Structural Preservation Does Not Ensure Function at Sensory Ia-Motoneuron Synapses following Peripheral Nerve Injury and Repair.

Injury that severs peripheral nerves often results in long-lasting motor behavioral deficits and in reorganization of related spinal motor circuitry, neither of which reverse even after nerve regeneration. Stretch areflexia and gait ataxia, for example, emerge from a combination of factors including degeneration of Ia-motoneuron synapses between peripherally damaged Ia muscle spindle afferents and motoneurons. Based on evidence that nerve injury acts via immune responses to induce synapse degeneration, we hypothesized that suppressing inflammatory responses would preserve Ia-motoneuron connectivity and aid in restoring normal function. We tested our hypothesis by administering the anti-inflammatory agent minocycline in male and female rats following axotomy of a peripheral nerve. The connectivity of Ia-motoneuron synapses was then assessed both structurally and functionally at different time points. We found that minocycline treatment overcame the physical loss of Ia contacts on motoneurons which are otherwise lost after axotomy. While necessary for functional recovery, synaptic preservation was not sufficient to overcome functional decline expressed as smaller than normal stretch-evoked synaptic potentials evoked monosynaptically at Ia-motoneuron connections and an absence of the stretch reflex. These findings demonstrate a limited capacity of minocycline to rescue normal sensorimotor behavior, illustrating that structural preservation of synaptic connectivity does not ensure normal synaptic function.SIGNIFICANCE STATEMENT Here we demonstrate that acute treatment with the semisynthetic tetracycline anti-inflammatory agent minocycline permanently prevents the comprehensive loss of synaptic contacts made between sensory neurons and spinal motoneurons following peripheral nerve injury and eventual regeneration. Treatment failed, however, to rescue normal function of those synapses or the reflex circuit they mediate. These findings demonstrate that preventing synaptic disconnection alone is not sufficient to restore neural circuit operation and associated sensorimotor behaviors.

A randomised double-blind placebo-controlled trial of minocycline and/or omega-3 fatty acids added to treatment as usual for at risk Mental States: The NAYAB study.

BACKGROUND: Inflammatory mechanisms are thought to contribute to the onset of psychosis in persons with an at-risk mental state (ARMS). We investigated whether the anti-inflammatory properties of minocycline and omega-3 polyunsaturated fatty acids (omega-3), alone or synergistically, would prevent transition to psychosis in ARMS in a randomised, double-blind, placebo-controlled trial in Pakistan. METHODS: 10,173 help-seeking individuals aged 16-35 years were screened using the Prodromal Questionaire-16. Individuals scoring 6 and over were interviewed using the Comprehensive Assessment of At-Risk Mental States (CAARMS) to confirm ARMS. Participants (n = 326) were randomised to minocycline, omega-3, combined minocycline and omega-3 or to double placebo for 6 months. The primary outcome was transition to psychosis at 12 months. FINDINGS: Forty-five (13.8 %) participants transitioned to psychosis. The risk of transition was greater in those randomised to omega-3 alone or in combination with minocycline (17.3.%), compared to 10.4 % in those not exposed to omega-3; a risk-ratio (RR) of 1.67, 95 % CI [0.95, 2.92] p = 0.07. The RR for transitions on minocycline vs. no minocycline was 0.86, 95 % CI [0.50, 1.49] p > 0.10. In participants who did not become psychotic, CAARMS and depression symptom scores were reduced at six and twelve months (mean CAARMS difference = 1.43; 95 % CI [0.33, 1.76] p < 0.01 in those exposed to omega-3. Minocycline did not affect CAARMS or depression scores. INTERPRETATION: In keeping with other studies, omega-3 appears to have beneficial effects on ARMS and mood symptom severity but it increased transition to psychosis, which may reflect metabolic or developmental consequences of chronic poor nutrition in the population. Transition to psychosis was too rare to reveal a preventative effect of minocycline but minocycline did not improve symptom severity. ARMS symptom severity and transition to psychosis appear to have distinct pathogeneses which are differentially modulated by omega-3 supplementation. FUNDING: The study was funded by the Stanley Research Medical Institute.

Optimization of Minocycline-Containing Bismuth Quadruple Therapy for Helicobacter pylori Rescue Treatment: A Real-World Evidence Study.

