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Alzheimer's disease (AD) is a complex neurocognitive disorder. Early theories of AD sought to identify a single unifying explanation underlying AD pathogenesis; however, evolving evidence suggests it is a multifactorial, systemic disease, involving multiple systems. Of note, vascular dysfunction, encompassing both cerebral and peripheral circulation, has been implicated in AD pathogenesis. This pilot study used intravital microscopy to assess differences in responsiveness of gluteal muscle arterioles between a transgenic AD mouse model (APP/PS1; Tg) and wild-type (C57BL/6; WT) mice to further elucidate the role of vascular dysfunction in AD. Arteriole diameters were measured in response to acetylcholine (10–9 to 10–5 M), phenylephrine (10–9 to 10–5 M), histamine (10–9 to 10–4 M) and compound 48/80 (10–9 to 10–3 M). Tg mice demonstrated a trend toward reduced vasodilatory response to acetylcholine with a significant difference at 10–5 M (36.91 vs. 69.55%: p = 0.0107) when compared to WT. No significant differences were observed with histamine, compound 48/80 or phenylephrine; however, a trend toward reduced vasoconstriction to phenylephrine was observed in Tg mice at higher concentrations. Mean net diameter change (resting to maximum) also differed significantly (p = 0.0365) between WT (19.11 μm) and Tg mice (11.13 μm). These findings suggest reduced vascular responsiveness may contribute to the systemic vascular deficits previously observed in AD models. Future research using diverse models and broader variables could further elucidate peripheral vascular dysfunction's role in AD pathogenesis, including its impact on motor symptoms and disease progression. Such insights may inform the development of vascular-targeted therapeutic strategies. [ABSTRACT FROM AUTHOR]

This study aimed to investigate the impact of a Western diet and resistance training on cardiac remodeling in a rat model of chemically induced mammary cancer. Fifty-six female Wistar rats were randomly assigned to one of eight experimental groups, evaluating the impact of Western and standard diets, exercise and sedentarism, and the induction of mammary cancer. Mammary cancer was induced via the intraperitoneal administration of N-methyl-N-nitrosourea (MNU) (50 mg/kg) at seven weeks of age. The resistance training protocol consisted of ladder climbing three times per week for an 18-week period, with a gradual increase in load over time. At the end of the 20-week experimental period, the animals were anesthetized and underwent echocardiography. Subsequently, the animals were euthanized, and organs and visceral adipose tissue (VAT) were collected and analyzed. A histopathological examination was performed on the mammary tumors. The Western diet increased relative VAT and contributed to cardiovascular and tumor-related changes, including an increase in interventricular septum thickness (IVS) and left ventricle posterior wall thickness (LVPW) at end-systole. Exercise reduced fat accumulation, improved cardiac performance, and helped regulate cardiovascular function, as indicated by a higher eccentricity index (EI) in the WD+EX group compared to the WD group. The WD was associated with increased VAT accumulation and initially delayed tumor initiation; however, over time, it contributed to bigger tumor aggressiveness. This diet also delayed tumor initiation but increased LVPW. Exercise, when combined with a WD, accelerated tumorigenesis, malignant transformation and invasiveness, resulted in the higher prevalence of invasive tumors. These findings underscore the complex and potentially compounding effects of diet and exercise on cancer progression. [ABSTRACT FROM AUTHOR]

Background/Objectives: Vitamin D (VD) plays a crucial role in age-related diseases, and its influence on cellular senescence (CS) could help clarify its function in aging. Considering VD's pleiotropic effects and the heterogeneity of CS. Methods: we utilized single-cell RNA sequencing (scRNA-seq) to explore these dynamics across multiple tissues. We analyzed three murine tissue datasets (bone, prostate, and skin) obtained from public repositories, enriching for senescence gene signatures. We then inferred gene regulatory networks (GRNs) at the tissue and cell-type levels and performed two cell communication analyses: one for senescent cells and another for interactions between senescent and non-senescent cells. Results: VD supplementation significantly decreased senescence scores in the skin (p = 3.96 × 10 − 134 ) and prostate ( p = 1.56 × 10 − 34 ). GRN analysis of the prostate revealed an altered macrophage–fibroblast regulatory relationship. In bone, distinct aging-related modules emerged for different bone lineages. In skin, contrary differentiation patterns between suprabasal and basal cells were observed. The main VD-modulated pathways were involved in inflammation, extracellular matrix remodeling, protein metabolism, and translation. VD reduced fibroblast–macrophage interactions in the prostate and skin but increased overall cellular crosstalk in bone. Conclusions: Our findings demonstrate that VD alleviates CS burden across tissues by modulating inflammation and metabolic processes and promoting differentiation. Key aging-related genes modulated by VD were linked to anabolism and cellular differentiation, suggesting VD's potential for therapeutic interventions targeting age-related diseases. [ABSTRACT FROM AUTHOR]

Background: In patients with chronic obstructive pulmonary disease (COPD), a sensitization to A. fumigatus has been related to a decline in lung function, but the role of fungal agents in the disease pathogenesis remains unclear. The main purpose of the present study was to investigate whether cell inflammation could worsen after exposure to A. fumigatus spores in vitro and then, in mice, following chronic exposure to cigarette smoke mimicking COPD. Methods: The inflammatory response to cigarette smoke alone or with A. fumigatus was investigated in cell culture models of murine macrophages and alveolar epithelial cells. In an animal model, mice were exposed daily to two cigarettes smoke over 14 weeks, and two intranasal instillations of 105 spores at weeks 7 and 14. Then, their lungs were recovered to perform inflammatory and histopathological analyses. Results: In co-cultures of macrophages and epithelial cells treated with both cigarette smoke extracts (CSE) and A. fumigatus compared to CSE alone there were significant inductions in TNF-α (6.2-fold) and CXCL-2 (21.5-fold) gene expression, confirmed by significant increases in the corresponding protein secretion. In the murine model, histological analyses of the lung after chronic smoke exposure showed an increase in airspace enlargement. Moreover, a Bio-Plex approach on bronchoalveolar lavage of cigarette smoke and A. fumigatus-treated mice showed significant increases in multiple inflammatory proteins secreted in the lung. Conclusions: There was a stronger inflammatory response after cigarette smoke exposure with A. fumigatus compared to cigarette smoke alone. These findings were correlated with histopathological changes in the mouse lung in vivo. [ABSTRACT FROM AUTHOR]

The efficacy of many compounds against Mycobacterium tuberculosis is often limited when administered via conventional oral or injection routes due to suboptimal pharmacokinetic characteristics. Inhalation-based delivery methods have been investigated to achieve high local therapeutic doses in the lungs. However, previous models, typically employing wild-type M. tuberculosis strains, were intricate, time-consuming, labor-intensive, and with poor reproducibility. In this study, we developed an autoluminescence-based inhalation administration model to evaluate drug activity by quantifying relative light units (RLUs) emitted from live mice infected with autoluminescent M. tuberculosis. This novel approach offers several advantages: (1) it eliminates the need for anesthesia in mice during administration and simplifies the instrument manipulation; (2) it is cost-effective by utilizing mice instead of larger animals; (3) it shortens the time from several months to 16 or 17 days for obtaining result; (4) it is non-invasive by directly measuring the live RLUs of mice as a surrogate marker for colony-forming units for in vivo drug activity testing; (5) up to six mice can be administrated daily and simultaneously, even 2–3 times/day; (6) results are relatively objective and reproducible results minimizing human factors. Proof-of-concept experiments demonstrated that inhalable rifampicin, isoniazid, and ethambutol showed anti- M. tuberculosis activity at concentrations as low as 0.5, 0.5, and 0.625 mg/mL, respectively, as evidenced by comparing the live RLUs of mice. Furthermore, consistency between RLUs and colony-forming units of the autoluminescent M. tuberculosis in lungs reaffirms the reliability of RLUs as an indicator of drug efficacy, highlighting the potential of this approach for accurately assessing anti- M. tuberculosis activity in vivo. This autoluminescence-based, non-invasive inhalation model offers a substantial reduction in the time, effort, and cost required for evaluating the efficacy of screening new drugs and repurposing old drugs in vivo via inhalation administration. [ABSTRACT FROM AUTHOR]

