Search Results (4,401)

Age-related decline in swallowing function is increasingly recognized as a clinical concern in aging populations. To better understand the biological mechanisms underlying functional and structural changes associated with normal aging, rodent models provide a controlled experimental platform. This review systematically examined age-related changes in swallowing function in healthy rodents, compared with that of young adults. A comprehensive literature search was conducted in PubMed, Embase, and the Cochrane Library. Twenty-nine articles were ultimately included in this review. Age-related alterations in swallowing function in healthy aged rodents were reported in the following categories: contraction properties of tongue muscles, histomorphological and biochemical changes in tongue muscles, swallowing-related cranial sensorimotor system, histological changes in pharyngeal muscles, and swallowing behavioral outcomes. The evidence summarized in this review provides insights into the functional, histological, and behavioral alterations in swallowing in healthy aged rodents compared with those of young adult rodents. These findings enhance the understanding of the biological basis of presbyphagia and support the translational value of rodent models in developing preventive and rehabilitative strategies for age-related dysphagia. Full article

Hurricanes cause severe impacts on lives, livelihoods, and essential systems. Hurricane Melissa impacted Jamaica as a Category 5 cyclone, resulting in estimated losses of approximately 41% of national GDP (US$8.8 billion) and eliciting widespread damage to housing, healthcare, agriculture, and urban infrastructure. Agriculture sustained heavy losses, with 41,000 hectares of damaged farmland and the loss of more than 1 million livestock animals. These impacts resulted in exposed animal closures with biological hazards. Using systems thinking, the PESTHEEL framework, and a One Health lens, we argue for viewing Hurricane Melissa as series of cascading inter-related One Health threats of waterborne and vector-borne diseases, zoonoses, antimicrobial resistance, degraded indoor and outdoor air quality, chemical pollution, and shifting migration and border dynamics. These each unfold at different timings. A structured synthesis for Jamaica and other Caribbean Small Island Developing States is provided by integrating systems thinking, One Health, and the PESTHEEL framework. Immediate and lagged risk pathways are identified, and practical risk reduction actions are proposed to support anticipatory, multisectoral recovery: enhanced syndromic, laboratory, wastewater, vector, and rodent surveillance; resilient WASH and shelter systems; non-insecticidal and integrated vector management; biosecure aid and border protocols; environmental toxicology monitoring; and climate–health intelligence. Full article

Traumatic injuries often result in nerve tissue damage and functional deficits due to limited regeneration. Silk fibroin, a biopolymer with inherent biocompatibility and tunable properties, is a promising material for 3D-bioprinted neural tissue scaffolds. This review highlights recent advancements in silk-derived composite scaffolds, often incorporating additional materials like collagen or conductive polymers to enhance their performance. This review examines how material composition, scaffold architecture, and fabrication strategy influence biological response and functional recovery. This comprehensive review follows PRISMA guidelines and uses comprehensive searches of PubMed, MEDLINE, Embase, Web of Science, Cochrane Central, and ClinicalTrials.gov for studies published through 2025. Studies were screened for eligibility based on substance type, mechanical properties, production methods, and outcomes. Findings were synthesized qualitatively. Twelve studies were included, comprising rat (50%), canine (8.3%), and in vitro (41.7%) models. Analysis reveals that silk fibroin acts as a highly adaptable mechanical backbone. It can consistently integrate with bioactive additives (collagen, dECM) or conductive polymers (Polypyrrole, MXene) to meet specific therapeutic demands. For spinal cord injuries, composites reached a compressive modulus capable of resisting physiological pressures and preventing scaffold collapse. In soft tissue applications, silk–hydrogel blends provided localized release of exosomes and small molecules during the acute injury phase, reducing neuroinflammatory markers. Additionally, adding conductive materials allowed the scaffolds to bridge electrical gaps and promote Schwann cell proliferation and neuronal differentiation. Furthermore, 3D bioprinting enabled the creation of defined microchannels that replicate native fascicular architecture. In vivo outcomes consistently showed superior axonal regeneration, myelination, and synaptic reconnection compared to controls, correlating with significant improvements in electrophysiological and motor function. This review highlights the clinical potential of silk fibroin-based 3D-printed biomaterials for nerve regeneration, including neural repair and neural tissue engineering. More recent studies place greater emphasis on integrating mechanical, architectural, and biological considerations into scaffold design, resulting in increasingly multifunctional scaffold systems. Despite promising efficacy, the heterogeneity of fabrication methods and the predominance of rodent models highlight the need for standardized protocols and evaluations in relevant models to facilitate clinical translation. Full article