BACKGROUND: The optimal dosage of minocycline remains unclear for Helicobacter pylori (H. pylori) eradication. We aimed to evaluate the efficacy and safety of four different regimens with minocycline and metronidazole compared to classical bismuth quadruple therapy for H. pylori rescue treatment. MATERIALS AND METHODS: From March 2021 to March 2024, refractory H. pylori-infected patients with at least two previous treatment failures who received 14-day therapy with b.i.d. proton pump inhibitor 20 mg and bismuth 220 mg, plus tetracycline 400 mg q.i.d and metronidazole 400 mg q.i.d (BQT), or minocycline 50 mg q.i.d and metronidazole 400 mg q.i.d (PBMn4M4), or minocycline 50 mg t.i.d and metronidazole 400 mg t.i.d (PBMn3M3), or minocycline 50 mg b.i.d and metronidazole 400 mg q.i.d (PBMn2M4), or minocycline 50 mg b.i.d and metronidazole 400 mg t.i.d (PBMn2M3) were included in this retrospective study. H. pylori eradication was assessed by 13C-urea breath test at least 6 weeks after treatment. All adverse effects during treatment were recorded. RESULTS: Totally, 823 patients were enrolled: 251 with BQT, 97 with PBMn4M4, 191 with PBMn3M3, 108 with PBMn2M4, and 176 with PBMn2M3. The eradication rates of BQT, PBMn4M4, PBMn3M3, PBMn2M4, and PBMn2M3 were 89.2%, 87.6%, 91.6%, 88.0%, and 91.5%, respectively, by intention-to-treat analysis; 96.1%, 97.7%, 97.8%, 96.9%, and 97.6%, respectively, by modified intention-to-treat analysis; 97.1%, 97.5%, 97.7%, 96.8%, and 97.6%, respectively, by per-protocol analysis. Metronidazole resistance did not affect the efficacy of all groups. PBMn2M3 group achieved the greatest compliance and the fewest moderate and severe adverse events. CONCLUSIONS: The novel bismuth-containing quadruple therapy with a low dose of minocycline and metronidazole is an alternative to classical bismuth quadruple therapy for H. pylori rescue treatment with superior safety and compliance. TRIAL REGISTRATION: ClinicalTrials.gov identifier: NCT06332599.

Guidelines of care for the management of acne vulgaris.

BACKGROUND: Acne vulgaris commonly affects adults, adolescents, and preadolescents aged 9 years or older. OBJECTIVE: The objective of this study was to provide evidence-based recommendations for the management of acne. METHODS: A work group conducted a systematic review and applied the Grading of Recommendations, Assessment, Development, and Evaluation approach for assessing the certainty of evidence and formulating and grading recommendations. RESULTS: This guideline presents 18 evidence-based recommendations and 5 good practice statements. Strong recommendations are made for benzoyl peroxide, topical retinoids, topical antibiotics, and oral doxycycline. Oral isotretinoin is strongly recommended for acne that is severe, causing psychosocial burden or scarring, or failing standard oral or topical therapy. Conditional recommendations are made for topical clascoterone, salicylic acid, and azelaic acid, as well as for oral minocycline, sarecycline, combined oral contraceptive pills, and spironolactone. Combining topical therapies with multiple mechanisms of action, limiting systemic antibiotic use, combining systemic antibiotics with topical therapies, and adding intralesional corticosteroid injections for larger acne lesions are recommended as good practice statements. LIMITATIONS: Analysis is based on the best available evidence at the time of the systematic review. CONCLUSIONS: These guidelines provide evidence-based recommendations for the management of acne vulgaris.

Comparison of Doxycycline or Minocycline to Sulfamethoxazole-Trimethoprim for Treatment of Stenotrophomonas maltophilia Pneumonia.

BACKGROUND: Stenotrophomonas maltophilia is a multidrug-resistant organism with limited antibiotic treatment options. Minocycline and doxycycline may be appropriate, but clinical data are limited. OBJECTIVE: To compare tetracyclines (minocycline and doxycycline [TCN]) with standard of care, sulfamethoxazole-trimethoprim (TMP-SMZ), in S. maltophilia pneumonia treatment. METHODS: This retrospective, 2-center study evaluated patients treated for S. maltophilia pneumonia with TCN or TMP-SMZ for clinical success, defined as resolution of leukocytosis, fever, and tachypnea. Patients were classified as treatment with TCN or TMP-SMZ based on definitive agent used for ≥50% of the treatment course and ≥4 days. Inclusion criteria were age ≥18 years, S. maltophilia confirmed on respiratory culture from January 2013 to November 2020, and appropriate definitive antibiotic dosing. Pregnancy, incarceration, S. maltophilia-resistant or intermediate to definitive therapy, and combination therapy for treatment of S. maltophilia pneumonia were exclusion criteria. Secondary outcomes were microbiologic success and recurrence or reinfection within 30 days requiring treatment. RESULTS: A total of 80 patients were included (21 TCN [15 minocycline, 6 doxycycline], 59 TMP-SMZ). There was no difference in clinical success (28.6% vs 25.4%; P = 0.994), microbiologic success (n = 28, 55.6% vs 66.4%; P = 0.677), or recurrence or reinfection (n = 24, 66.7% vs 26.7%; P = 0.092) between TCN and TMP-SMZ, respectively. CONCLUSION AND RELEVANCE: Clinical and microbiologic success rates were similar in patients treated with TCN compared with TMP-SMZ for S. maltophilia pneumonia. These data suggest minocycline and doxycycline may be options to treat S. maltophilia pneumonia, but conclusive clinical data continue to be lacking.