Mitochondria dysfunction plays a central role in the development of vascular diseases as oxidative stress promotes alterations in mitochondrial morphology and function that contribute to disease progression. Redox imbalances can affect normal cellular processes including mitochondrial biogenesis, electrochemical equilibrium, and the regulation of mitochondrial DNA. In this review, we will discuss these imbalances and, in particular, the potential role of mitochondrial fusion, fission, biogenesis, and mitophagy in the context of vascular diseases and how the dysregulation of normal function might contribute to disease progression. We will also discuss potential implications of targeting mitochondrial regulation as therapeutic targets to treat vascular disease formation. [ABSTRACT FROM AUTHOR]

Pseudomonas aeruginosa is a repertoire of several virulence factors that create a frightening high pathogenicity level as well as high antimicrobial resistance toward commercially used antibiotics. Therefore, finding a new alternative to traditional antimicrobials is a must. Resveratrol is a very famous phytochemical that harbors many beneficial health properties by possessing antibacterial, anti-inflammatory, and antioxidant properties. The current study aimed to explore the antimicrobial efficacy of resveratrol against P. aeruginosa and explore its ability to accelerate wound healing in a murine model. The obtained results revealed the potent antimicrobial, antivirulence, and wound-healing accelerating potentials of resveratrol against carbapenem-resistant P. aeruginosa (CRPA)-septic wounds. It significantly lowered the transcript levels of P. aeruginosa virulent genes toxA, pelA, and lasB. Additionally, resveratrol significantly accelerated skin wound healing by shortening the inflammatory phase and promoting re-vascularization, cell proliferation, re-epithelialization, and collagen deposition. Furthermore, it increased the immunoexpression of αSMA along with a reduction of the mRNA levels of VEGF, IL-1β, and TNF-α genes. Resveratrol has high therapeutic potential for the treatment of P. aeruginosa wound infection and is a prospective and promising candidate for this problem. [ABSTRACT FROM AUTHOR]

Abstract Background Prolonged therapy, hepatic damage, and the development of drug resistance are the limitations of doxycycline and rifampicin in the treatment of brucellosis. This study was designed to assess the effect of solid lipid nanoparticles (SLNs) encapsulation of these antimicrobials against brucella. SLNs were prepared by a double emulsion method and characterized for entrapment efficiency, particle size distribution, drug release, infrared spectroscopy, differential scanning calorimetry, and scanning electron microscopy. The encapsulated formulations were tested for stability, safety, and in vitro antimicrobial assay on brucella and brucella-infected mice models. Results The particle size, polydispersity index and zeta potential of doxycycline encapsulated SLN size were 443.6 ± 3.03 nm, 0.858 ± 0.00, and + 26.5 ± 1.87 mV, respectively. The rifampicin SLN showed particle size, polydispersity index, and zeta potential of 348.7 ± 3.35 nm, 0.234 ± 0.00, and + 22.9 ± 1.59 mV. The entrapment efficiency of doxycycline and rifampicin encapsulated SLN was 98% and 96%, respectively. The drug-loaded SLN retained the biophysical properties, drug loading, and entrapment efficiency after storage at 4 °C as well as 25 °C for 6 months. The Fourier transform infrared spectroscopy depicted effective encapsulation and the Differential scanning colorimetry thermogram revealed a negative interaction of drug and polymer. Drug release parameters were fitted well with the Korsmeyer–Peppas and Hixson–Crowell model (R2 ≥ .09). The MIC findings showed a reduction in MIC values of SLN-encapsulated rifampicin; whereas, doxycycline did not show any changes. The MBC value for free and SLN-encapsulated doxycycline and rifampicin did not show changes. SLN encapsulation did not show any cytotoxicity on murine macrophage cell line RAW 264.76 for both drugs. Doxycycline and rifampicin significantly reduced the CFU of B. abortus compared to the free drug (P > 0.05), resulting in less damage to the liver and kidneys. Conclusions The present study concludes that SLN encapsulation of doxycycline and rifampicin would be safe and effective for the prolonged treatment regimen against Brucella infection. Graphical abstract

Background: Prolonged therapy, hepatic damage, and the development of drug resistance are the limitations of doxycycline and rifampicin in the treatment of brucellosis. This study was designed to assess the effect of solid lipid nanoparticles (SLNs) encapsulation of these antimicrobials against brucella. SLNs were prepared by a double emulsion method and characterized for entrapment efficiency, particle size distribution, drug release, infrared spectroscopy, differential scanning calorimetry, and scanning electron microscopy. The encapsulated formulations were tested for stability, safety, and in vitro antimicrobial assay on brucella and brucella-infected mice models. Results: The particle size, polydispersity index and zeta potential of doxycycline encapsulated SLN size were 443.6 ± 3.03 nm, 0.858 ± 0.00, and + 26.5 ± 1.87 mV, respectively. The rifampicin SLN showed particle size, polydispersity index, and zeta potential of 348.7 ± 3.35 nm, 0.234 ± 0.00, and + 22.9 ± 1.59 mV. The entrapment efficiency of doxycycline and rifampicin encapsulated SLN was 98% and 96%, respectively. The drug-loaded SLN retained the biophysical properties, drug loading, and entrapment efficiency after storage at 4 °C as well as 25 °C for 6 months. The Fourier transform infrared spectroscopy depicted effective encapsulation and the Differential scanning colorimetry thermogram revealed a negative interaction of drug and polymer. Drug release parameters were fitted well with the Korsmeyer–Peppas and Hixson–Crowell model (R2 ≥.09). The MIC findings showed a reduction in MIC values of SLN-encapsulated rifampicin; whereas, doxycycline did not show any changes. The MBC value for free and SLN-encapsulated doxycycline and rifampicin did not show changes. SLN encapsulation did not show any cytotoxicity on murine macrophage cell line RAW 264.76 for both drugs. Doxycycline and rifampicin significantly reduced the CFU of B. abortus compared to the free drug (P > 0.05), resulting in less damage to the liver and kidneys. Conclusions: The present study concludes that SLN encapsulation of doxycycline and rifampicin would be safe and effective for the prolonged treatment regimen against Brucella infection. [ABSTRACT FROM AUTHOR]

Background: Cardiovascular diseases constitute one of the leading causes of morbidity and mortality worldwide. Herbal medicines represent viable alternatives to the synthetic drugs currently employed in the control of hypertension. This study aimed to isolate and identify the chemical markers of Kalanchoe crenata and to investigate the antihypertensive and anti-matrix metalloproteinase (MMP2) activities of an aqueous extract of the leaves. Methods: The main constituents of the aqueous extract of K. crenata were separated by ultra-performance liquid chromatography–mass spectrometry, and their presence was identified by NMR spectroscopy. Renovascular hypertension was induced in male Wistar rats using the two-kidney one-clip method (HTN groups), while control animals (Sham groups) were submitted to Sham surgery. Six groups of 10 animals each were treated daily for eight weeks as follows: Sham 1 (carrier), Sham 2 (K. crenata extract), HTN.1 (carrier), HTN.2 (K. crenata extract), HTN 3 (losartan), and HTN 4 (K. crenata extract with losartan). Results: The main compounds of the extract were patuletin 3-O-(4″-O-acetyl-α-L-rhamnopyranosyl)-7-O-(3‴-O-acetyl-α-L-rhamnopyranoside) (1), patuletin 3-O-α-L-rhamnopyranosyl-7-O-L-rhamnopyranoside (2), and trans-caffeoyl-malic acid (3), with compounds 1 and 2 being chemical markers of the species. Significant reductions (p < 0.05) in systolic blood pressure and MMP2 (72kDa isoform) activity were observed in the HTN 4 group. Conclusions: The association of K. crenata extract and losartan presented in vivo effects against hypertension. [ABSTRACT FROM AUTHOR]

