Low-dose Treatment Research Articles

Is there still a place for etomidate in the management of Cushing's syndrome? The experience of a single center of low-dose etomidate and combined etomidate-osilodrostat treatment in severe hypercortisolemia.

Severe Cushing's syndrome (SCS) is a life-threatening endocrine condition that requires prompt medical intervention. Intravenous etomidate infusion is considered to be the most effective in rapid cortisol overproduction inhibition. This single-center retrospective study aimed to present the safety and effectiveness of intravenous, low-dose, lipid-formulated etomidate infusion in patients with SCS. Seven patients with complicated SCS related to ectopic ACTH syndrome (n = 6) or Cushing's disease (n = 1) who received low-dose etomidate infusion as a part of their cortisol-lowering treatment between April 2019 and April 2024 in the Department of Internal Medicine, Endocrinology and Diabetes of Medical University of Warsaw were included in the study. A continuous etomidate infusion was initiated at 0.01-0.02 mg/kg/h. In all patients, rapid control of hypercortisolemia was achieved with a median time of 30 h (range: 12-48 h). Median serum cortisol concentration reduced from 101.9 μg/dL (range: 78.2-119.6 μg/dL) before etomidate to 19.5 μg/dL (range: 18.3-22.5) after 72 h of etomidate treatment. Etomidate infusion was followed by etomidate and osilodrostat combined treatment and then osilodrostat monotherapy in four patients; one patient underwent adrenalectomy, and two patients died during etomidate infusion due to complications of advanced malignancy. This study shows that low-dose and short-term lipid formulation etomidate therapy is highly effective in severe hypercortisolemia management. Combined therapy with etomidate and osilodrostat is well tolerated and could serve as a bridge in long-term SCS treatment.

16S rRNA Sequencing Analysis Uncovers Dose-Dependent Cupric Chloride Effects on Silkworm Gut Microbiome Composition and Diversity

Copper-based pesticides are extensively used in agriculture, yet their impacts on beneficial insects remain poorly understood. Here, we investigate how cupric chloride exposure affects the gut microbiome of Bombyx mori, a model organism crucial for silk production. Using 16S rRNA sequencing, we analyzed the gut bacterial communities of fifth-instar silkworm larvae exposed to different concentrations of cupric chloride (0, 4, and 8 g/kg) in an artificial diet. The high-dose exposure dramatically altered the microbial diversity and community structure, where the Bacteroidota abundance decreased from 50.43% to 23.50%, while Firmicutes increased from 0.93% to 18.92%. A network analysis revealed complex interactions between the bacterial genera, with Proteobacteria and Firmicutes emerging as key players in the community response to copper stress. The functional prediction indicated significant shifts in metabolic pathways and genetic information processing in the high-dose group. Notably, the low-dose treatment induced minimal changes in both the taxonomic composition and predicted functions, suggesting a threshold effect in the microbiome response to copper exposure. Our findings provide novel insights into how agricultural chemicals influence insect gut microbiota and highlight potential implications for silkworm health and silk production. This work contributes to understanding the ecological impacts of copper-based pesticides and may inform evidence-based policies for their use in sericulture regions.

Low-dose heparin sodium as a protective factor against bronchiolitis obliterans formation after adenovirus infection