Adult hippocampal neurogenesis persists throughout the human lifespan, yet declines in Alzheimer’s disease and major depression, associated in part with reduced brain-derived neurotrophic factor (BDNF) levels. For rodents, environmental enrichment, dichotomised primarily as physical activity and spatial complexity, robustly promotes adult hippocampal neurogenesis, but no framework has translated these findings to human environments. This review is the first to synthesise evidence across the full translational pathway, arguing that spatial complexity and physically active navigation in neighbourhoods and buildings constitute a humanised form of environmental enrichment. It proposes that standard indoor environments may represent a functionally impoverished condition for the human hippocampus, paralleling standard laboratory caging. An applied model is presented, mapping built environment features onto the neurobiological mechanisms regulating adult hippocampal neurogenesis, with BDNF as the central translatable biomarker linking environmental exposures to neurogenic outcomes. A methodological roadmap for future empirical validation is also outlined. This framework repositions the built environment as a modifiable determinant of adult hippocampal neurogenesis in humans, with implications for mitigating the risk of depression, cognitive impairment, and Alzheimer’s disease. Full article

Background/Objectives: Metabolic dysfunction-associated fatty liver disease (MAFLD), previously known as non-alcoholic fatty liver disease (NAFLD), is the most prevalent chronic liver disease worldwide, affecting approximately 25% of the global population. MAFLD represents a broad disease spectrum ranging from simple steatosis to metabolic dysfunction-associated steatohepatitis (MASH), fibrosis, cirrhosis, and hepatocellular carcinoma (HCC). The availability of experimental models that faithfully reproduce human metabolic and hepatic pathology is essential for elucidating disease mechanisms and advancing therapeutic development. This review aims to critically evaluate commonly used rodent models of MAFLD and provide guidance for model selection based on specific research objectives. Methods: A narrative, semi-systematic literature search was performed using PubMed Central, Ovid MEDLINE, and Google Scholar. Rodent models were classified according to their mode of disease induction, including diet-induced, genetically engineered, chemically or pharmacologically induced, and combination models. Models were assessed based on frequency of use, relevance to different stages of MAFLD progression, metabolic fidelity, and suitability for mechanistic studies and preclinical therapeutic evaluation. Results: Diet-induced models incorporating high fat, fructose, and cholesterol most closely recapitulate human metabolic dysfunction and are highly relevant for translational research and drug screening. Nutrient-deficient diets induce rapid steatohepatitis and fibrosis but lack key features of metabolic syndrome. Genetic models enable the targeted interrogation of specific metabolic and inflammatory pathways, whereas chemical and combination models accelerate fibrosis and HCC development. No single rodent model fully reproduces the entire spectrum of human MAFLD. Conclusions: Rodent models remain indispensable tools for MAFLD research; however, their applicability depends on alignment with the defined experimental goals. Careful selection of models based on disease stage, dominant pathogenic mechanisms, and translational intent is essential for improving reproducibility and clinical relevance. This review provides a practical framework to guide investigators in choosing appropriate preclinical models for mechanistic studies and therapeutic development in MAFLD. Full article