Autism spectrum disorder (ASD) is a common neurodevelopmental condition mainly characterized by both a scarce aptitude for social interactions or communication and engagement in repetitive behaviors. These primary symptoms can manifest with variable severity and are often paired with a heterogeneous plethora of secondary complications, among which include anxiety, ADHD (attention deficit hyperactivity disorder), cognitive impairment, sleep disorders, sensory alterations, and gastrointestinal issues. So far, no treatment for the core symptoms of ASD has yielded satisfactory results in a clinical setting. Consequently, medical and psychological support for ASD patients has focused on improving quality of life and treating secondary complications. Despite no single cause being identified for the onset and development of ASD, many genetic mutations and risk factors, such as maternal age, fetal exposure to certain drugs, or infections have been linked to the disorder. In preclinical contexts, these correlations have acted as a valuable basis for the development of various murine models that have successfully mimicked ASD-like symptoms and complications. This review aims to summarize the findings of the extensive literature regarding the pharmacological and nutraceutical interventions that have been tested in the main animal models for ASD, and their effects on core symptoms and the anatomical, physiological, or molecular markers of the disorder. [ABSTRACT FROM AUTHOR]

Objectives: Diffuse alveolar hemorrhage (DAH) is a life-threatening complication of systemic lupus erythematosus and small vessel vasculitis. We previously showed that neutrophil extracellular traps (NETs) were associated with the pathogenesis of pristane-induced DAH and demonstrated that neutrophil NOD-like receptor family pyrin domain containing 3 (NLRP3) inflammasome assembly participated in NET generation under sterile stimulation. We investigated whether NLRP3 inflammasome assembly in neutrophils may drive pulmonary NETosis in a mouse model of pristane-induced DAH. Methods: C57BL/6J mice received a single intraperitoneal injection of 0.5mL of pristane. Neutrophil NLRP3 inflammasome assembly and NETs were characterized by immunofluorescence staining of apoptosis-associated speck-like protein a CARD (ASC), co-staining of DNA, and citrullinated histones, respectively. Clinical status of mice was assessed 11 days after pristane injection by measurement of arterial oxygen saturation and of weight loss; severity of lung injury was determined using a quantification score from hematoxylin-eosin-stained slides. Results: Pristane induced ASC speck formation in neutrophils and we confirmed that NLRP3 inflammasome was involved in NET generation after pristane stimulation in vitro. NLRP3 deficiency reduced the severity of pristane-induced DAH in female, but not male mice. Interestingly, NLRP3 deficiency reduced the number of neutrophils and NETs in the lungs of females compared to males. Conclusions: Our results suggest a link between female sex-specific NLRP3 inflammasome activation and subsequent pulmonary NETosis in the development of pristane-induced DAH. Therefore, we identified NLRP3 inflammasome as a potential new therapeutic target in this severe complication of pro-female autoimmune disease for which specific inhibitors of NLRP3 are currently developed. [ABSTRACT FROM AUTHOR]

Background: The pathological mechanism of the gastrointestinal forms of food allergies is less understood in comparison to other clinical phenotypes, such as asthma and anaphylaxis Importantly, high‐IgE levels are a poor prognostic factor in gastrointestinal allergies. Methods: This study investigated how high‐IgE levels influence the development of intestinal inflammation and the metabolome in allergic enteritis (AE), using IgE knock‐in (IgEki) mice expressing high levels of IgE. In addition, correlation of the altered metabolome with gut microbiome was analysed. Results: Ovalbumin‐sensitized and egg‐white diet‐fed (OVA/EW) BALB/c WT mice developed moderate AE, whereas OVA/EW IgEki mice induced more aggravated intestinal inflammation with enhanced eosinophil accumulation. Untargeted metabolomics detected the increased levels of N‐tau‐methylhistamine and 2,3‐butanediol, and reduced levels of butyric acid in faeces and/or sera of OVA/EW IgEki mice, which was accompanied with reduced Clostridium and increased Lactobacillus at the genus level. Non‐sensitized and egg‐white diet‐fed (NC/EW) WT mice did not exhibit any signs of AE, whereas NC/EW IgEki mice developed marginal degrees of AE. Compared to NC/EW WT mice, enhanced levels of lysophospholipids, sphinganine and sphingosine were detected in serum and faecal samples of NC/EW IgEki mice. In addition, several associations of altered metabolome with gut microbiome—for example Akkermansia with lysophosphatidylserine—were detected. Conclusions: Our results suggest that high‐IgE levels alter intestinal and systemic levels of endogenous and microbiota‐associated metabolites in experimental AE. This study contributes to deepening the knowledge of molecular mechanisms for the development of AE and provides clues to advance diagnostic and therapeutic strategies of allergic diseases. [ABSTRACT FROM AUTHOR]

Antiphospholipid syndrome (APS) is an autoimmune disease characterized by recurrent arteriovenous thrombosis and pathological pregnancy, accompanied by persistent antiphospholipid antibodies, (aPL). The incidence of APS is increasing year by year, clinicians lack of understanding of this type of disease, easy to misdiagnose and miss the diagnosis. Therefore, it is extremely important to establish a suitable animal model to reduce the process of disease development as much as possible and improve clinicians' understanding and understanding. This review will summarize the animal models of APS from the aspects of modeling methods, modeling mechanism, evaluation indicators and advantages and disadvantages of methods, providing a reference for finding an animal model highly similar to human APS, helping researchers to further clarify the pathogenesis of APS and find potential therapeutic targets, so as to achieve early diagnosis, early intervention, and ultimately improve the prognosis of patients. [ABSTRACT FROM AUTHOR]

Background: Chemical debridement is a fundamental step during the surgical treatment of both acute and chronic periprosthetic joint infection (PJI). However, there is no consensus on the optimal solution, nor is there sufficient evidence on the optimal irrigation time and combination of solutions. In an in vitro study, our group recently demonstrated that sequential combination debridement (SCD) with 3% acetic acid (AA) followed by 10% povidone iodine (PI) and 5 mM hydrogen peroxide (H2O2) was the best strategy for reducing bacterial load. The present study aimed to validate these findings in an in vivo model. Results: The median (IQR) log CFU/mL was lower in the group of mice treated with SCD (2.85 [0.00–3.72]) than in the Bactisure™ group (4.02 [3.41–4.72], p = 0.02). While this reduction was also greater than in the PI group (3.99 [1.11–4.33]), the difference did not reach statistical significance (p = 0.19). Cell viability assays showed no differences between treatments. S. aureus bacteremia was detected in 10% of mice treated with SCD, compared to 30% in the PI group and 10% in the Bactisure™ group. The difference was not statistically significant (p = 0.36). Conclusion: Our findings confirm that SCD significantly reduced bacterial load in an in vivo S. aureus PJI model, showing superior anti-biofilm activity compared to Bactisure™ and comparable performance to PI alone. These results highlight SCD's potential to serve as a standardized chemical debridement protocol, combining enhanced efficacy with clinical applicability. Methods: We tested SCD with 3% AA for 3 min, 10% PI for 3 min, and H2O2 for 3 min in a 7-day Staphylococcus aureus (ATCC29213)-based murine femur PJI model and compared the results with single treatments of 10% PI for 3 min or Bactisure™ solution for 3 min. A sterile steel implant with local administration of saline solution for 3 min was used as a non-infected control. After completing irrigation procedures, under anesthesia, mice were euthanized, and implants were analyzed for CFU/mL counts and cell viability rates. Blood cultures were obtained pre-euthanasia to detect bacteremia. [ABSTRACT FROM AUTHOR]

Diabetes mellitus type 2 (DM2) is the most common chronic disease worldwide, characterized mainly by increased glucose concentration in the blood and affecting several organs' functionality. The daily consumption of probiotic bacteria can help control diabetes and reduce the damage caused. Cell immobilization techniques are a powerful tool that provides physical cell protection to such probiotic bacteria against gastrointestinal conditions. We suggest that cell immobilization could be a significant vector for delivering a high quantity of viable probiotics to the gut, helping attenuate hyperglycemia in diabetic rats. Seventy male Wistar rats were used in this work. Nicotinamide was administrated via intraperitoneal injection 15 minutes before inducing type 2 diabetes (DM2), followed by a second intraperitoneal injection of streptozotocin to induce DM2. Rats were divided into seven groups. For 45 days, a specific treatment was applied to each group. The group of rats, supplied with immobilized Lactobacillus casei, showed a serum glucose concentration of 137 mg/dL, which was close to the one observed in the groups of healthy rats (117 mg/dL) and rats treated with metformin (155 mg/dL). The diabetic rats without treatment presented a higher serum glucose concentration (461 mg/dL). In the rats treated with immobilized L. casei, there was no biochemical parameter alteration, and the cell morphology of the analyzed tissues was similar to those of the healthy group. The consumption of immobilized L. casei could allow a high quantity of viable probiotics to be delivered to the gut, reducing serum glucose concentration by up to 70% compared to diabetic rats and reducing organ damage caused by diabetes. [ABSTRACT FROM AUTHOR]