Minocycline induced apoptosis and suppressed expression of matrix metalloproteinases 2 and 9 in the breast cancer MCF-7 cells.

BACKGROUND: In women, breast cancer is the second most frequent type of cancer. Looking for new and effective cancer-specific therapies with little to no adverse effects on healthy cells is critical. OBJECTIVE: Minocycline, a second-generation tetracycline, has shown anticancer effects by targeting multiple pathways in various cancers. This study aimed to determine minocycline effects on the cell proliferation, apoptosis, and invasion of the human MCF-7 cells. METHODS: MTT assay was used to evaluate the cytotoxicity of minocycline on the cells. Flow cytometry was performed to investigate the induction of apoptosis and the cell cycle progression. The expression levels of apoptotic and migration proteins and genes were assessed by western blotting and qRT-PCR. The scratch test was performed to evaluate the anti-migration effect of the drug. RESULTS: The results indicated that the IC50 value of minocycline for MCF-7 cells was 36.10 µM. Minocycline treatment caused sub-G1 cell accumulation, indicating a significant apoptotic effect on the MCF-7 cells. Annexin-V/PI staining revealed a significant rise in early and late apoptotic cell percentages. Minocycline up-regulated Bax and Caspase-3 expression and down-regulated Bcl-2 and Pro-Cas3. The scratch test revealed significant anti-migration effects for minocycline. Furthermore, it caused down-regulation of MMP-2 and MMP-9 in a concentration-dependent method. CONCLUSION: These findings further confirmed the anticancer effect of minocycline and highlighted that minocycline maybe considered as potential therapeutic agent for breast cancer treatment.

Japanese spotted fever complicated by acute sensorineural hearing loss.

Japanese spotted fever is an emerging rickettsiosis caused by Rickettsia japonica and is characterized by high fever, rash, and eschar formation. Other symptoms are often vague and nonspecific and include headaches, nausea, vomiting, and myalgia. We present a case of a 46-year-old woman with Japanese spotted fever, complicated by transient bilateral sensorineural hearing loss and presenting cutaneous IgM/IgG immune complex vasculitis. The patient was admitted with a history of several days of high fever, generalized skin erythema, and hearing impairment. Laboratory findings revealed thrombocytopenia and elevated liver enzyme and C-reactive protein levels. Pure-tone audiometry revealed bilateral sensorineural hearing loss, and a skin biopsy revealed leukocytoclastic vasculitis with deposition of C3 and IgM on the vessel walls. Under the tentative diagnosis of rickettsiosis, scrub typhus, or Japanese spotted fever, the patient was treated with minocycline, and her symptoms improved within approximately 10 days. A definitive diagnosis was made on the basis of a serological test showing increased antibody levels against Rickettsia japonica. Japanese spotted fever can cause transient sensorineural hearing loss, a rare complication that presents with cutaneous IgM/IgG immune complex vasculitis.

A systematic review of case series and clinical trials investigating systemic oral or injectable therapies for the treatment of vitiligo.

AIMS AND OBJECTIVES: The purpose of this study is to investigate the effectiveness and safety of oral and injectable systemic treatments, such as methotrexate, azathioprine, cyclosporine, tofacitinib, baricitinib, corticosteroids, statins, zinc, apremilast, etc., for treating vitiligo lesions. METHOD: Databases including PubMed, Scopus, and Web of Science were meticulously searched for studies spanning from 2010 to August 2023, focusing on systemic oral and injectable therapies for vitiligo, using comprehensive keywords and search syntaxes tailored to each database. Key data extracted included study design, treatment efficacy, patient outcomes, patient satisfaction, and safety profiles. RESULTS: In a total of 42 included studies, oral mini-pulse corticosteroid therapy (OMP) was the subject of six studies (14.2%). Minocycline was the focus of five studies (11.9%), while methotrexate, apremilast, and tofacitinib each were examined in four studies (9.5%). Antioxidants and Afamelanotide were the subjects of three studies each (7.1%). Cyclosporine, simvastatin, oral zinc, oral corticosteroids (excluding OMP) and injections, and baricitinib were each explored in two studies (4.8%). Azathioprine, mycophenolate mofetil, and Alefacept were the subjects of one study each (2.4%). CONCLUSION: Systemic treatments for vitiligo have been successful in controlling lesions without notable side effects. OMP, Methotrexate, Azathioprine, Cyclosporine, Mycophenolate mofetil, Simvastatin, Apremilast, Minocycline, Afamelanotide, Tofacitinib, Baricitinib, Antioxidants, and oral/injectable corticosteroids are effective treatment methods. However, oral zinc and alefacept did not show effectiveness.

3Mixtatin versus MTA in pulp therapy of primary teeth: a systematic review and meta-analysis of current randomized controlled trials.

