steroids, but his haemoglobin level continued to drop. Later, during his treatment, he was given multiple therapeutic agents, including cyclophosphamide, rituximab and recombinant factor VII (NovoSeven-R). Gradually factor VIII levels increased and haemoglobin stabilised. The hospital course was complicated by COVID-19 pneumonia leading to acute respiratory distress syndrome; the patient eventually expired due to respiratory failure.
Topics: Aged, 80 and over; COVID-19; Doxycycline; Hemophilia A; Humans; Male; Partial Thromboplastin Time; SARS-CoV-2
PubMed: 34598965
DOI: 10.1136/bcr-2021-244748 -
Schizophrenia Bulletin Jul 2023Doxycycline and minocycline are brain-penetrant tetracycline antibiotics, which recently gained interest because of their immunomodulatory and neuroprotective...
BACKGROUND
Doxycycline and minocycline are brain-penetrant tetracycline antibiotics, which recently gained interest because of their immunomodulatory and neuroprotective properties. Observational studies have suggested that exposure to these drugs may decrease the risk to develop schizophrenia, but results are inconsistent. The aim of this study was to investigate the potential association between doxycycline use and later onset of schizophrenia.
DESIGN
We used data from 1 647 298 individuals born between 1980 and 2006 available through Danish population registers. 79 078 of those individuals were exposed to doxycycline, defined as redemption of at least 1 prescription. Survival analysis models stratified for sex with time-varying covariates were constructed to assess incidence rate ratios (IRRs) for schizophrenia (ICD-10 code F20.xx), with adjustment for age, calendar year, parental psychiatric status, and educational level.
RESULTS
In the non-stratified analysis, there was no association between doxycycline exposure and schizophrenia risk. However, men who redeemed doxycycline had a significantly lower incidence rate for schizophrenia onset compared to men that did not (IRR 0.70; 95% CI 0.57-0.86). By contrast, women had a significantly higher incidence rate for schizophrenia onset, compared to women that did not redeem doxycycline prescriptions (IRR 1.23; 95% CI 1.08, 1.40). The effects were not found for other tetracycline antibiotics (IRR 1.00; 95% CI 0.91, 1.09).
CONCLUSIONS
Doxycycline exposure is associated with a sex-dependent effect on schizophrenia risk. The next steps are replication of the results in independent well-characterized population cohorts, as well as preclinical studies to investigate sex-specific effects of doxycycline on biological mechanisms implicated in schizophrenia.
Topics: Male; Humans; Female; Schizophrenia; Doxycycline; Risk Factors; Minocycline; Anti-Bacterial Agents; Registries; Denmark
PubMed: 36869773
DOI: 10.1093/schbul/sbad008 -
Scientific Reports Mar 2022The main objective of this study was to determine the cellular and molecular effects of doxycycline on the blood-brain barrier (BBB) and protection against secondary...
The main objective of this study was to determine the cellular and molecular effects of doxycycline on the blood-brain barrier (BBB) and protection against secondary injuries following traumatic brain injury (TBI). Microvascular hyperpermeability and cerebral edema resulting from BBB dysfunction after TBI leads to elevation of intracranial pressure, secondary brain ischemia, herniation, and brain death. There are currently no effective therapies to modulate the underlying pathophysiology responsible for TBI-induced BBB dysfunction and hyperpermeability. The loss of BBB integrity by the proteolytic enzyme matrix metalloproteinase-9 (MMP-9) is critical to TBI-induced BBB hyperpermeability, and doxycycline possesses anti-MMP-9 effect. In this study, the effect of doxycycline on BBB hyperpermeability was studied utilizing molecular modeling (using Glide) in silico, cell culture-based models in vitro, and a mouse model of TBI in vivo. Brain microvascular endothelial cell assays of tight junction protein immunofluorescence and barrier permeability were performed. Adult C57BL/6 mice were subjected to sham versus TBI with or without doxycycline treatment and immediate intravital microscopic analysis for evaluating BBB integrity. Postmortem mouse brain tissue was collected to measure MMP-9 enzyme activity. It was found that doxycycline binding to the MMP-9 active sites have binding affinity of -7.07 kcal/mol. Doxycycline treated cell monolayers were protected from microvascular hyperpermeability and retained tight junction integrity (p < 0.05). Doxycycline treatment decreased BBB hyperpermeability following TBI in mice by 25% (p < 0.05). MMP-9 enzyme activity in brain tissue decreased with doxycycline treatment following TBI (p < 0.05). Doxycycline preserves BBB tight junction integrity following TBI via inhibiting MMP-9 activity. When established in human subjects, doxycycline, may provide readily accessible medical treatment after TBI to attenuate secondary injury.