Summary Multiple myeloma (MM), one of the most frequent haematological malignancies, significantly increases the risk of bacterial infections due to treatment‐related side effects, comorbidities and cancer‐induced immune deficiencies. Recently, CD71+ erythroid cells (CECs) have been identified as key immunomodulators in neonates and cancer patients, but their role in MM progression remains unclear. Using a murine MM model, closely resembling human disease, we observed that MM progression is associated with anaemia and an increase in immature CECs, which are characterized by elevated arginase 2 (ARG2) expression. These MM‐associated CECs suppress T‐cell proliferation, contributing to impaired immune responses. Notably, ARG2 deficiency in mice led to slower MM progression and improved survival. Furthermore, MM‐bearing mice exhibited higher susceptibility to Listeria monocytogenes infections, mirroring the increased infection risk in MM patients. Our findings suggest that ARG2‐expressing CECs play a critical role in MM‐associated immune suppression and infection susceptibility, pointing out ARG2 as a potential therapeutic target to enhance immune function and reduce infection risks in MM patients. [ABSTRACT FROM AUTHOR]

Wnt/β-catenin signaling is essential for adrenocortical development. Zinc and ring finger 3 (ZNRF3), an E3 ubiquitin ligase that attenuates Wnt/β-catenin signaling, is negatively regulated by R-spondin via an extracellular domain that is partially encoded by exon 2 of ZNRF3. We recently identified ZNRF3 exon 2 deletions in three individuals with congenital adrenal hypoplasia. ZNRF3 exon 2 deletion impairs R-spondin binding, thereby attenuating β-catenin expression and eventually leading to the development of congenital adrenal hypoplasia. To elucidate the influence of ZNRF3/Znrf3 exon 2 deletion on adrenocortical development, we generated homozygous Znrf3 exon 2 deletion (Znrf3Δ2/Δ2) mice. Whereas the adrenal glands of Znrf3Δ2/Δ2 mice did not show gross morphological changes at birth, moderate hyperplasia of the zona fasciculata (ZF), dispersed medulla arrangement, and a radially spreading zone with macrophage infiltration between the ZF and medulla were observed at 6 weeks of age. 20α-hydroxysteroid dehydrogenase, a marker of the adrenal X-zone, was hardly detected by immunostaining, and gene expression was significantly downregulated. The number of activated β-catenin-positive cells decreased in the zona glomerulosa, consistent with the results of in situ hybridization for Axin2, a Wnt/β-catenin target gene. Plasma ACTH and serum corticosterone levels in Znrf3Δ2/Δ2 mice did not differ significantly from those in wild-type mice. These results show a species-specific difference in the effects of ZNRF3/Znrf3 exon 2 deletions in humans and mice; Znrf3Δ2/Δ2 mice do not develop congenital adrenal hypoplasia but instead exhibit moderate ZF hyperplasia, dispersed medulla arrangement, X-zone dysplasia, and macrophage infiltration occurred in the inner cortex. [ABSTRACT FROM AUTHOR]

Background: Schistosomiasis affects approximately 250 million people worldwide, with 200,000 deaths annually. It has been documented that the granulomatous response to Schistosoma mansoni (S. mansoni) oviposition is the root cause of progressive liver fibrosis in chronic infection, in 20% of the patients, and can lead to liver cirrhosis and/or liver cancer. The influence of helminths coinfection on schistosomiasis-induced liver pathological alterations remains poorly understood. Therefore, in this study, we investigated the effect of Trichinella spiralis (T. spiralis) infection on S. mansoni-induced hepatic fibrosis. Materials and methods: Thirty adult male Balb-c mice were divided into three groups. Group 1 was left uninfected; group 2 was infected with S. mansoni cercariae and group 3 was orally infected with T. spiralis larvae, then 28 days later, this group was infected with S. mansoni cercariae. All groups were sacrificed at the end of the 8th week post infection with S. mansoni to evaluate the effect of pre-infection with T. spiralis on S. mansoni induced liver fibrosis was evaluated parasitologically (worm burden and egg count in tissues), biochemically (levels of alanine aminotransferase and aspartate aminotransferase), histopathologically (H&E and MT staining, and immunohistochemical staining for the expression of a-SMA, IL-6, IL-1b, IL-17, IL-23, TNF-a, and TGF-b). Results: The results in the present study demonstrated marked protective effect of T. spiralis against S. mansoni induced liver pathology. We demonstrated that pre-infection with T. spirais caused marked reduction in the number of S. mansoni adult worms (3.17 ± 0.98 vs. 18 ± 2.16, P = 0.114) and egg count in both the intestine (207.2 ± 64.3 vs. 8,619.43 ± 727.52, P = 0.009) and liver tissues (279 ± 87.2 vs. 7,916.86 ± 771.34; P = 0.014). Consistently, we found significant reductions in both number (3.4 ± 1.1 vs. 11.8.3 ± 1.22; P = 0.007) and size (84 ± 11 vs. 294.3 ± 16.22; P = 0.001) of the hepatic granulomas inmice pre-infected with T. spiralis larvae compared to those infected with only S. mansoni. Furthermore, pre-infection with T. spiralis markedly reduced S. mansoni-induced hepatic fibrosis, as evidenced by decreased collagen deposition, low expression of a-SMA, and significantly reduced levels of IL-17, IL-1B, IL-6, TGF-B, IL-23, and TNF-a compared to mice infected with S. mansoni only. Conclusions: Our data show that pre-infection with T. spiralis effectively protected mice from severe schistosomiasis and liver fibrosis. We believe that our findings support the potential utility of helminths for the preventing and ameliorating severe pathological alterations induced by schistosomiasis. [ABSTRACT FROM AUTHOR]

To minimize periprosthetic joint infection (PJI) risk, some clinicians prescribe extended antibiotic prophylaxis (EAP) following total joint arthroplasty (TJA). Given the limited evidence supporting EAP, we sought to evaluate impact of prophylactic antibiotic duration on PJI risk in a murine TJA model. A titanium prosthesis was implanted into the proximal tibia of 89 mice and inoculated with 102 colony forming units (cfu) of Staphylococcus aureus Xen36. Control mice (n = 20) did not receive antibiotics. Treated mice received either 24 h (n = 35) or 4 days (n = 34) of cefazolin prophylaxis. Cultures were obtained from the prostheses, tibia, femur, and knee tissues 3 weeks after surgery. All mice in the control group developed PJI. Both prophylaxis regimens reduced the rate of PJI relative to the control, with only 2/35 mice in the 24‐h cohort (p < 0.0001) and 1/34 in 4‐day cohort developing PJI (p < 0.0001). CFU counts from the prostheses, bone and knee tissues were reduced for the 24‐h and 4‐day prophylaxis cohorts relative to the control (p < 0.0001 for both). There was no difference in rates of PJI or CFU counts between the two prophylaxis cohorts (p = 0.58). Prophylactic cefazolin profoundly reduced rates of PJI in a murine model of TJA in which all control animals developed PJI. Extending cefazolin prophylaxis duration from 24 h to 4 days did not result in improved PJI rates or decreased bacterial loads in infected cases. While these results strongly support use of antibiotic prophylaxis for TJA, EAP did not appear to add benefit in the described mouse model. [ABSTRACT FROM AUTHOR]