AIM: 3Mixtatin (a combination of Metronidazole, Minocycline, and Ciprofloxacin along with statins) is a novel biomaterial in pulp therapy, while Mineral Trioxide Aggregate (MTA) is considered the gold standard in endodontics. This study aimed to compare the clinical and radiographic success rates of MTA and 3Mixtatin in pulp therapy of primary teeth. METHODS AND MATERIALS: MEDLINE (PubMed), CENTRAL, Web of Science, Scopus, ProQuest databases, and Google Scholar were searched to identify randomized controlled trials (RCTs) on pulp therapy with 3Mixtatin and MTA in primary teeth, published up to February 2023. It should be noted that the protocol was previously registered in the International Prospective Register of Systematic Reviews (PROSPERO; CRD42021243626). RCTs were assessed independently by two researchers in terms of eligibility and quality. Data extracted and tabulated. The Cochrane Risk of Bias (RoB-2) tool was used to assess the risk of bias. The effect sizes were evaluated utilizing risk ratios (RRs). The heterogeneity investigation was conducted utilizing I² measurement at α = 0.10. RESULTS: Out of 86 retrieval records, four articles met the inclusion criteria. Based on clinical and radiographic outcomes, the application of 3Mixtatin in the pulp therapy of primary teeth was as successful as MTA in 12 months (Clinical RR = 1.087 | Radiographic RR = 2.132). The RoB-2 tool showed a low risk of bias in all included RCTs. CONCLUSION: The limited evidence showed the clinical and radiographic efficacy of 3Mixtatin as a potential alternative to MTA. Further empirical research with larger sample sizes and strict methodology will be essential to substantiate this assertion.

The ratio of M1 to M2 microglia in the striatum determines the severity of L-Dopa-induced dyskinesias.

L-Dopa, while treating motor symptoms of Parkinson's disease, can lead to debilitating L-Dopa-induced dyskinesias, limiting its use. To investigate the causative relationship between neuro-inflammation and dyskinesias, we assessed if striatal M1 and M2 microglia numbers correlated with dyskinesia severity and whether the anti-inflammatories, minocycline and indomethacin, reverse these numbers and mitigate against dyskinesia. In 6-OHDA lesioned mice, we used stereology to assess numbers of striatal M1 and M2 microglia populations in non-lesioned (naïve) and lesioned mice that either received no L-Dopa (PD), remained non-dyskinetic even after L-Dopa (non-LID) or became dyskinetic after L-Dopa treatment (LID). We also assessed the effect of minocycline/indomethacin treatment on striatal M1 and M2 microglia and its anti-dyskinetic potential via AIMs scoring. We report that L-Dopa treatment leading to LIDs exacerbates activated microglia numbers beyond that associated with the PD state; the severity of LIDs is strongly correlated to the ratio of the striatal M1 to M2 microglial numbers; in non-dyskinetic mice, there is no M1/M2 microglia ratio increase above that seen in PD mice; and reducing M1/M2 microglia ratio using anti-inflammatories is anti-dyskinetic. Parkinson's disease is associated with increased inflammation, but this is insufficient to underpin dyskinesia. Given that L-Dopa-treated non-LID mice show the same ratio of M1/M2 microglia as PD mice that received no L-Dopa, and, given minocycline/indomethacin reduces both the ratio of M1/M2 microglia and dyskinesia severity, our data suggest the increased microglial M1/M2 ratio that occurs following L-Dopa treatment is a contributing cause of dyskinesias.

Development of Modernized Acinetobacter baumannii Susceptibility Test Interpretive Criteria for Recommended Antimicrobial Agents Using Pharmacometric Approaches.