Background Adenovirus (ADV) pneumonia in children is a significant contributor to the occurrence of post-infectious bronchiolitis obliterans (BO). Heparin sodium has known anti-inflammatory, immunomodulatory, and tissue repair properties. However, its role in treating BO after ADV infection remains unclear. Methods A retrospective analysis was conducted on 793 children diagnosed with ADV pneumonia and hospitalized in the southern region from January 2019 to December 2019. Among them, 307 cases were classified as single ADV pneumonia. We utilized directed acyclic graphs to analyze the causal relationships between various variables, which further helped us identify the independent and confounding variables for constructing our regression model. Propensity score matching (PSM) was also employed to control for confounding variables that could not be intervened in this study, ensuring baseline level equilibrium and correction. We utilized univariate logistic regression analysis to explore the factors influencing BO development after ADV pneumonia. Results Among the 793 children diagnosed with ADV pneumonia, 86 cases (10.84%) progressed to BO. The proportion of heparin use was higher in the non-BO group than in the BO group after PSM. The univariate regression analysis revealed that acute respiratory failure, neurological involvement and fibrinogen (FIB) were risk factors for the development of BO in ADV pneumonia cases (OR > 1, p < 0.05), but low-dose heparin sodium treatment and hemoglobin (OR < 1, p < 0.05) exhibited protective effects against BO formation. Among the 307 children with single ADV pneumonia (excluding confounding factors), 33 cases (10.75%) developed BO. The univariate regression analysis further indicated that fever duration, acute respiratory failure and FIB were risk factors for the development of BO in single ADV pneumonia (OR > 1, p < 0.05), while low-dose heparin sodium treatment (OR < 1, p < 0.05) was protective against BO formation after a single ADV pneumonia. Conclusion Low-dose heparin sodium treatment may be a protective factor against the development of BO after ADV pneumonia infection.

The effect of acetylcholinesterase inhibitor rivastigmine in pentylenetetrazole-induced kindling model of epilepsy in rats.

This study aimed to investigate the role of acetylcholinesterase (AChE) and butyrylcholinesterase (BuChE) inhibitor rivastigmine (RIVA) in the pentylenetetrazole (PTZ)- induced kindling model of epilepsy. The current study consists of three steps; 1) Saline or RIVA (0.5, 1, and 2 mg/kg) was administered intraperitoneally (i.p.) 15 min before PTZ (35 mg/kg) during the kindling process and seizure behaviors were observed; 2) Single doses of RIVA (0.25, 0.5, and 1 mg/kg; i.p.) was administered to the electrode implanted kindled rats 15 min before PTZ and electrocorticogram (ECoG) recordings were obtained; 3) Low-dose of RIVA (0.5 mg/kg) was administered to the kindled rats for 14 consecutive days and after 24 h PTZ was administered and ECoG recordings were obtained. In addition, 24 h after the PTZ injection, the hippocampus was extracted and mRNA expression levels of N-methyl D-aspartate receptor subunit 2B (NR2B) and brain-derived neurotrophic factor (BDNF) were measured by qPCR analysis. Only low-dose of RIVA increased resistance against kindling. Single and long-term administration of low-dose RIVA increased the latency to the first myoclonic jerk, decreased the duration of generalized tonic-clonic seizures, and reduced the seizure stage in kindled rats. Long-term low-dose RIVA treatment decreased the mRNA expressions of NR2B and BDNF, which were increased after PTZ kindling. Low-dose of RIVA showed anticonvulsant properties, while high doses did not. RIVA exerts its anticonvulsant effect probably through NMDAR-BDNF pathways. Our results suggest that the use of RIVA may not be harmful and even reduce seizure severity in epileptic patients with convulsions.

Impact of Therapeutic Doses of Prednisolone and Other Glucocorticoids on Insulin Secretion from Human Islets

Glucocorticoid-induced diabetes (GCID) is a prevalent health issue, generally attributed to insulin resistance. High doses of dexamethasone (DEX) are known to inhibit glucose-stimulated insulin secretion (GSIS), but the effects of lower doses, commonly used in chronic therapy, and equipotent doses of other glucocorticoids (GCs) such as hydrocortisone (HC) and prednisone (PRED) remain underexplored. This study aimed to investigate these effects in vitro, and explore variations between patients. Dynamic perifusion assays were conducted on human islets to evaluate the impact of different GCs on GSIS. The islets were treated for 24h with 250 nM PRED and other GCs at equipotent anti-inflammatory doses (HC: 1 µM; DEX: 38 nM). In 11 human islet donor preparations, 250 nM PRED, corresponding to a clinical oral dose of 5mg/day, significantly inhibited the first and second phase of GSIS: area under the curve (AUC) decreased by 32.3% (p < 0.001), first phase by 41.5% (p < 0.001), and second phase by 38.4% (p < 0.001). Despite interindividual differences in GSIS response to PRED, no significant differences were observed according to body-mass index, gender or age. Comparing the effects of GCs at equipotent anti-inflammatory doses, DEX had a more pronounced inhibitory effect on GSIS than HC or PRED. In vitro, low-dose PRED treatment significantly impacted GSIS. DEX had a more unfavorable impact on GSIS than HC or PRED, indicating that metabolic effects do not align with anti-inflammatory potency.