Topics: Animals; Blood-Brain Barrier; Brain; Brain Injuries, Traumatic; Doxycycline; Humans; Mice; Mice, Inbred C57BL
PubMed: 35354869
DOI: 10.1038/s41598-022-09394-4 -
American Journal of Respiratory and... Sep 2023
Topics: Humans; Anti-Bacterial Agents; Doxycycline; Double-Blind Method; Pulmonary Disease, Chronic Obstructive; Disease Progression
PubMed: 37531185
DOI: 10.1164/rccm.202307-1302ED -
Deutsches Arzteblatt International Mar 2020
Topics: Antimalarials; Dermatitis, Phototoxic; Doxycycline; Female; Humans; Young Adult
PubMed: 32343652
DOI: 10.3238/arztebl.2020.0196 -
Travel Medicine and Infectious Disease 2022Antibiotics predispose travellers to acquire multidrug-resistant bacteria, such as extended-spectrum beta-lactamase-producing Enterobacterales (ESBL-PE). Although widely... (Review)
Review
BACKGROUND
Antibiotics predispose travellers to acquire multidrug-resistant bacteria, such as extended-spectrum beta-lactamase-producing Enterobacterales (ESBL-PE). Although widely used in antimalarial prophylaxis, doxycycline has scarcely been studied in this respect.
METHODS
We explored the impact of doxycycline on rates of traveller's diarrhoea (TD), ESBL-PE acquisition and, particularly, doxycycline co-resistance among travel-acquired ESBL-PE in a sample of 412 visitors to low- and middle-income countries. We reviewed the literature on traveller studies of doxycycline/tetracycline resistance among stool pathogens and the impact of doxycycline on TD rates, ESBL-PE acquisition, and doxycycline/tetracycline resistance.
RESULTS
The TD rates were similar for doxycycline users (32/46; 69.6%) and non-users (256/366; 69.9%). Of the 90 travel-acquired ESBL-PE isolates, 84.4% were co-resistant to doxycycline: 100% (11/11) among users and 82.3% (65/79) among non-users. The literature on doxycycline's effect on TD was not conclusive nor did it support a recent decline in doxycycline resistance. Although doxycycline did not increase ESBL-PE acquisition, doxycycline-resistance among stool pathogens proved more frequent for users than non-users.
CONCLUSIONS
Our prospective data and the literature review together suggest the following: 1) doxycycline does not prevent TD; 2) doxycycline use favours acquisition of doxy/tetracycline-co-resistant intestinal bacteria; 3) although doxycycline does not predispose to travel-related ESBL-PE acquisition per se, it selects ESBL-PE strains co-resistant to doxycycline; 4) doxycycline resistance rates are high among stool bacteria in general with no evidence of any tendency to decrease.
Topics: Anti-Bacterial Agents; Antimalarials; Bacteria; Diarrhea; Doxycycline; Enterobacteriaceae; Enterobacteriaceae Infections; Humans; Prospective Studies; Travel; Travel-Related Illness; beta-Lactamases
PubMed: 35872253
DOI: 10.1016/j.tmaid.2022.102403 -
Molecules (Basel, Switzerland) Aug 2021In this study, broilers were fed with heavy-metal-containing diets (Zn, Cu, Pb, Cr, As, Hg) at three rates (T1: 5 kg premix/ton feed, T2: 10 kg premix/ton feed and T3:...
In this study, broilers were fed with heavy-metal-containing diets (Zn, Cu, Pb, Cr, As, Hg) at three rates (T1: 5 kg premix/ton feed, T2: 10 kg premix/ton feed and T3: 15 kg premix/ton feed) and Doxycycline (DOX) and Gatifloxacin (GAT) at low or high doses (T4: 31.2 mg DOX/bird/day and 78 mg GAT/bird/day, T5: 15.6 mg DOX/bird/day and 48 mg GAT/bird/day) to assess the accumulation of various heavy metals and the fate of two antibiotics in broiler manure after 35 days of aerobic composting. The results indicated that the two antibiotics changed quite differently during aerobic composting. About 14.96-15.84% of Doxycycline still remained at the end of composting, while Gatifloxacin was almost completely removed within 10 days of composting. The half-lives of Doxycycline were 13.75 and 15.86 days, while the half-lives of Gatifloxacin were only 1.32 and 1.38 days. Based on the Redundancy analysis (RDA), the concentration of antibiotics was significantly influenced by physico-chemical properties (mainly temperature and pH) throughout the composting process. Throughout the composting process, all heavy metal elements remained concentrated in organic fertilizer. In this study the Cr content reached 160.16 mg/kg, 223.98 mg/kg and 248.02 mg/kg with increasing premix feed rates, similar to Zn, which reached 258.2 mg/kg, 312.21 mg/kg and 333.68 mg/kg. Zn and Cr concentrations well exceeded the United States and the European soil requirements. This experiment showed that antibiotic residues and the accumulation of heavy metals may lead to soil contamination and pose a risk to the soil ecosystem.