Purpose: Murine models of pancreatic cancer with damp-heat syndrome were established based on two methods to explore the differences in the composition of intestinal flora and to seek characteristic genera with potential for model evaluation. Methods: In our study, thirty-four C57BL/6J male mice were randomly divided into a control group (Con), a model group (Mod), a classic damp-heat syndrome group (CDHS), and a climate-chamber group (CC). CDHS and CC groups were fed with a high-fat diet and glucose water, while the CDHS group was given 2.4 g/kg alcohol by gavage for 10 days, and the CC group was placed in a climatic chamber with a set temperature of (32 ± 1) °C and humidity of (92 ± 2)% for 10 days. The Mod group, CDHS group, and CC group underwent tumor-building experiments on day 11. Tumorigenicity was then assessed twice a week. After 4 weeks, feces, colon tissue, and tumor tissue were taken from the mice and were tested, and the mice were euthanized afterwards. Results: Mice in the CDHS and CC groups showed symptoms similar to the clinical damp-heat syndrome observed in traditional Chinese medicine (TCM), and exhibited a worse general condition and more rapid tumor growth trend than those in the Mod group. The pathological examination indicated that inflammation was prevalent in the CDHS and CC groups. Both groups had a disrupted intestinal barrier and an overgrowth of pathogenic bacteria such as c_Gammaproteobacteria, o_Enterobacteriales, and g_Bacteroides. Their microbiota composition showed greater diversity. Conclusions: Intestinal flora may have a promising future in the discovery of indicators for evaluating a model of damp-heat syndrome in pancreatic cancer. [ABSTRACT FROM AUTHOR]

Alzheimer’s disease (AD) is a complex neurocognitive disorder. Early theories of AD sought to identify a single unifying explanation underlying AD pathogenesis; however, evolving evidence suggests it is a multifactorial, systemic disease, involving multiple systems. Of note, vascular dysfunction, encompassing both cerebral and peripheral circulation, has been implicated in AD pathogenesis. This pilot study used intravital microscopy to assess differences in responsiveness of gluteal muscle arterioles between a transgenic AD mouse model (APP/PS1; Tg) and wild-type (C57BL/6; WT) mice to further elucidate the role of vascular dysfunction in AD. Arteriole diameters were measured in response to acetylcholine (10–9 to 10–5 M), phenylephrine (10–9 to 10–5 M), histamine (10–9 to 10–4 M) and compound 48/80 (10–9 to 10–3 M). Tg mice demonstrated a trend toward reduced vasodilatory response to acetylcholine with a significant difference at 10–5 M (36.91 vs. 69.55%: p = 0.0107) when compared to WT. No significant differences were observed with histamine, compound 48/80 or phenylephrine; however, a trend toward reduced vasoconstriction to phenylephrine was observed in Tg mice at higher concentrations. Mean net diameter change (resting to maximum) also differed significantly (p = 0.0365) between WT (19.11 μm) and Tg mice (11.13 μm). These findings suggest reduced vascular responsiveness may contribute to the systemic vascular deficits previously observed in AD models. Future research using diverse models and broader variables could further elucidate peripheral vascular dysfunction’s role in AD pathogenesis, including its impact on motor symptoms and disease progression. Such insights may inform the development of vascular-targeted therapeutic strategies.

The efficacy of many compounds against Mycobacterium tuberculosis is often limited when administered via conventional oral or injection routes due to suboptimal pharmacokinetic characteristics. Inhalation-based delivery methods have been investigated to achieve high local therapeutic doses in the lungs. However, previous models, typically employing wild-type M. tuberculosis strains, were intricate, time-consuming, labor-intensive, and with poor reproducibility. In this study, we developed an autoluminescence-based inhalation administration model to evaluate drug activity by quantifying relative light units (RLUs) emitted from live mice infected with autoluminescent M. tuberculosis. This novel approach offers several advantages: (1) it eliminates the need for anesthesia in mice during administration and simplifies the instrument manipulation; (2) it is cost-effective by utilizing mice instead of larger animals; (3) it shortens the time from several months to 16 or 17 days for obtaining result; (4) it is non-invasive by directly measuring the live RLUs of mice as a surrogate marker for colony-forming units for in vivo drug activity testing; (5) up to six mice can be administrated daily and simultaneously, even 2–3 times/day; (6) results are relatively objective and reproducible results minimizing human factors. Proof-of-concept experiments demonstrated that inhalable rifampicin, isoniazid, and ethambutol showed anti-M. tuberculosis activity at concentrations as low as 0.5, 0.5, and 0.625 mg/mL, respectively, as evidenced by comparing the live RLUs of mice. Furthermore, consistency between RLUs and colony-forming units of the autoluminescent M. tuberculosis in lungs reaffirms the reliability of RLUs as an indicator of drug efficacy, highlighting the potential of this approach for accurately assessing anti-M. tuberculosis activity in vivo. This autoluminescence-based, non-invasive inhalation model offers a substantial reduction in the time, effort, and cost required for evaluating the efficacy of screening new drugs and repurposing old drugs in vivo via inhalation administration.

Ovarian cancer, a leading cause of cancer-related deaths among women, has been notoriously difficult to screen for and diagnose early, as early detection significantly improves survival. Researchers and clinicians seek routinely usable and noninvasive screening methods; however, available methods (i.e., biomarker screening) lack desirable sensitivity/specificity. The most fatal form, high-grade serous ovarian cancer, often originate in the fallopian tube; therefore, sampling from the vaginal environment provides more proximal sources for tumor detection. To address these shortcomings and leverage proximal sampling, we developed an untargeted mass spectrometry microprotein profiling method and identified cystatin A, which was validated in an animal model. To overcome the limits of detection inherent to mass spectrometry, we demonstrated that cystatin A is present at 100 pM concentrations using a label-free microtoroid resonator and translated our workflow to patient-derived clinical samples, highlighting the potential utility of early stage detection where biomarker levels would be low.

Abstract Acute respiratory distress syndrome is a severe lung condition resulting from various causes, with life-threatening consequences that necessitate intensive care. The phenomenon can be modeled in preclinical models, notably through the use of lipopolysaccharide (LPS) instillation in mice. The phenotype induced closely recapitulates the human syndrome, including pulmonary edema, leukocyte infiltration, acute inflammation, impaired pulmonary function, and histological damage. However, the experimental designs using LPS instillations are extremely diverse in the literature. This highly complicates the interpretation of the induced phenotype chronology for future study design and hinders the proper identification of the optimal time frame to assess different readouts. Therefore, the definition of the treatment window in relation to the beginning of the disease onset also presents a significant challenge to address questions or test compound efficacy. In this context, the temporality of the different readouts usually measured in the model was evaluated in both normal and neutrophil-depleted male C57bl/6 mice using LPS-induction to assess the best window for proper readout evaluation with an optimal dynamic response range. Ventilation parameters were evaluated by whole-body plethysmography and neutrophil recruitment were evaluated in bronchoalveolar lavage fluids and in lung tissues directly. Imaging evaluation of myeloperoxidase along with activity in lung lysates and fluids were compared, along with inflammatory cytokines and lung extravasation by enzyme-linked immunoassays. Moreover, dexamethasone, the gold standard positive control in this model, was also administered at different times before and after phenotype induction to assess how kinetics affected each parameter. Overall, our data demonstrate that each readout evaluated in this study has a singular kinetic and highlights the key importance of the timing between ARDS phenotype and treatment administration and/or analysis. These findings also strongly suggest that analyzes, both in-life and post-mortem should be conducted at multiple time points to properly capture the dynamic phenotype of the LPS-ARDS model and response to treatment.