Lily extract ameliorate mouse pneumonia by modulating ciliary function

This study explores the biological effects and mechanisms of Lily extract on LPS-induced pneumonia mice. Research has found that after 48 h of treatment with low-dose and high-dose lily extract (100 mg/kg, 200 mg/kg), there was a significant reduction in inflammatory cell infiltration, mRNA expression levels of pro-inflammatory factors (IL-6, IL-1β, TNF-α), protein levels of inflammation-related proteins (IL-6, NF-κB P65) in the lung tissue. In addition, lily extract significantly improved the function of cilia assembly and movement. The expression levels of cilia-related genes (Ttc21a, Cfap45, etc.) and proteins were significantly upregulated. Among them, the high-dose treatment group had tightly arranged cilia and good growth conditions, which was significantly better than the LPS pneumonia model and low-dose treatment group. This found providing novel insights into the pathogenesis and progression of pneumonia. This has important implications for the prevention and treatment of pneumonia, as well as the development of natural agents.

Low-dose tamoxifen treatment reduces collagen organisation indicative of tissue stiffness in the normal breast: results from the KARISMA randomised controlled trial.

Tissue stiffness, dictated by organisation of interstitial fibrillar collagens, increases breast cancer risk and contributes to cancer progression. Tamoxifen is a standard treatment for receptor-positive breast cancer and is also aproved for primary prevention. We investigated the effect of tamoxifen and its main metabolites on the breast tissue collagen organisation as a proxy for stiffness and explored the relationship between mammographic density (MD) and collagen organisation. This sub-study of the double-blinded dose-determination trial, KARISMA, included 83 healthy women randomised to 6months of 20, 10, 5, 2.5, and 1mg of tamoxifen or placebo. Ultrasound-guided core-needle breast biopsies collected before and after treatment were evaluated for collagen organisation by polarised light microscopy. Tamoxifen reduced the amount of organised collagen and overall organisation, reflected by a shift from heavily crosslinked thick fibres to thinner, less crosslinked fibres. Collagen remodelling correlated with plasma concentrations of tamoxifen metabolites. MD change was not associated with changes in amount of organised collagen but was correlated with less crosslinking in premenopausal women. In this study of healthy women, tamoxifen decreased the overall organisation of fibrillar collagens, and consequently, the breast tissue stiffness. These stromal alterations may play a role in the well-established preventive and therapeutic effects of tamoxifen. Trial registration ClinicalTrials.gov ID: NCT03346200. Registered November 1st, 2017. Retrospectively registered.

A Combined Extract Derived from Black Sticky Rice and Dill Improves Clinical Symptoms and Ischemic Stroke Biomarkers in Transient Ischemic Attack and Ischemic Stroke Patients.

Currently, the adjuvant therapy to optimize the restorative process after stroke is required due to the unsatisfied therapeutic efficacy. A combined extract of black sticky rice and dill showed potential in the preclinical state, so we hypothesized that it could provide clinical benefits. A three-arm, randomized, placebo-controlled study was set up to elucidate this issue. Both males and females (18-80 years old) who had experienced transient ischemic attacks or ischemic strokes within the last 5-10 days with an NIHSS score ≤ 7 and received standard treatment were randomly assigned to receive either a placebo or capsule containing a combined extract of black sticky rice and dill at a dose of 600 or 1200 mg per day. The safety parameters, movement control, and degree of disability were assessed 1, 2, and 6 weeks after the intervention, and serum stroke biomarkers were assessed at the mentioned time points, except at 2 weeks. After week 1, the high-dose (1200 mg/day) treatment group had improved NIHSSS, VCAM1, and MMP-9. Both S100β and VCAM1 also improved at week 6, while the low-dose treatment group (600 mg/day) only exhibited improved VCAM1. Therefore, a high dose of the developed adjuvant supplement improves stroke recovery by improving motor impairment by reducing endothelial dysfunction and inflammation.