Cognitive impairment (CI) is prevalent among heart failure (HF) patients. Although the brain injury in HF is multifactorial, oxidative stress and neuroinflammation are common pathological features of neurological disorders and are increasingly recognized as key mechanisms underlying CI. Extracellular vesicles (EVs) are well-established mediators of biological signaling in myocardial function and are widely recognized for transporting a variety of microRNAs. However, whether myocardial injury alters the miRNA profiles of brain EVs, potentially contributing to cognitive impairment (CI) by disrupting brain homeostasis, remains poorly understood. Using a rodent myocardial infarction (MI) model, we isolated brain EVs and characterized their miRNA profiling by means of small RNA sequencing. Our results demonstrate that miRNA profiles in brain EVs vary with HF progression. Only three miRNAs were significantly changed at 3 weeks post-MI, whereas thirty-two miRNAs and sixty-five miRNAs demonstrated significant changes post-MI, showed significant alterations at 6 and 12 weeks post-MI, respectively. Bioinformatic analysis suggests that some miRNAs against oxidative stress and inflammation were downregulated in brain EVs at 6 and 12 weeks post-MI. Conversely, several miRNAs responsible for oxidative stress and neuroinflammation were significantly increased, which may be of cardiac origin following MI. Collectively, these findings suggest that cardiac EVs may contribute to miRNA alterations in brain EVs, potentially driving CI by disrupting brain homeostasis. Full article

Although hantaviruses have traditionally been considered geographically restricted rodent-borne pathogens, globalization, climate change, ecosystem disruption, and environmental contamination may collectively favor novel transmission scenarios and altered epidemiological patterns. The experience gained during the SARS-CoV-2 pandemic showed the importance of environmental determinants, airborne exposure, and host susceptibility factors in emerging viral diseases. In this context, increasing but still indirect evidence suggests that environmental toxicants and the exposome may modulate susceptibility to hantavirus infection and influence disease severity. The proposed mechanisms include oxidative stress, endothelial dysfunction, pulmonary inflammation, and immune dysregulation, rather than direct causal effects of toxicants on infection itself. This article discusses current knowledge regarding interactions among toxic environmental exposures, climate change, and hantavirus disease, with special emphasis on Andes orthohantavirus (ANDV), the principal hantavirus known to exhibit person-to-person transmission. The article integrates recent evidence within the One Health framework and highlights future research priorities linking environmental toxicology, zoonotic disease ecology, and global environmental change. Full article

Standard laboratory housing often restricts the expression of natural behaviors in rodents, raising concerns regarding animal welfare and the translational value of experimental data. The current study investigated whether increasing cage bedding volume functions as an effective, low-impact environmental enrichment strategy that enhances welfare without confounding physiological parameters. An in-depth analysis was conducted comparing the effect of Deep Bedding (DB; 1600 mL) versus Normal Bedding (NB; 400 mL) on the microenvironment, physiology, and behavior of wild-type (129SV) and desmin-knockout (Des−/−) mice. Results demonstrated that deep bedding acts as a significant environmental buffer, effectively decoupling intra-cage temperature and humidity from ambient room fluctuations. While physiological parameters, including body surface temperature, body weight, and food intake, remained stable across bedding conditions, behavioral analysis revealed a robust upregulation of species-specific fossorial activities, such as digging and burrowing, in the DB group. This suggests a beneficial “bioenergetic reallocation” where energy is directed toward natural behaviors rather than thermal stress responses. Furthermore, deep bedding significantly improved cage hygiene through the mechanical sequestration of waste. These findings indicate that deep bedding serves as a multifactorial refinement strategy that supports animal welfare and hygiene without increasing experimental variability, proving safe even for physiologically sensitive models like Des−/− mice. Full article

Background/Objectives: The Chinese porcupine (Hystrix hodgsoni) is a distinctive rodent species characterized by specialized ecological adaptations and sensory traits; however, genomic resources for this species have remained limited. This study aims to provide a reliable reference for comparative and evolutionary analyses by constructing a high-quality genome. Methods: We generated a chromosome-level genome assembly of the Chinese porcupine using long-read sequencing combined with chromatin conformation-based scaffolding, followed by comprehensive structural and functional annotation. Comparative genomic analyses across representative mammals and functional enrichment analyses were conducted to investigate lineage-specific gene family dynamics. Results: The assembled genome shows high contiguity and completeness. Comparative analyses revealed a substantial number of gene families significantly expanded along the porcupine lineage. Functional enrichment demonstrated strong overrepresentation of olfactory-related processes, including olfactory receptor activity, odorant binding, and detection of chemical stimuli. Additionally, several expanded families were associated with epidermal differentiation, keratinization, and skin development. Conclusions: Gene family expansions in the Chinese porcupine are biased toward sensory perception and epidermal functions, suggesting potential genetic bases for its enhanced environmental sensing and integumentary specialization. This assembly provides an important genomic resource for porcupine research and new insights into the molecular mechanisms underlying sensory and skin-related adaptations in rodents. Full article