Topics: Animals; Composting; Doxycycline; Gatifloxacin; Manure; Metals, Heavy
PubMed: 34500659
DOI: 10.3390/molecules26175225 -
Clinical Infectious Diseases : An... Aug 2022Despite clinical practice guideline recommendations to use doxycycline as part of combination therapy for some patients hospitalized with pneumonia, there is minimal... (Observational Study)
Observational Study
BACKGROUND
Despite clinical practice guideline recommendations to use doxycycline as part of combination therapy for some patients hospitalized with pneumonia, there is minimal evidence supporting this recommendation. Our aim was to examine the association between beta-lactam plus doxycycline and mortality for patients hospitalized with community-acquired pneumonia.
METHODS
We identified patients >65 years of age admitted to any US Department of Veterans Affairs hospital in fiscal years 2002-2012 with a discharge diagnosis of pneumonia. We excluded those patients who did not receive antibiotic therapy concordant with the 2019 American Thoracic Society/Infectious Diseases Society of America (ATS/IDSA) clinical practice guidelines. Using propensity score matching, we examined the association of doxycycline with 30- and 90-day mortality.
RESULTS
Our overall cohort was comprised of 70533 patients and 5282 (7.49%) received doxycycline. Unadjusted 30-day mortality was 6.4% for those who received a beta-lactam plus doxycycline versus 9.1% in those who did not (P < .0001), and 90-day mortality was 13.8% for those who received a beta-lactam + doxycycline versus 16.8% for those who did not (P < .0001). In the propensity score matched models, both 30- (odds ratio 0.72, 95% confidence interval [CI], .63-.84) and 90-day (0.83, 95% CI, .74-.92) mortality were significantly lower for those who received doxycycline.
CONCLUSIONS
In this retrospective observational cohort study, we found that doxycycline use, as part of guideline-concordant antibiotic therapy, was associated with lower 30- and 90-day mortality than regimens without doxycycline. While this supports the safety and effectiveness of antibiotic regimes that include doxycycline, additional studies, especially randomized clinical trials, are needed to confirm this.
Topics: Anti-Bacterial Agents; Community-Acquired Infections; Doxycycline; Drug Therapy, Combination; Humans; Pneumonia; Retrospective Studies; beta-Lactams
PubMed: 34751745
DOI: 10.1093/cid/ciab863 -
The Journal of Antimicrobial... Oct 2022Antibiotics are used to treat bacterial infections but also impact immunity. This is usually attributed to antibiotic-induced dysbiosis of the microbiota, but...
BACKGROUND
Antibiotics are used to treat bacterial infections but also impact immunity. This is usually attributed to antibiotic-induced dysbiosis of the microbiota, but antibiotics may have a direct effect on immune cells and immunity-associated receptors, such as Toll-like receptors (TLRs).
OBJECTIVES
To investigate whether antibiotics alter TLR2/1, TLR2/6 and TLR4 activity in immune cells.
METHODS
We evaluated the effects of amoxicillin, ciprofloxacin, doxycycline and erythromycin on TLR2/1-, TLR2/6- and TLR4-induced NF-κB activation in THP1-XBlue™-MD2-CD14 cells. Furthermore, we studied TNF-α and IL-6 levels in THP-1-derived macrophages after exposure to these antibiotics and TLR ligands.
RESULTS
Amoxicillin had no effect on any of the TLRs studied. However, ciprofloxacin reduced TLR2/1, TLR2/6 and TLR4 activity in THP1-XBlue™-MD2-CD14 cells and decreased TLR2/1-induced TNF-α and IL-6 in macrophages. Doxycycline reduced TLR2/6 and TLR4 activity in THP1-XBlue™-MD2-CD14 cells and TNF-α and IL-6 levels in response to TLR2/6 stimulation in macrophages. Erythromycin decreased TLR2/1 and TLR4 activity in THP1-XBlue™-MD2-CD14 cells without changes in TNF-α and IL-6 levels in macrophages. In addition, ciprofloxacin decreased the expression of TLR2 mRNA.
CONCLUSIONS
These results suggest that some antibiotics may attenuate TLR-dependent monocyte/macrophage responses and likely reduce bacterial clearance. The latter is particularly important in infections with AMR bacteria, where misprescribed antibiotics not only fail in control of AMR infections but might also weaken host defence mechanisms by limiting innate immune responses. Our data suggest that efforts should be made to prevent the deterioration of the immune response during and after antibiotic treatment.
Topics: Monocytes; Toll-Like Receptor 2; Toll-Like Receptor 4; Doxycycline; Tumor Necrosis Factor-alpha; Interleukin-6; Erythromycin; Ciprofloxacin; Amoxicillin; Macrophages; Toll-Like Receptors; Anti-Bacterial Agents
PubMed: 35897135
DOI: 10.1093/jac/dkac254