Microtubule poleward flux as a target for modifying chromosome segregation errors

Cancer cells often display errors in chromosome segregation, some of which result from improper chromosome alignment at the spindle midplane. Chromosome alignment is facilitated by different rates of microtubule poleward flux between sister kinetochore fibers. However, the role of the poleward flux in supporting mitotic fidelity remains unknown. Here, we introduce the hypothesis that the finely tuned poleward flux safeguards against lagging chromosomes and micronuclei at mitotic exit by promoting chromosome alignment in metaphase. We used human untransformed RPE-1 cells depleted of KIF18A/kinesin-8 as a system with reduced mitotic fidelity, which we rescued by three mechanistically independent treatments, comprising low-dose taxol or codepletion of the spindle proteins HAUS8 or NuMA. The rescue of mitotic errors was due to shortening of the excessively long overlaps of antiparallel microtubules, serving as a platform for motor proteins that drive the flux, which in turn slowed down the overly fast flux and improved chromosome alignment. In contrast to the prevailing view, the rescue was not accompanied by reduction of overall microtubule growth rates. Instead, speckle microscopy revealed that the improved chromosome alignment in the rescue treatments was associated with slower growth and flux of kinetochore microtubules. In a similar manner, a low-dose taxol treatment rescued mitotic errors in a high-grade serous ovarian carcinoma cell line OVKATE. Collectively, our results highlight the potential of targeting microtubule poleward flux to modify chromosome instability and provide insight into the mechanism through which low doses of taxol rescue certain mitotic errors in cancer cells.

IMMU-60. MYELOID POPULATIONS MODULATE GD2 CAR T CELL ACTIVITY IN DIFFUSE MIDLINE GLIOMA

Abstract H3K27M-mutated diffuse midline gliomas (DMGs) are universally lethal cancers in children and young adults. Our team previously demonstrated efficacy of GD2-targeting chimeric antigen receptor T cells (GD2-CAR T-cells) in preclinical models of DMG of the pons (also called diffuse intrinsic pontine glioma (DIPG) and DMG of the spinal cord, and opened a Phase I clinical trial (NCT04196413) treating patients with first intravenous (IV) followed by repeated infusions of intracerebroventricular (ICV) GD2-CAR T-cells. We employed high-dimensional analyses to define immune states contributing to CAR-T activity in patients. Single cell RNA-sequencing (scRNAseq) was conducted on 555,406 single cells from 115 cerebrospinal fluid (CSF) samples of 13 patients before and after CAR-T treatment. This is the largest CSF CAR-T dataset in central nervous system (CNS) tumors and provides insights into the immune biology surrounding CAR-T treatment for CNS malignancies. Patient CSF samples were dominated by T cell and myeloid populations. After CAR-T infusion, patient CSF exhibited an increased fraction of regulatory T cells and myeloid populations from baseline. Myeloid cells in early timepoints after ICV administration demonstrated a unique pro-inflammatory signature, while CSF samples from IV and late ICV timepoints exhibited a suppressive signature. To further explore the immune biology of these myeloid contributors, we developed a patient-derived xenograft model of DMG relapse following low-dose ICV GD2 CAR-T treatment. Using a pharmacological CSF1R-inhibitor, we demonstrate that depletion of microglia/myeloid cells at a specific window following CAR-T administration enhances durability of tumor control. Together, these data display the power of in-depth correlative analyses to identify distinct immune populations that drive durability of response. Key findings from these data will allow for optimization of CAR-T therapies for H3K27M+ DMG patients, providing hope to shift the paradigm of this fatal disease.