Antimicrobial peptides (AMPs) are regarded as a promising alternative to traditional antibiotics in the face of ever-increasing resistance. However, many AMPs fail to progress into clinics due to unexpected difficulties found in preclinical in vivo phases. Our research has focused on crotalicidin (Ctn), an AMP from snake venom, and a fragment thereof, Ctn[15-34], with improved in vitro antimicrobial and anticancer activities and remarkable serum stability. As the retroenantio versions of both AMPs maintained favorable profiles, in this work, we evaluate the in vivo efficacy of both the native-sequence AMPs and their retroenantio counterparts in a murine infection model with Acinetobacter baumannii. A significant reduction in bacterial levels is found in the mice treated with Ctn[15-34]. However, contrary to expectations, the retroenantio analogs either exhibit toxicity or lack efficacy when administered to mice. Our findings underscore the critical importance of in vivo infection model evaluation to fully calibrate the therapeutic potential of AMPs. [ABSTRACT FROM AUTHOR]

Primary ciliary dyskinesia (PCD) is an autosomal recessive genetic disorder characterized by ultrastructural defects in the cilia or flagella of cells, causing respiratory abnormalities, sinusitis, visceral transposition, and male infertility. DNAAF3 plays an important role in the assembly and transportation of axonemal dynein complexes in cilia or flagella and has been shown to be associated with PCD. To date, only two cases of PCD with infertility associated with DNAAF3 mutations have been reported, and no mouse models for this gene have been successfully constructed. This study was conducted on an infertile Chinese male patient with a history of bronchitis. Examination of the patient's semen revealed severe asthenozoospermia and teratospermia. Whole exome sequencing revealed a new homozygous loss‐of‐function DNAAF3 mutation. CRISPR‐Cas9 gene‐editing technology was used to construct the same mutation in C57/B6 mice, revealing that homozygous C57/B6 mice were characterized by severe hydrocephalus and early death. The results of this study expand the mutation spectrum of DNAAF3 and confirm its correlation with PCD pathogenesis. This study provides new insights on the mechanisms underlying male infertility related to DNAAF3 mutation and PCD. [ABSTRACT FROM AUTHOR]

Objectives: In this study, we establish a protocol for evaluating the outcomes of endothelial keratoplasty, including graft survival, rejection, or failure. Additionally, we also evaluate the alloimmune response in graft recipients. Methods: We performed EK using C57BL/6 (allogeneic) and BALB/c (syngeneic) as donors and BALB/c mice as recipients. Slit-lamp examination and optical coherence tomography were performed for clinical evaluations for 16 weeks post-procedure. Criteria for the assessment of corneal opacity were established and the animals were graded weekly. Additionally, we assessed corneal endothelial cell density by harvesting the corneas and staining with zonula occludens-1 (ZO-1). Lastly, lymph nodes were collected, and CD4+ T cells were MACS-sorted and co-cultured with syngeneic or allogeneic antigen-presenting cells (APCs) to assess the IFN-γ expression levels by alloreactive Th1 cells (ELISPOT) in response to the direct (donor) or indirect (host) pathways of sensitization. Results: We observed graft failure in four animals, including irreversible corneal opacity, graft detachment, and anterior synechiae in the first four weeks. The remaining animals were graded between 0 and 5 as per the established criteria. The total and graft corneal thickness and endothelial cell density progressively worsened with a higher grade of corneal opacity. The direct allosensitization of Th1 cells was significantly higher in mice with a higher grade of corneal opacity. At 16 weeks follow-up, the grafts remained stable with low opacity scores in syngeneic EK recipients; however, the opacity scores were higher and variable in allogeneic EK recipients. Conclusions: These findings establish a standardized protocol to assess the graft outcomes in a murine model of EK. Furthermore, we delineate the underlying immunological pathway that contributes to the immune-mediated rejection of grafts in this model. [ABSTRACT FROM AUTHOR]

Cardiovascular manifestations of coronavirus disease 2019 (COVID-19) include myocardial injury, heart failure, and myocarditis and are associated with long-term disability and mortality. Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) RNA and antigens are found in the myocardium of COVID-19 patients, and human cardiomyocytes are susceptible to infection in cell or organoid cultures. While these observations raise the possibility that cardiomyocyte infection may contribute to the cardiac sequelae of COVID-19, a causal relationship between cardiomyocyte infection and myocardial dysfunction and pathology has not been established. Here, we generated a mouse model of cardiomyocyte-restricted infection by selectively expressing human angiotensin-converting enzyme 2 (hACE2), the SARS-CoV-2 receptor, in cardiomyocytes. Inoculation of Myh6-Cre Rosa26loxP-STOP-loxP-hACE2 mice with an ancestral, non-mouse-adapted strain of SARS-CoV-2 resulted in viral replication within the heart, accumulation of macrophages, and moderate left ventricular (LV) systolic dysfunction. Cardiac pathology in this model was transient and resolved with viral clearance. Blockade of monocyte trafficking reduced macrophage accumulation, suppressed the development of LV systolic dysfunction, and promoted viral clearance in the heart. These findings establish a mouse model of SARS-CoV-2 cardiomyocyte infection that recapitulates features of cardiac dysfunctions of COVID-19 and suggests that both viral replication and resultant innate immune responses contribute to cardiac pathology. IMPORTANCE Heart involvement after severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection occurs in multiple ways and is associated with worse outcomes in coronavirus disease 2019 (COVID-19) patients. It remains unclear if cardiac disease is driven by primary infection of the heart or immune response to the virus. SARS-CoV-2 is capable of entering contractile cells of the heart in a culture dish. However, it remains unclear how such infection affects the function of the heart in the body. Here, we designed a mouse in which only heart muscle cells can be infected with a SARS-CoV-2 strain to study cardiac infection in isolation from other organ systems. In our model, infected mice show viral infection, worse function, and accumulation of immune cells in the heart. A subset of immune cells facilitates such worsening heart function. As this model shows features similar to those observed in patients, it may be useful for understanding the heart disease that occurs as a part of COVID-19. [ABSTRACT FROM AUTHOR]

Objectives: Rezafungin is the first new drug approved to treat candidaemia and invasive candidiasis in more than 10 years. However, data are scant on the in vivo efficacy of rezafungin and the other three approved echinocandins against different Candida auris clades. Methods: This study involved 10 isolates representing 4 C. auris clades: South Asian (n = 2), East Asian (n = 2), South African (n = 2), and South American (n = 4, including 2 environmental isolates). In the lethality experiment and fungal tissue burden experiment (kidney, heart, and brain), cyclophosphamide-treated BALB/c male mice were intravenously infected (107 and 8 × 106 colony-forming units [CFU]/mouse, respectively). A 20 mg/kg dose of rezafungin was administered on days 1, 3, and 6. Alternatively, beginning 24 h post-infection, mice received 3 mg/kg of caspofungin, 5 mg/kg of micafungin, or 5 mg/kg of anidulafungin once daily for 6 days. Results: Regardless of isolate and clade, all echinocandin regimens improved survival after 21 days (p = 0.0041 to p < 0.0001). All echinocandins frequently produced >3-log mean CFU/g decreases in the fungal kidney and heart burdens, although some of these decreases were not statistically significant. Rezafungin, regardless of clade, produced 3–5 and 2–4 log CFU/g decreases in the kidney and heart burdens, respectively. Echinocandins did not inhibit fungal growth in the brain. Histopathological examination performed on day 7 showed no fungal cells in the heart and kidneys of rezafungin-treated mice and to a lesser extent, caspofungin-treated mice, regardless of the clinical isolate. All echinocandin-treated mice showed medium and/or large foci of fungal cells in their cerebrum or cerebellum. Conclusions: Regardless of the C. auris clade, rezafungin activity in vivo was comparable to or improved over that of the three previously approved echinocandins. [ABSTRACT FROM AUTHOR]

Maternal obesity during pregnancy is associated with adverse pregnancy outcomes. This might be due to undesired obesity-induced changes in the maternal gut microbiota and related changes in the maternal immune adaptations during pregnancy. The current study examines how obesity affects gut microbiota and immunity in pregnant obese and lean mice during mid-pregnancy (gestational day 12 (GD12)). C57BL/6 mice were fed a high-fat diet or low-fat diet from 8 weeks before mating and during pregnancy. At GD12, we analyzed the gut microbiota composition in the feces and immune responses in the intestine (Peyer's patches, mesenteric lymph nodes) and the peripheral circulation (spleen and peripheral blood). Maternal obesity reduced beneficial bacteria (e.g., Bifidobacterium and Akkermansia) and changed intestinal and peripheral immune responses (e.g., dendritic cells, Th1/Th2/Th17/Treg axis, monocytes). Numerous correlations were found between obesity-associated bacterial genera and intestinal/peripheral immune anomalies. This study shows that maternal obesity impacts the abundance of specific bacterial gut genera as compared to lean mice and deranges maternal intestinal immune responses that subsequently change peripheral maternal immune responses in mid-pregnancy. Our findings underscore the opportunities for early intervention strategies targeting maternal obesity, ideally starting in the periconceptional period, to mitigate these obesity-related pregnancy effects. [ABSTRACT FROM AUTHOR]