Acinetobacter baumannii-Acinetobacter calcoaceticus complex (referred to herein as A. baumannii) treatment guidelines contain numerous older antimicrobial agents with susceptibility test interpretive criteria (STIC, also known as susceptibility breakpoints) set using only epidemiological data. We utilized a combination of in vitro surveillance data, preclinical murine thigh and lung infection models, population pharmacokinetics, simulation, and pharmacokinetic/pharmacodynamic (PK/PD) target attainment analyses to evaluate A. baumannii STIC for four commonly recommended antimicrobials from different classes (amikacin, ceftazidime, ciprofloxacin, and minocycline). Antimicrobial in vitro surveillance data were based on 1,647 clinical A. baumannii isolates obtained from 109 centers in the United States and Europe. Among these isolates, 5 were selected for evaluation in murine infection models based on fitness and MIC variability. PK and dose-ranging studies were conducted using neutropenic murine thigh and lung infection models The MIC ranges for the 5 isolates evaluated were as follows: amikacin, 2 to 32 µg/mL; ceftazidime, 4 to 16 µg/mL; ciprofloxacin, 0.12 to 2 µg/mL; minocycline, 0.25 to 4 µg/mL. All organisms grew ≥1.5 log10 CFU in both models in untreated controls. Plasma and epithelial lining fluid (ELF) pharmacokinetics for all drugs were determined in mice using liquid chromatography-tandem mass spectrometry (LC-MS/MS) methods. For each isolate, 5 dose levels of each drug were tested individually in the thigh and lung infection model. The inoculum ranged from 7.9 to 8.4 and 6.8 to 7.7 log10 CFU/mL for the lung and thigh models, respectively. PK/PD targets associated with net bacterial stasis and 1- and 2-log10 CFU reductions from baseline were identified for each organism/infection model using Hill-type models. Population pharmacokinetic models for each agent were identified from the literature. Using demographic variables for simulated patients with hospital-acquired or ventilator-associated bacterial pneumonia or urinary tract infections (including acute pyelonephritis) who were administered maximal dosing regimens of each agent, estimates of protein binding, and ELF penetration ratios based on data from the literature, free-drug plasma and total-drug concentration-time profiles were generated, and PK/PD indices by MIC were calculated. Percent probabilities of attaining median and randomly assigned PK/PD targets associated with the above-described endpoints were determined. Recommended susceptible breakpoints for each agent were those representing the highest MIC at which the percent probabilities of achieving PK/PD targets associated with a 1-log10 CFU reduction from baseline approached or were ≥90%. The following susceptible breakpoints for A. baumannii were identified: amikacin, ≤8 µg/mL for pneumonia; ceftazidime, ≤32 and ≤8 µg/mL for pneumonia; ciprofloxacin, ≤1 µg/mL; and minocycline, ≤0.5/≤1 µg/mL which correspond to the standard and high minocycline dosing regimens of 200 mg per day and 200 mg every 12 h, respectively. Implementation of appropriate STIC will help clinicians optimally use the above-described agents and improve the likelihood of successful patient outcomes.

Minocycline protects against microgliopathy in a Csf1r haplo-insufficient mouse model of adult-onset leukoencephalopathy with axonal spheroids and pigmented glia (ALSP).

BACKGROUND: Mutations in colony-stimulating factor 1 receptor (CSF1R) are known to cause adult-onset leukoencephalopathy with axonal spheroids and pigmented glia (ALSP), which has been recently demonstrated as a primary microgliopathy characterized by cognitive impairment. Although the molecular mechanism underlying CSF1R-mediated microgliopathy remains unclear, therapeutic strategies have generally targeted modulation of microglial function. In particular, the microglial inhibitor, minocycline, has been shown to attenuate learning and memory deficits in several neurodegenerative diseases. The objectives of this study were to investigate the pathogenic mechanisms underlying ALSP and to explore the therapeutic effects of minocycline in an in vivo model of ALSP. We hypothesized that inhibiting microglial activation via minocycline could reverse the behavior and pathological defects in ALSP model mice. METHODS: We generated a Csf1r haploinsufficiency mouse model of ALSP using CRISPR/Cas9 genome editing and conducted electrophysiological recordings of long-term potentiation (LTP) and behavioral tests to validate the recapitulation of clinical ALSP characteristics in 8- to 11-month-old mice. RNA-sequencing was used to explore enriched gene expression in the molecular pathogenesis of ALSP. Microglial activation was assessed by immunofluorescent detection of Iba1 and CD68 in brain sections of male ALSP mice and pro-inflammatory activation and phagocytosis were assessed in Csf1r+/- microglia. Therapeutic effects were assessed by behavioral tests, histological analysis, and morphological examination after four weeks of intraperitoneal injection with minocycline or vehicle control in Csf1r+/- mice and wild-type control littermates. RESULTS: We found that synaptic function was reduced in LTP recordings of neurons in the hippocampal CA1 region, while behavioral tests showed impaired spatial and cognitive memory specifically in male Csf1r+/- mice. Increased activation, pro-inflammatory cytokine production, and enhanced phagocytic capacity were also observed in Csf1r+/- microglia. Treatment with minocycline could suppress the activation of Csf1r+/- microglia both in vitro and in vivo. Notably, the behavioral and pathological deficits in Csf1r+/- mice were partially rescued by minocycline administration, potentially due to inhibition of microglial inflammation and phagocytosis in Csf1r+/- mice. CONCLUSIONS: Our study shows that CSF1R deficiency results in aberrant microglial activation, characterized by a pro-inflammatory phenotype and enhanced phagocytosis of myelin. Our results also indicate that microglial inhibition by minocycline can ameliorate behavioral impairment and ALSP pathogenesis in CSF1R-deficient male mice, suggesting a potential therapeutic target for CSF1R-related leukoencephalopathy. Collectively, these data support that minocycline confers protective effects against CSF1R-related microgliopathy in male ALSP model mice.

MMP9-Responsive Graphene Oxide Quantum Dot-Based Nano-in-Micro Drug Delivery System for Combinatorial Therapy of Choroidal Neovascularization.