Diagnostic utility of testosterone priming prior to dynamic tests to differentiate constitutional delay in puberty from isolated hypogonadotropic hypogonadism in boys

BackgroundDifferentiation between isolated hypogonadotropic hypogonadism (IHH) and constitutional delay in puberty (CDP) throughout adolescence can be challenging for doctors. This study examines the withdrawal effects of short-term, low-dose testosterone treatment (testosterone priming) on the ability of dynamic testing to distinguish between CDP and IHH based on activation of the hypothalamo-pituitary–testicular axis.MethodsA case–control study included 20 boys with delayed puberty (group A) and 20 patients with IHH (group B). Both groups underwent Triptorelin and human chorionic gonadotropin (hCG) stimulation tests before and 2 months after testosterone injections (100 mg) intramuscularly every 4 weekly for 3 months.ResultsThe triptorelin-stimulated 4-h LH with a cutoff of 2.4 IU/L and the hCG-stimulated testosterone with a cutoff of 1.160 ng/mL had sensitivities of 65% each, and specificities of 90% and 95%, respectively, to diagnose CDP. After testosterone withdrawal, the cut-off values for 4-h LH were 8.850 IU/L and 3.190 ng/mL for hCG-stimulated testosterone. Basal inhibin B > 88.25 pg/ml was found to be a differentiating factor in diagnosing CDP after testosterone withdrawal.Conclusionsfollowing the withdrawal of testosterone therapy, Inhibin B levels or 4-h stimulated LH are the most effective discriminant assays to distinguish CDP from IHH.

Replication stress induces POLQ-mediated structural variant formation throughout common fragile sites after entry into mitosis

Genomic structural variants (SVs) greatly impact human health, but much is unknown about the mechanisms that generate the largest class of nonrecurrent alterations. Common fragile sites (CFSs) are unstable loci that provide a model for SV formation, especially large deletions, under replication stress. We study SV junction formation as it occurs in human cell lines by applying error-minimized capture sequencing to CFS DNA harvested after low-dose aphidicolin treatment. SV junctions form throughout CFS genes at a 5-fold higher rate after cells pass from G2 into M-phase. Neither SV formation nor CFS expression depend on mitotic DNA synthesis (MiDAS), an error-prone form of replication active at CFSs. Instead, analysis of tens of thousands of de novo SV junctions combined with DNA repair pathway inhibition reveal a primary role for DNA polymerase theta (POLQ)-mediated end-joining (TMEJ). We propose an important role for mitotic TMEJ in nonrecurrent SV formation genome wide.

Peripapillary hyperreflective ovoid mass-like structure (PHOMS): prevalence, risk factors, and development over time in Danish myopic children

BackgroundOn optical coherence tomography (OCT) scans of the optic nerve head, peripapillary hyperreflective ovoid mass-like structures (PHOMS) are sometimes seen as a sign of axonal distension. The phenomenon has been reported more frequently in myopic subjects. We investigated PHOMS-prevalence in a myopic pediatric cohort, associated risk factors, and PHOMS development over 18 months during low-dose atropine treatment. MethodsIn this post hoc analysis of an investigator-initiated, placebo-controlled, randomized clinical trial, 97 6- to 12-year-old myopic participants were randomized to 0.1% atropine for 6 months, then 0.01% for 18 months (N = 33), 0.01% for 24 months (N = 32) or placebo for 24 months (N = 32). Primary outcome was presence of PHOMS. Secondary outcome was mean nasal PHOMS diameter measured on OCT B-scan. Outcomes were reported at baseline, 6, and 18 months. Logistic regression and linear mixed modelling were performed. ResultsPHOMS were present in 26% of participants (n = 25), and 52% (n = 13) had bilateral presentation. Optic disk tilt (OR = 10.81; 95% CI, 3.58-32.58 [P < 0.001]) and longer axial length (AL) (OR = 2.06; 95% CI, 1.02-4.17 [P = 0.04]) increased the risk of having PHOMS. Greater increase in nasal peripapillary choroidal thickness over time was associated with smaller PHOMS diameter at 18 months (P = 0.05). ConclusionsPHOMS were common in our cohort of children with myopia. Longer AL increases the risk of, but not size of, PHOMS. The diameter of PHOMS seemed stable over time and unaffected by low-dose atropine.