Rodents and shrews are important reservoir hosts due to their close association with human activities and their role in carrying various zoonotic pathogens. Recently, meta-transcriptomic sequencing has become a powerful tool for surveilling and screening novel pathogens from wild animals. However, many of these studies focused only on the diversity and genetic evolution of viruses from wildlife, while ignoring non-viral pathogens such as bacterial and eukaryotic microorganisms. Here, we performed a comprehensive infectome analysis of 227 tissue samples collected from 42 rodents and 16 shrews across six cities of Guangdong Province, China. We identified 34 viral families, including 23 mammalian viruses. Phylogenetic analysis revealed a henipavirus from the kidneys of shrews closely related to the Langya virus with potential infection risks to humans. Additionally, two potential pathogenic bacteria and 12 eukaryotic pathogens from six genera were found, showing clearer organ tropism than viruses. Interestingly, a moderate positive abundance correlation between Usmuvirus newyorkense and Trichinella suggested a potential virus–parasite association. We used machine learning models to evaluate the zoonotic potential of the obtained viruses, which indicated that 15 of 23 viral species were high risk for human infection. These findings provide important insight into the substantial zoonotic threat posed by pathogens circulating in wild small mammals in southern China and highlight the necessity for persistent wildlife pathogen surveillance. Full article

The consumption of wild rodents in certain regions of Southwest China creates a potential interface for zoonotic pathogen exposure, yet the virome composition of edible rodents remains insufficiently characterized. In this study, we performed multi-organ RNA metatranscriptomic analysis of three commonly consumed rodent species (Niviventer andersoni, Berylmys bowersi, and Rattus losea) collected from Guizhou Province, analyzing five visceral organs per species. A total of 1198 viral contigs spanning 37 viral families were identified, revealing diverse viral communities across host species and tissues, with host identity emerging as a key factor shaping virome structure. Sequences related to Seoul virus were detected in the lungs of R. losea, showing high similarity to previously reported strains, and sequences closely related to porcine Rotavirus A were identified in the lung samples of N. andersoni, indicating a close phylogenetic relationship with livestock-associated viruses. While these findings do not confirm active infection or transmission, they may reflect potential environmental exposure or ecological links at the wildlife–livestock interface. Overall, this study provides a baseline characterization of the multi-organ virome of edible rodents and highlights the importance of integrated surveillance and risk assessment within a One Health framework. Full article

Oxytocin’s capacity to affect the glial cell functions is increasingly recognized. We previously reported that oxytocin could cause both excitation and inhibition of Ca²⁺ signals and glutamate release in the processes of adult rodent astrocytes. Our purpose here was to investigate oxytocin receptor expression and oxytocin effects in astrocytes. In primary cortical astrocytes, we assessed the presence of oxytocin receptors by confocal imaging, and the effects of oxytocin receptor activation on intracellular Ca²⁺ signals and glutamate release. We found that oxytocin receptors are expressed in both the soma and processes of astrocytes; oxytocin at nanomolar concentrations could induce dual responses in astrocytes, namely facilitation and inhibition of Ca²⁺ signals and glutamate release; the oxytocin facilitatory and inhibitory effects were duplicated by the biased agonists carbetocin and atosiban, respectively; and the facilitatory and the inhibitory effect were dependent on activation of a G_q and a G_i pathway, respectively. It is concluded that oxytocin effects in astrocytes could duplicate the effects in processes prepared from astrocytes matured in neuron-astrocyte networks, substantiating the use of astrocytes to study astrocytic oxytocin molecular signaling. Full article