Age-related macular degeneration (AMD), especially wet AMD with choroidal neovascularization (CNV), commonly causes blindness in older patients and disruption of the choroid followed by second-wave injuries, including chronic inflammation, oxidative stress, and excessive matrix metalloproteinase 9 (MMP9) expression. Increased macrophage infiltrate in parallel with microglial activation and MMP9 overexpression on CNV lesions is shown to contribute to the inflammatory process and then enhance pathological ocular angiogenesis. Graphene oxide quantum dots (GOQDs), as natural antioxidants, exert anti-inflammatory effects and minocycline is a specific macrophage/microglial inhibitor that can suppress both macrophage/microglial activation and MMP9 activity. Herein, an MMP9-responsive GOQD-based minocycline-loaded nano-in-micro drug delivery system (C18PGM) is developed by chemically bonding GOQDs to an octadecyl-modified peptide sequence (C18-GVFHQTVS, C18P) that can be specifically cleaved by MMP9. Using a laser-induced CNV mouse model, the prepared C18PGM shows significant MMP9 inhibitory activity and anti-inflammatory action followed by antiangiogenic effects. Moreover, C18PGM combined with antivascular endothelial growth factor antibody bevacizumab markedly increases the antiangiogenesis effect by interfering with the "inflammation-MMP9-angiogenesis" cascade. The prepared C18PGM shows a good safety profile and no obvious ophthalmic or systemic side effects. The results taken together suggest that C18PGM is an effective and novel strategy for combinatorial therapy of CNV.

Emerging infections in vulnerable hosts: Stenotrophomonas maltophilia and Elizabethkingia anophelis.

PURPOSE OF REVIEW: This systematic review aimed to explore the recent trends in the epidemiology, risk factors, and antimicrobial susceptibility of two emerging opportunistic pathogens, Stenotrophomonas maltophilia and Elizabethkingia anophelis . RECENT FINDINGS: Since 2020, numerous outbreaks of S. maltophilia and E. anophelis have been reported worldwide. Most of these outbreaks have been associated with healthcare facilities, although one outbreak caused by E. anophelis in France was considered a community-associated infection. In terms of antimicrobial susceptibility, trimethoprim/sulfamethoxazole (TMP-SMZ), levofloxacin, and minocycline have exhibited good efficacy against S. maltophilia . Additionally, cefiderocol and a combination of aztreonam and avibactam have shown promising results in in vitro susceptibility testing. For E. anophelis , there is currently no consensus on the optimal treatment. Although some studies have reported good efficacy with rifampin, TMP-SMZ, piperacillin/tazobactam, and cefoperazone/sulbactam, minocycline had the most favourable in vitro susceptibility rates. Cefiderocol may serve as an alternative due to its low minimum inhibitory concentration (MIC) against E. anophelis . The role of vancomycin in treatment is still uncertain, although several successful cases with vancomycin treatment, even with high MIC values, have been reported. SUMMARY: Immunocompromised patients are particularly vulnerable to infections caused by S. maltophilia and E. anophelis , but the optimal treatment strategy remains inconclusive. Further research is necessary to determine the most effective use of conventional and novel antimicrobial agents in combatting these multidrug-resistant pathogens.

The protective effect of low-dose minocycline on brain microvascular ultrastructure in a rodent model of subarachnoid hemorrhage.

The multifaceted nature of subarachnoid hemorrhage (SAH) pathogenesis is poorly understood. To date, no pharmacological agent has been found to be efficacious for the prevention of brain injury when used for acute SAH intervention. This study was undertaken to evaluate the beneficial effects of low-dose neuroprotective agent minocycline on brain microvascular ultrastructures that have not been studied in detail. We studied SAH brain injury using an in vivo prechiasmatic subarachnoid hemorrhage rodent model. We analyzed the qualitative and quantitative ultrastructural morphology of capillaries and surrounding neuropil in the rodent brains with SAH and/or minocycline administration. Here, we report that low-dose minocycline (1 mg/kg) displayed protective effects on capillaries and surrounding cells from significant SAH-induced changes. Ultrastructural morphology analysis revealed also that minocycline stopped endothelial cells from abnormal production of vacuoles and vesicles that compromise blood-brain barrier (BBB) transcellular transport. The reported ultrastructural abnormalities as well as neuroprotective effects of minocycline during SAH were not directly mediated by inhibition of MMP-2, MMP-9, or EMMPRIN. However, SAH brain tissue treated with minocycline was protected from development of other morphological features associated with oxidative stress and the presence of immune cells in the perivascular space. These data advance the knowledge on the effect of SAH on brain tissue ultrastructure in an SAH rodent model and the neuroprotective effect of minocycline when administered in low doses.

Minocycline Protects Against Lipopolysaccharide-Induced Cognitive Impairment and Oxidative Stress: Possible Role of the CREB-BDNF Signaling Pathway.