Powassan virus (POWV) is an emergent tick-borne flavivirus that causes fatal encephalitis in the elderly and long-term neurologic sequelae in survivors. How age contributes to severe POWV encephalitis remains an enigma, and no animal models have assessed age-dependent POWV neuropathology. Inoculating C57BL/6 mice with a POWV strain (LI9) currently circulating in Ixodes ticks resulted in age-dependent POWV lethality 10–20 dpi. POWV infection of 50-week-old mice was 82% fatal with lethality sequentially reduced by age to 7.1% in 10-week-old mice. POWV LI9 was neuroinvasive in mice of all ages, causing acute spongiform CNS pathology and reactive gliosis 5–15 dpi that persisted in survivors 30 dpi. High CNS viral loads were found in all mice 10 dpi. However, by 15 dpi, viral loads decreased by 2–4 logs in 10- to 40-week-old mice, while remaining at high levels in 50-week-old mice. Age-dependent differences in CNS viral loads 15 dpi occurred concomitantly with striking changes in CNS cytokine responses. In the CNS of 50-week-old mice, POWV induced Th1-type cytokines (IFNγ, IL-2, IL-12, IL-4, TNFα, IL-6), suggesting a neurodegenerative pro-inflammatory M1 microglial program. By contrast, in 10-week-old mice, POWV-induced Th2-type cytokines (IL-10, TGFβ, IL-4) were consistent with a neuroprotective M2 microglial phenotype. These findings correlate age-dependent CNS cytokine responses and viral loads with POWV lethality and suggest potential neuroinflammatory therapeutic targets. Our results establish the age-dependent lethality of POWV in a murine model that mirrors human POWV severity and long-term CNS pathology in the elderly. IMPORTANCE Powassan virus is an emerging tick-borne flavivirus causing lethal encephalitis in aged individuals. We reveal an age-dependent POWV murine model that mirrors human POWV encephalitis and long-term CNS damage in the elderly. We found that POWV is neuroinvasive and directs reactive gliosis in all age mice, but at acute stages selectively induces pro-inflammatory Th1 cytokine responses in 50-week-old mice and neuroprotective Th2 cytokine responses in 10-week-old mice. Our findings associate CNS viral loads and divergent cytokine responses with age-dependent POWV lethality and survival outcomes. Responses of young mice suggest potential therapeutic targets and approaches for preventing severe POWV encephalitis that may be broadly applicable to other neurodegenerative diseases. Our age-dependent murine POWV model permits analysis of vaccines that prevent POWV lethality, and therapeutics that resolve severe POWV encephalitis. [ABSTRACT FROM AUTHOR]

Dental implants are increasing in prevalence as desirable options for replacing missing teeth. Unfortunately, implants come with complications, and animal models are crucial to studying the pathophysiology of complications. Current murine model experiments can be lengthy, with 8 weeks of extraction socket healing before implant placement. Therefore, we aimed to investigate the efficacy of decreasing extraction healing time from 8 to 4 weeks in a dental implant mouse model. Thirty-one 3-week-old C57BL/6J male mice underwent maxillary first and second molar extractions followed by 8 (control) or 4 (test) weeks of extraction socket healing before implant placement. Mice were euthanized after 4 weeks of implant osseointegration. Samples were analyzed via microcomputerized tomography and histology. When mice received implants 4 weeks after extractions, there was no statistical difference in initial bone crest remodeling or surrounding bone volume compared to those after 8 weeks of healing. Histologically, the hard and soft tissues surrounding both groups of implants displayed similar alveolar bone levels, inflammatory infiltrate, osteoclast count, and collagen organization. A 4-week extraction healing period can be utilized without concern for osseointegration in a murine implant model and is a viable experimental alternative to the previous eight weeks of healing. While small animal implant models are less directly applicable to humans, advancements in experimental methods will ultimately benefit patients receiving dental implants through improved prevention and treatment of complications. Subsequent research could investigate occlusal effects or whether healing time affects prognosis after induction of peri-implantitis. [ABSTRACT FROM AUTHOR]

Background: Animal models that use open surgical transection of the anterior cruciate ligament (ACL) do not accurately simulate the clinical condition regarding the pivot-shift mechanism and the associated inflammatory response that occurs before reconstruction. Purpose/Hypothesis: The purpose was to characterize a reproducible manual, nonsurgical method to mimic an isolated ACL tear in a clinically relevant model and to evaluate the development of progressive posttraumatic osteoarthritis due to ACL injury. It was hypothesized that the ACL could be reproducibly torn with minimal damage to other ligaments and that there would be progressive development of degenerative joint disease after ACL injury. Study Design: Controlled laboratory study. Methods: A total of 37 mice (strain C57BL/6) were used to compare the manual procedure with sham surgery (sham group; n = 10) and with the established surgical ACL transection (ACLT) procedure (surgical group; n = 27). In the sham group, a closed manual procedure was performed on the right knee and sham surgery on the left knee. In the surgical group, the closed manual procedure was performed on the right knee and surgical ACLT on the left knee. Dissection using India ink, histological assessment with safranin O and hematoxylin-eosin staining, radiological evaluation through radiographs and microfocus computed tomography scans, and gait analyses were performed to assess cartilage/ligament status. Osteoarthritis Research Society International (OARSI) and synovitis scores, anterior tibial translation, range of motion, bone microstructure, osteophyte volume, and pain were assessed at 2, 4, and 8 weeks postoperatively. Results: The manual procedure successfully resulted in an ACL rupture and associated meniscal injury. The posterior cruciate, lateral collateral, and medial collateral ligaments were intact in all dissected knees. Two weeks after ACL tear, the surgical group showed a significantly higher synovitis score, whereas 8 weeks after ACL tear, the manual group showed a significantly higher volume of osteophytes. No significant differences were found between the groups in terms of OARSI score, anterior tibial translation, range of motion, bone microstructure computed tomography values, and stride distance/irregularity. Conclusion: This procedure can be used to create an ACL tear model without causing grossly evident injuries to other ligaments and avoiding the risk of cartilage damage from surgical instruments. Clinical Relevance: This procedure offers a more clinically relevant ACL tear model and facilitates simple, inexpensive, and reproducible development of posttraumatic osteoarthritis. [ABSTRACT FROM AUTHOR]

The expression of nicotinic acetylcholine receptor (nAChR) subunits on various immune cells suggests their involvement in allergic rhinitis. However, how exactly they contribute to this pathogenesis is not yet confirmed. Our present study examined the therapeutic potential of GTS-21, an a7 nAChR agonist, for treating allergic rhinitis by employing its mouse models. GTS-21 treatment reduced allergen-induced immediate nasal response in ovalbumin (OVA)-sensitized model. However, nasal hyperresponsiveness or eosinophil infiltration elicited in either the OVAsensitized or T helper 2 cell-transplanted model was not affected by GTS-21. GTS-21 did not alter allergen-induced passive cutaneous anaphylaxis response in anti-dinitrophenyl IgE-sensitized mice. This evidence implies GTS-21's potential to alleviate allergic rhinitis without perturbing T cells or mast cells. [ABSTRACT FROM AUTHOR]

Idiopathic inflammatory myopathies (IIMs) are divided into polymyositis and dermatomyositis (DM) with specific cutaneous manifestation. Several myositis‐specific autoantibodies (MSAs) have been identified in IIMs and were found to be associated with distinct clinical features, including anti‐synthetase syndrome (ASyS) and immune‐mediated necrotizing myopathy (IMNM). Moreover, MSA‐related clinical features have been identified even within DM. Although MSAs are valuable for the diagnosis of IIMs, the pathogenic roles of these antibodies remain unknown. To investigate the pathogenesis of IIMs, classical murine models of autoimmune myositis, experimental autoimmune myositis, and C protein‐induced myositis have been established by immunization with muscle‐specific antigens, myosin, and myosin‐binding skeletal C protein, respectively. To according to MSA‐related autoimmunity, a murine model of ASyS was generated by immunization with a murine recombinant histidyl‐transfer RNA (tRNA) synthetase, Jo‐1, in which muscle and lung inflammation are induced depending on acquired immunity. Furthermore, it was found that the transfer of human Immunoglobulin G (IgGs) from patients with IMNM, comprising anti‐signal recognition particles and anti‐3‐hydroxy‐3‐methylglutaryl coenzyme A reductase antibodies, induced complement‐mediated myositis in recipient mice. We found that CD8+ T cell‐mediated myositis can be established depending on autoimmunity against transcriptional intermediary factor 1γ (TIF1γ), an autoantigen for MSAs induced by recombinant human TIF1γ immunization. These new murine models reflecting MSA‐associated IIMs will reveal the immunological mechanisms underlying IIMs. [ABSTRACT FROM AUTHOR]