IL-21/IL-21R signaling renders acute myeloid leukemia stem cells more susceptible to cytarabine treatment and CAR T cell therapy

Self-renewal programs in leukemia stem cells (LSCs) predict poor prognosis in patients with acute myeloid leukemia (AML). We identify CD4+ Tcell-derived interleukin (IL)-21 as an important negative regulator of self-renewal of LSCs. IL-21/IL-21R signaling favors asymmetric cell division and differentiation in LSCs through the activation of p38-MAPK signaling, resulting in reduced LSC numbers and significantly prolonged survival in murine AML models. In human AML, serum IL-21 at diagnosis is identified as an independent positive prognostic biomarker for outcome and correlates with improved survival and higher complete remission rates in patients that underwent high-dose chemotherapy. IL-21 treatment inhibits primary LSC function and enhances the effect of cytarabine and CD70 CAR Tcell treatment on LSCs invitro. Low-dose IL-21 treatment prolongs the survival of AML mice in syngeneic and xenograft experiments. Therefore, promoting IL-21/IL-21R signaling on LSCs may be an approach to reduce stemness and increase differentiation in AML.

The Combined Inhibition of SREBP and mTORC1 Signaling Synergistically Inhibits B-Cell Lymphoma.

The sterol regulatory element-binding protein (SREBP) pathway is essential for maintaining sterol homeostasis during B cell activation and germinal center B cell proliferation. However, its potential as a therapeutic target to treat B-cell lymphoma remains unclear. We examined SREBP protein expression in human B-cell lymphoma samples using immunohistochemistry. Additionally, we conducted invitro studies using SREBP signaling inhibitors in combination with rapamycin to assess their effects on cell proliferation and lipid metabolism in B-cell lymphoma cells. Our analysis revealed high levels of SREBP2 protein expression in human B-cell lymphoma samples. Inhibiting SREBP signaling or its downstream target HMG-CoA reductase (HMGCR) with Fatostatin or Simvastatin effectively suppressed B-cell lymphoma cell proliferation. However, B-cell lymphoma cells responded to statin treatment by activating the mTORC1-pS6 pathway, suggesting a compensatory mechanism to overcome statin-induced cell cycle arrest. Combining low-dose statin treatment with the mTOR inhibitor rapamycin produced a synergistic effect, significantly inhibiting B-cell lymphoma proliferation, cell cycle progression, and lipid raft formation. These results highlight the potential of a combined therapeutic approach targeting both SREBP and mTORC1 as a novel strategy for treating B-cell lymphoma.

Oral low-dose rapamycin treatment prevents aortic aneurysms in marfan mice

Abstract Background/Introduction Marfan syndrome (MFS) is a hereditary connective tissue disorder caused by fibrillin-1 (FBN1) gene mutations. Life-threatening complications are cardiovascular, e.g. thoracic aortic aneurysms and dissections. The pathophysiological cause is the increased release of transforming growth factor β-1 (TGF-β1) from the FBN1-deficient extracellular matrix (ECM) and structural disintegrity. Overactivation of the mechanistic target of rapamycin (mTOR) pathway has been demonstrated in the murine mgR/mgR model of MFS. Short-term administration of rapamycin significantly reduced aortic aneurysm formation and increased the life span in these mice. Purpose To assess the effect of an early continuous oral low-dose rapamycin treatment on the aortic aneurysm formation in the FBN1 hypomorphic mgR/mgR mouse model. Methods Male and female 3-4 week-old mgR/mgR mice were orally administered vehicle or rapamycin through diet (8mg/kg/KG) and sacrificed after 11 weeks. Rapamycin concentration was measured by liquid chromatography-mass spectrometry in whole blood. Aortic diameter was studied using echocardiography. Histopathological and immunofluorescence analyses were performed using aortic tissue sections and techniques. Results Blood rapamycin concentration following oral administration remained below detection level. Rapamycin normalized the aortic wall thickness and the diameter in female mgR/mgR mice to levels of the littermate control mice but not in male mgR/mgR mice. The circumferentially distributed elastin fibres remained significantly intact in sections of the ascending aorta of female mice. Echocardiography revealed that rapamycin-treated female mice stayed below a cut-off value for aortic aneurysms of 2 mm inner aortic diameter eight weeks after starting therapy. In contrast, vehicle-treated female animals already exceeded this value after five weeks. In female but not in male mice, the abundance of the mTOR downstream target phosphorylated ribosomal protein S6 was effectively suppressed by low-dose rapamycin up to levels detected in control animals. At the same time, extracellular matrix proteins like the proteoglycan aggrecan (ACAN) and the related chondroitin sulfate were significantly decreased in female mice. The abundance of ADAMTS5 transglutaminase-2 and xylosyltransferase-1, key enzymes involved in the turnover of proteoglycans and biosynthesis of glycosaminoglycan chains, was improved by the rapamycin treatment in female mice. No decrease in mTOR activity could be detected in male mgR/mgR animals. Here, the ACAN and chondroitin sulphate levels also remained at the level of the vehicle-treated animals. Conclusions Chronic low-dose rapamycin treatment reduced aneurysm formation only in female mgR/mgR mice, since the dose was too low for male mgR/mgR mice, by affecting the composition and organization of key ECM components essential for maintaining aortic homeostasis and mechanical properties.