The oxidative stress-induced dysregulation of the cyclic AMP response element-binding protein- brain-derived neurotrophic factor (CREB-BDNF) cascade has been linked to cognitive impairment in several studies. This study aimed to investigate the effect of minocycline on the levels of oxidative stress markers, CREB, and BDNF in lipopolysaccharide (LPS)-induced cognitive impairment. Fifty adult male Sprague Dawley rats were divided randomly into five groups. Group 1 was an untreated control group. Groups 2, 3, 4 and 5 were treated concurrently with LPS (5 mg/kg, i.p) once on day 5 and normal saline (0.7 ml/rat, i.p) or minocycline (25 and 50 mg/kg, i.p) or memantine (10 mg/kg, i.p) once daily from day 1 until day 14, respectively. From day 15 to day 22 of the experiment, Morris Water Maze (MWM) was used to evaluate learning and reference memory in rats. The levels of protein carbonyl (PCO), malondialdehyde (MDA), catalase (CAT), and superoxide dismutase (SOD) were determined by enzyme-linked immunosorbent assay (ELISA). CREB and BDNF expression and density were measured by immunohistochemistry and western blot analysis, respectively. LPS administration significantly increased escape latency to the hidden platform with decreased travelled distance, swimming speed, target crossings and time spent in the target quadrant. Besides, the hippocampal tissue of LPS rats showed increased levels of PCO and MDA, decreased levels of CAT and SOD, and reduced expression and density of BDNF and CREB. Treatment with minocycline reversed these effects in a dose-dependent manner, comparable to the effects of memantine. Both doses of minocycline treatment protect against LPS-induced cognitive impairment by reducing oxidative stress and upregulating the CREB-BDNF signalling pathway in the rat hippocampus.

Prevention of Postoperative Cognitive Dysfunction by Minocycline in Elderly Patients after Total Knee Arthroplasty: A Randomized, Double-blind, Placebo-controlled Clinical Trial.

BACKGROUND: There are no effective pharmacologic interventions for preventing postoperative cognitive dysfunction in daily practice. Since the antibiotic minocycline is known to suppress postoperative neuroinflammation, this study hypothesized and investigated whether minocycline might have a preventive effect on postoperative cognitive dysfunction after noncardiac surgery. METHODS: This study included patients aged more than 60 yr undergoing total knee arthroplasty under general anesthesia. They were randomly assigned to minocycline and placebo groups, to orally receive 100 mg of minocycline or placebo twice daily from the day before surgery until the seventh day after surgery. Cognitive function was evaluated before surgery, and 1 week and 3 months after surgery, using a battery of four cognitive function tests, including Visual Verbal Learning Test, Trail Making Test, Stroop Color and Word Test, and Letter-Digit Coding Task. Additionally, 30 healthy volunteers were subjected to the same tests as the patients to examine the learning effect of repeated tests. The occurrence of postoperative cognitive dysfunction was judged from the results of the neurocognitive test battery, with consideration of the learning effect. The secondary endpoints were the effects of minocycline on postoperative delirium and postoperative pain. RESULTS: A total of 100 patients were randomized to the minocycline group, and 102 were randomized to the placebo group. The average age of patients was 75 yr. Evaluation showed no significant difference in the incidence of postoperative cognitive dysfunction between the minocycline and placebo groups at both 1 week (8 of 90 [8.9%] vs. 4 of 95 [4.2%]; odds ratio, 2.22 [95% CI, 0.64 to 7.65]; P = 0.240) and 3 months (15.3 of 90 [17.0%] vs. 15.3 of 95 [16.1%]; odds ratio, 1.07 [95% CI, 0.49 to 2.32]; P = 0.889) postoperatively. Missing data 3 months after surgery were corrected by the multiple imputation method. There were no differences between the two groups in postoperative delirium and postoperative pain. CONCLUSIONS: Minocycline is likely to have no preventive effect on postoperative cognitive dysfunction.

Effect of minocycline, methyl prednisolone, or combination treatment on the colonic bacterial population in a state of colonic inflammation using the murine dextran sulfate sodium model.

BACKGROUND: Several reports demonstrated anti-inflammatory properties of minocycline in various inflammatory disorders including colitis. We have experimental evidence suggesting synergistic anti-inflammatory effect of minocycline with methyl prednisolone in reducing colitis severity in mice, but if this effect is in part related to modulating the composition of colonic microbiota is still unknown. METHODS: the effect of vehicle (V), minocycline (M), methyl prednisolone (MP), or combination (C) regimen on the composition of the microbiota of mice in a state of colon inflammation compared to untreated (UT) healthy mice was determined using 16s metagenomic sequencing, and the taxonomic and functional profiles were summarized. RESULTS: Overall, the bacterial flora from the phylum Firmicutes followed by Bacteroidota were found to be predominant in all the samples. However, the composition of Firmicutes was decreased relatively in all the treatment groups compared to UT group. A relatively higher percentage of Actinobacteriota was observed in the samples from the C group. At the genus level, Muribaculaceae, Bacteroides, Bifidobacterium, and Lactobacillus were found to be predominant in the samples treated with both drugs (C). Whereas "Lachnospiraceae NK4A136 group" and Helicobacter in the M group, and Helicobacter in the MP group were found to be predominant. But, in the UT group, Weissella and Staphylococcus were found to be predominant. Eubacterium siraeum group, Clostridia vadinBB60 group, Erysipelatoclostridium and Anaeroplasma genera were identified to have a significant (FDR p < 0.05) differential abundance in V compared to C and UT groups. While at the species level, the abundance of Helicobacter mastomyrinus, Massiliomicrobiota timonensis and uncultured Anaeroplasma were identified as significantly low in UT, C, and M compared to V group. Functional categories related to amino acid, carbohydrate, and energy metabolism, cell motility and cell cycle control were dominated overall across all the samples. Methane metabolism was identified as an enriched pathway. For the C group, "Colitis (decrease)" was among the significant (p = 1.81E-6) associations based on the host-intrinsic taxon set. CONCLUSION: Combination regimen of minocycline plus methyl prednisolone produces a synergistic anti-inflammatory effect which is part related to alternation in the colonic microbiota composition.