High wall shear stress (HWSS) contributes to intracranial aneurysm (IA) development. However, the underlying molecular mechanisms remain unclear, in part due to the lack of robust animal models that develop IAs in a HWSS-dependent manner. The current study established a new experimental IA model in mice that was utilized to determine HWSS-triggered downstream mechanisms. By a strategic combination of HWSS and low dose elastase, IAs were induced with a high penetrance in hypertensive mice. In contrast, no IAs were observed in control groups where HWSS was absent, suggesting that our new IA model is HWSS-dependent. IA outcomes were assessed by neuroscores that correlate with IA rupture events. Pathological analyses confirmed these experimental IAs resemble those found in humans. Interestingly, HWSS alone promotes the turnover of collagen IV, a major basement membrane component underneath the endothelium, and the formation of endothelial podosomes, subcellular organelles that are known to degrade extracellular matrix proteins. These induced podosomes are functional as they degrade collagen-based substrates locally in the endothelium. These data suggest that this new murine model develops IAs in a HWSS-dependent manner and highlights the contribution of endothelial cells to the early phase of IA. With this model, podosome formation and function was identified as a novel endothelial phenotype triggered by HWSS, which provides new insight into IA pathogenesis.

ObjectivesDiffuse alveolar hemorrhage (DAH) is a life-threatening complication of systemic lupus erythematosus and small vessel vasculitis. We previously showed that neutrophil extracellular traps (NETs) were associated with the pathogenesis of pristane-induced DAH and demonstrated that neutrophil NOD-like receptor family pyrin domain containing 3 (NLRP3) inflammasome assembly participated in NET generation under sterile stimulation. We investigated whether NLRP3 inflammasome assembly in neutrophils may drive pulmonary NETosis in a mouse model of pristane-induced DAH.MethodsC57BL/6J mice received a single intraperitoneal injection of 0.5mL of pristane. Neutrophil NLRP3 inflammasome assembly and NETs were characterized by immunofluorescence staining of apoptosis-associated speck-like protein a CARD (ASC), co-staining of DNA, and citrullinated histones, respectively. Clinical status of mice was assessed 11 days after pristane injection by measurement of arterial oxygen saturation and of weight loss; severity of lung injury was determined using a quantification score from hematoxylin-eosin-stained slides.ResultsPristane induced ASC speck formation in neutrophils and we confirmed that NLRP3 inflammasome was involved in NET generation after pristane stimulation in vitro. NLRP3 deficiency reduced the severity of pristane-induced DAH in female, but not male mice. Interestingly, NLRP3 deficiency reduced the number of neutrophils and NETs in the lungs of females compared to males.ConclusionsOur results suggest a link between female sex-specific NLRP3 inflammasome activation and subsequent pulmonary NETosis in the development of pristane-induced DAH. Therefore, we identified NLRP3 inflammasome as a potential new therapeutic target in this severe complication of pro-female autoimmune disease for which specific inhibitors of NLRP3 are currently developed.

BackgroundSchistosomiasis affects approximately 250 million people worldwide, with 200,000 deaths annually. It has been documented that the granulomatous response to Schistosoma mansoni (S. mansoni) oviposition is the root cause of progressive liver fibrosis in chronic infection, in 20% of the patients, and can lead to liver cirrhosis and/or liver cancer. The influence of helminths coinfection on schistosomiasis-induced liver pathological alterations remains poorly understood. Therefore, in this study, we investigated the effect of Trichinella spiralis (T. spiralis) infection on S. mansoni-induced hepatic fibrosis.Materials and methodsThirty adult male Balb-c mice were divided into three groups. Group 1 was left uninfected; group 2 was infected with S. mansoni cercariae and group 3 was orally infected with T. spiralis larvae, then 28 days later, this group was infected with S. mansoni cercariae. All groups were sacrificed at the end of the 8th week post infection with S. mansoni to evaluate the effect of pre-infection with T. spiralis on S. mansoni induced liver fibrosis was evaluated parasitologically (worm burden and egg count in tissues), biochemically (levels of alanine aminotransferase and aspartate aminotransferase), histopathologically (H&E and MT staining, and immunohistochemical staining for the expression of α-SMA, IL-6, IL-1β, IL-17, IL-23, TNF-α, and TGF-β).ResultsThe results in the present study demonstrated marked protective effect of T. spiralis against S. mansoni induced liver pathology. We demonstrated that pre-infection with T. spirais caused marked reduction in the number of S. mansoni adult worms (3.17 ± 0.98 vs. 18 ± 2.16, P = 0.114) and egg count in both the intestine (207.2 ± 64.3 vs. 8,619.43 ± 727.52, P = 0.009) and liver tissues (279 ± 87.2 vs. 7,916.86 ± 771.34; P = 0.014). Consistently, we found significant reductions in both number (3.4 ± 1.1 vs. 11.8.3 ± 1.22; P = 0.007) and size (84 ± 11 vs. 294.3 ± 16.22; P = 0.001) of the hepatic granulomas in mice pre-infected with T. spiralis larvae compared to those infected with only S. mansoni. Furthermore, pre- infection with T. spiralis markedly reduced S. mansoni- induced hepatic fibrosis, as evidenced by decreased collagen deposition, low expression of α-SMA, and significantly reduced levels of IL-17, IL-1B, IL-6, TGF-B, IL-23, and TNF-α compared to mice infected with S. mansoni only.ConclusionsOur data show that pre-infection with T. spiralis effectively protected mice from severe schistosomiasis and liver fibrosis. We believe that our findings support the potential utility of helminths for the preventing and ameliorating severe pathological alterations induced by schistosomiasis.

Abstract Background Prenatal alcohol exposure (PAE) can result in lifelong disabilities known as foetal alcohol spectrum disorder (FASD) and is associated with childhood growth deficiencies and increased bone fracture risk. However, the effects of PAE on the adult skeleton remain unclear and any potential sexual dimorphism is undetermined. Therefore, we utilised a murine model to examine sex differences with PAE on in vitro bone formation, and in the juvenile and adult skeleton. Methods Pregnant C57BL/6J female mice received 5% ethanol in their drinking water during gestation. Primary calvarial osteoblasts were isolated from neonatal offspring and mineralised bone nodule formation and gene expression assessed. Skeletal phenotyping of 4- and 12-week-old male and female offspring was conducted by micro-computed tomography (µCT), 3-point bending, growth plate analyses, and histology. Results Osteoblasts from male and female PAE mice displayed reduced bone formation, compared to control (≤ 30%). Vegfa, Vegfb, Bmp6, Tgfbr1, Flt1 and Ahsg were downregulated in PAE male osteoblasts only, whilst Ahsg was upregulated in PAE females. In 12-week-old mice, µCT analysis revealed a sex and exposure interaction across several trabecular bone parameters. PAE was detrimental to the trabecular compartment in male mice compared to control, yet PAE females were unaffected. Both male and female mice had significant reductions in cortical parameters with PAE. Whilst male mice were negatively affected along the tibial length, females were only distally affected. Posterior cortical porosity was increased in PAE females only. Mechanical testing revealed PAE males had significantly reduced bone stiffness compared to controls; maximum load and yield were reduced in both sexes. PAE had no effect on total body weight or tibial bone length in either sex. However, total growth plate width in male PAE mice compared to control was reduced, whilst female PAE mice were unaffected. 4-week-old mice did not display the altered skeletal phenotype with PAE observed in 12-week-old animals. Conclusions Evidence herein suggests, for the first time, that PAE exerts divergent sex effects on the skeleton, possibly influenced by underlying sex-specific transcriptional mechanisms of osteoblasts. Establishing these sex differences will support future policies and clinical management of FASD.