Long-term reprogramming of primed microglia after moderate inhibition of CSF1R signaling.

In acute neuroinflammation, microglia activate transiently, and return to a resting state later on. However, they may retain immune memory of such event, namely priming. Primed microglia are more sensitive to new stimuli and develop exacerbated responses, representing a risk factor for neurological disorders with an inflammatory component. Strategies to control the hyperactivation of microglia are, hence, of great interest. The receptor for colony stimulating factor 1 (CSF1R), expressed in myeloid cells, is essential for microglia viability, so its blockade with specific inhibitors (e.g. PLX5622) results in significant depletion of microglial population. Interestingly, upon inhibitor withdrawal, new naïve microglia repopulate the brain. Depletion-repopulation has been proposed as a strategy to reprogram microglia. However, substantial elimination of microglia is inadvisable in human therapy. To overcome such drawback, we aimed to reprogram long-term primed microglia by CSF1R partial inhibition. Microglial priming was induced in mice by acute neuroinflammation, provoked by intracerebroventricular injection of neuraminidase. After 3-weeks recovery, low-dose PLX5622 treatment was administrated for 12 days, followed by a withdrawal period of 7 weeks. Twelve hours before euthanasia, mice received a peripheral lipopolysaccharide (LPS) immune challenge, and the subsequent microglial inflammatory response was evaluated. PLX5622 provoked a 40%-50% decrease in microglial population, but basal levels were restored 7 weeks later. In the brain regions studied, hippocampus and hypothalamus, LPS induced enhanced microgliosis and inflammatory activation in neuraminidase-injected mice, while PLX5622 treatment prevented these changes. Our results suggest that PLX5622 used at low doses reverts microglial priming and, remarkably, prevents broad microglial depletion.

Unleashing the Power of Cold Atmospheric Plasma: Inducing Mitochondria Damage-Mediated Mitotic Catastrophe.

Despite the promise of cold atmospheric plasma (CAP) for cancer treatment, the challenges associated with the treatment of solid tumors and penetration depth limitations remain, restricting its clinical application. Here, biological evidence is provided that the killing effect of CAP treatment is confined to less than 500µm subcutaneously and the actual biological dose decreased gradually with depth for the first time, indicating that the limited penetration depth has become an urgent problem that demands immediate solutions. Significantly, it is showed that different from high-dose treatments, CAP decreased the doses to the low-dose range but still exhibited anti-tumor effects via mitotic catastrophe. Unlike radiotherapy or chemotherapy, low-dose CAP treatment induces mitochondrial structural damage and dysfunction, disrupts energy metabolism and redox balance, and results in mitotic catastrophe. Collectively, these findings suggest that better understanding and taking full advantage of the dose-response gradient effect of CAP is a potential strategy to prompt its clinical application beyond improving CAP penetration.