Enhanced bacterial killing with a combination of sulbactam/minocycline against dual carbapenemase-producing Acinetobacter baumannii.

Carbapenem-resistant Acinetobacter baumannii (CRAB) is often difficult to treat. Considering the current circumstances, there is an unquestionable need for new therapeutic options to treat CRAB infections. In the present study, the synergistic activity of sulbactam-based combination was determined against genetically characterized CRAB isolates. Non-duplicate CRAB isolates (n = 150) recovered from blood culture and endotracheal aspirates were included in this study. The minimum inhibitory concentrations (MICs) of tetracyclines (minocycline, tigecycline, eravacycline) and their comparators (meropenem, sulbactam, cefoperazone/sulbactam, ceftazidime/avibactam, and colistin) were determined using the microbroth dilution method. Six isolates were tested for the synergistic activity of various sulbactam-based combinations using time-kill experiments. Tigecycline and minocycline showed a wide spread of MICs with most isolates in the range of 1 to 16 mg/L. The MIC90 of eravacycline (0.5 mg/L) was four dilutions lower than that of tigecycline (8 mg/L). Minocycline with sulbactam was the most active dual combination against OXA-23 like (n = 2) and NDM with OXA-23 like producers (n = 1), which resulted in ≥ 2 log10 kill. The combination of ceftazidime-avibactam with sulbactam showed ≥ 3 log10 kill against all the three tested OXA-23 like producing CRAB isolates, but showed no activity against dual carbapenemase producers. Sulbactam with meropenem showed ≥ 2 log10 kill against one OXA-23 like producing CRAB isolate. The findings suggest that sulbactam-based combination may confer therapeutic benefits against CRAB infections.

New regimens as first-line eradication therapy for Helicobacter pylori infection in patients allergic to penicillin: A randomized controlled trial.

BACKGROUND: Helicobacter pylori eradication in penicillin-allergic patients is challenging. The effective regimen is lacking in areas with high antibiotic resistance and tetracycline unavailable. Minocycline, cefuroxime, and full-dose metronidazole are promising drugs. AIMS: To compare the eradication rate, safety, and compliance among three new bismuth quadruple therapies for first-line H. pylori eradication in penicillin-allergic patients. METHODS: This randomized trial was conducted on 450 naive patients with H. pylori infection and penicillin allergy. The 14-day minocycline-metronidazole-containing (minocycline 100 mg twice daily and metronidazole 400 mg four times/day), minocycline-cefuroxime-containing (minocycline 100 mg twice daily and cefuroxime 500 mg twice daily), and cefuroxime-metronidazole-containing (cefuroxime 500 mg twice daily and metronidazole 400 mg four times/day) bismuth quadruple therapies were randomly assigned to the participants. Safety and compliance were assessed within 3 days after eradication. Urea breath test was performed 4-8 weeks after eradication to evaluate outcome. RESULTS: The differences of eradication rates in either intention-to-treat (84.0%, 82.7%, and 23 82.0%, p = .896) or per-protocol (91.7%, 90.9%, and 88.2%, p = .599) analysis among minocycline-metronidazole, minocycline-cefuroxime, and cefuroxime-metronidazole-containing bismuth quadruple therapies were statistically insignificant. The incidence of adverse events (35.1%, 22.6%, and 28.9%) and compliance (90.5%, 91.8%, and 91.9%) were similar. Taste distortion, nausea, and anorexia were more common in metronidazole-containing regimens, and dizziness was more common in minocycline-containing regimens. The allergy was rare (~3%). CONCLUSIONS: The efficacies of three bismuth quadruple therapies containing minocycline, cefuroxime, and full-dose metronidazole (pairwise) for first-line H. pylori eradication in penicillin-allergic patients were similarly satisfactory with relatively good safety and compliance. The study was registered in the Chinese Clinical Trials Registration (ChiCTR1900023702).