The growing global protein demand and environmental concerns from conventional animal agriculture have driven the exploration of sustainable alternative protein sources. Single-cell proteins (SCPs) from microbial fermentation offer a promising solution. This study comprehensively evaluated the nutritional value and safety profile of SCP produced from Ralstonia eutropha H16 through integrated in vitro and in vivo assessments. Nutritional analyses revealed a high crude protein content of 71.87 ± 5.05 g/100 g dry weight, with total amino acids of 53.67 ± 1.05 g/100 g. The essential amino acid content was 24.38 ± 0.51 g/100 g, accounting for 45% of the total amino acids. An essential amino acid index (EAAI) of 1.46 ± 0.04 and an amino acid score (AAS) of 0.83 ± 0.06 confirmed its classification as a high-quality protein source according to FAO/WHO standards. In vivo rat feeding trials demonstrated an adjusted protein efficiency ratio (PER) of 1.81, exceeding common plant proteins such as wheat (0.8–1.1). True digestibility (TD) reached 85.73%, with a biological value (BV) of 49.37%, net protein utilization (NPU) of 42.33%, and protein digestibility-corrected amino acid score (PDCAAS) of 0.71. Comprehensive safety assessments included chemical contaminant screening, acute oral toxicity studies in rats and mice, in vitro chromosome aberration tests, and erythrocyte micronucleus tests. Heavy metals and aflatoxin B₁ levels were below regulatory limits. Acute oral toxicity studies established LD₅₀ values exceeding 10,000 mg/kg body weight in both rodent species, classifying this protein source as practically non-toxic. The 28-day sub-acute toxicity study showed no significant adverse effects at low doses (6.25% protein replacement). Both genotoxicity assays (mammalian cell chromosome aberration assay and mammalian erythrocyte micronucleus test) returned negative results. These findings establish R. eutropha H16-derived SCP as a safe, nutritious, and sustainable protein source with considerable potential for feed and food applications, contributing to global food security and environmental sustainability. Full article

Aluminum chloride (AlCl₃) is widely used in experimental toxicology, particularly in rodent models of neurodegeneration, where its effects have been studied primarily in the central nervous system. However, experimental findings also indicate that chronic exposure is associated with changes across multiple peripheral organs, although these observations are often considered separately. In this review, we bring together evidence from different organ systems to examine aluminum toxicity from a broader perspective. Rather than focusing on isolated tissue-specific effects, we consider the extent to which reported findings may reflect overlapping molecular disturbances expressed across physiological systems. Within this context, organ-level outcomes are discussed as potentially related manifestations of shared underlying processes, while acknowledging variability in experimental conditions and model interpretation. To structure this synthesis, we outline a conceptual framework that links recurring molecular responses, system-level regulatory influences, and tissue-specific patterns of injury. This approach is intended to provide a more integrated way of organizing existing data rather than to establish a single unifying mechanism. Importantly, the pathological alterations discussed throughout this review are interpreted as experimentally observed toxicological manifestations of chronic AlCl₃ exposure rather than evidence that aluminum constitutes a definitive etiological cause of Alzheimer’s disease. Overall, this review aims to complement existing neuro-focused interpretations of the AlCl₃ model by situating it within a multi-organ context and highlighting areas where further integrative investigation may be warranted. Full article

Bromalites (trace fossils produced by food processing) from the early Eocene Willwood Formation of Wyoming contain abundant glyptosaurid lizard skeletal elements. They clearly represent bromalites as they are discrete, three-dimensional, disarticulated accumulations of biological materials. Furthermore, they contain abundant skeletal elements, principally osteoderms, that exhibit no indication of digestion, so they can be identified as regurgitalites. The Willwood specimens represent orniothoregurgitalites, specifically strigilites, the regurgitalites of owls. These strigilites are assigned to Sauresus osteodermus igen. et isp. nov. This ichnotaxon is characterized by an elongate, sub-cylindrical or sub-ovoid bromalite pellet with irregular surface texture that is composed of a micritic matrix and contains abundant, well-preserved skeletal elements of glyptosaurids, principally osteoderms. The strigilites were probably produced by Primoptynx poliotauros that used its feet to kill glyptosaurids. The lizard, rather than rodent, content of the strigilite supports the hypothesis that Eocene owls were diurnal in habit and only became nocturnal in the Oligocene. Full article