Therapeutic effects and mechanisms of Modified Ma-Xing-Shi-Gan Decoction on Klebsiella pneumoniae-induced pneumonia in mice assessed by Multi-omics

Ethnopharmacological relevanceModified Ma-Xing-Shi-Gan decoction (MMXSGD), a classic prescription from Treatise on Febrile Disease in China, is commonly used to treat Klebsiella pneumoniae (KP) infections in clinical settings. Materials and methodsThe aim of this study is to assess the efficacy of MMXSGD in the treatment of pneumonia and investigate its underlying mechanism of action. UHPLC-MS/MS was established to identify the main chemical components of serum after intragastric administration with MMXSGD. A mouse model of pneumonia caused by KP was used to evaluate the therapeutic potential of MMXSGD. The macrophage polarization was analyzed by immunohistochemistry. The cytokine profile was assessed using Luminex assay. Lung transcript and metabolite levels were assessed by transcriptomics and non-targeted metabolomics to analyze potential anti-pneumonia mechanisms and targets. Results22 major blood-entry components and 274 MMXSGD-pneumonia-related targets were identified. Compared with the model group, the mortality rate of mice in different dosage groups of MMXSGD was significantly reduced, and pathological lung damage was significantly alleviated. Among them, the low dose of MMXSGD treatment had the best protective effect. Further, MMXSGD treatment could regulates M1/M2 polarization in macrophages and inhibits the production of pro-inflammatory cytokines. The data from transcriptome and metabolome analysis indicate that MMXSGD could regulate inflammation-related pathways (PI3K/AKT, HIF-1, NF-κB pathway) and metabolites to modulate pulmonary inflammation. The results demonstrate that MMXSGD enhances the antibacterial effect in vivo by suppressing inflammation and regulating immunity rather than directly antibacterial effect. ConclusionThese findings provide a further assessment of MMXSGD, suggesting that MMXSGD has good therapeutic efficacy in bacterial infectious diseases.

The Macular Choroidal Thickness in Danish Children with Myopia After Two-Year Low-Dose Atropine and One-Year Wash-Out: A Placebo-Controlled, Randomized Clinical Trial.

Our aim in this work was to investigate the macular choroidal thickness (ChT) changes in 6-12-year-old Danish children with myopia during 2years of low-dose atropine treatment and 1-year wash-out vs. placebo in an investigator-initiated, placebo-controlled, double-blind randomized clinical trial. Ninety-seven participants wererandomized to either 0.01% for 2years, 0.1% loading dose for 6months followed by 0.01% for 18months, or placebo, then a 1-year wash-out. The primary outcome was ChT in the sub-foveal and inner and outer superior, nasal, inferior, and temporal sectors. The secondary outcome was axial length (AL). Outcomes were measured at baseline and 6, 12, 24, and 36 months. One-way analysis of variance was used to detect baseline ChT differences between AL-stratified groups (< 24mm, 24-25mm, or > 25mm). To determine the longitudinal changes in ChT and its effect on AL, all eyes were included in linear mixed modeling with individual eyes nested in the study ID as a random effect. Longer eyes had significantly thinner ChT in all choroidal sectors (adj-P < 0.01) at baseline. There was no statistically significant change in any ChT sector after 3years in the placebo group. Sub-foveal and nasal ChT in the 0.1% loading dose and 0.01% group were not significantly different from placebo after 2-year treatment. In the placebo group, a 1-mm increase in AL was significantly associated with a 47-µmthinner nasal ChT after 3years (95% confidence interval (CI): -55; -38, adj-P < 0.001). A 10-µmthicker nasal choroid at baseline was associated with 0.13 mm (95% CI: 0.009; 0.017, adj-P < 0.001) less 3-year axial elongation. The ChT in Danish children with myopia remained stable over the 3-year follow-up. A thinner choroid at myopia onset might predispose to increased axial elongation. Treatment with 0.01% atropine did not change the ChT. We speculate that low-dose atropine does not primarily reduce myopia progression via a choroidal mechanism. ClinicalTrials.gov identifier, NCT03911271.