Animal Models Of Disease Research Articles

3D Imaging of Striatal Transplants in a Small Animal Model of Huntington's Disease.

High-resolution imaging in small animal models of neurologic disease is a technical challenge. In a pilot project, we have explored a non-destructive synchrotron imaging technique for the 3D visualization of intracerebral tissue transplants in a well-established small animal model of Huntington's disease. Four adult female Sprague Dawley rats each received injections of 0.12 M quinolinic acid (QA) into two target positions in the left striatum, thus creating unilateral left-sided striatal lesions similar to those frequently seen in patients suffering from Huntington's disease. One week after lesioning, the animals received transplants prepared from whole ganglionic eminences (wGEs) obtained from 13- to 14-day-old rat embryos. Of the four lesioned animals, three received transplants of GNP-loaded cells and one animal received a transplant of naïve cells, serving as control. Post-mortem synchrotron-based microCT was used to obtain images of the neurotransplants. The images obtained of GNP-loaded tissue transplants at the synchrotron corresponded in size and shape to the histological images of transplants developed from naïve cells. Thus, we conclude that non-destructive synchrotron imaging techniques such as phase-contrast imaging are suitable to obtain high-resolution images of GNP-loaded tissue transplants.

The Use of Zebrafish and in Vivo PAL as a Novel Discovery Platform for Psychoactive Agents

Our research is utilizing the zebrafish model to study molecular processes and animal models of human diseases. These studies discussed here start to assess how different bath salts and methamphetaminecause death upon overdose by addressing the molecules that may bind to the illicit drugs. We have accomplished this by developing an in vivo photo-affinity labelling (PAL) system and studying the drugs in our system. The zebrafish has been lauded as a unique and powerful tool to examine development in a vertebrate animal and address molecular aspects of human disease for decades. We will examine recent published data from our laboratory utilizing the PAL system we developed.

Gla-domain mediated targeting of externalized phosphatidylserine for intracellular delivery.

Phosphatidylserine (PS) is a negatively charged phospholipid normally localized to the inner leaflet of the plasma membrane of cells but is externalized onto the cell surface during apoptosis as well as in malignant and infected cells. Consequently, PS may comprise an important molecular target in diagnostics, imaging, and targeted delivery of therapeutic agents. While an array of PS-binding molecules exist, their utility has been limited by their inability to internalize diagnostic or therapeutic payloads. We describe the generation, isolation, characterization, and utility of a PS-binding motif comprised of a carboxylated glutamic acid (GLA) residue domain that both recognizes and binds cell surface-exposed PS, and then unlike other PS-binding molecules is internalized into these cells. Internalization is independent of the traditional endosomal-lysosomal pathway, directly entering the cytosol of the target cell rapidly. We demonstrate that this PS recognition extends to stem cells and that GLA-domain-conjugated probes can be detected upon intravenous administration in animal models of infectious disease and cancer. GLA domain binding and internalization offer new opportunities for specifically targeting cells with surface-exposed PS for imaging and delivery of therapeutics.

Tick salivary gland components dampen Kasokero virus infection and shedding in its vertebrate reservoir, the Egyptian rousette bat (Rousettus aegyptiacus)

BackgroundThe human-pathogenic Kasokero virus (KASV) circulates in an enzootic transmission cycle between Egyptian rousette bats (ERBs; Rousettus aegyptiacus) and their argasid tick ectoparasites, Ornithodoros (Reticulinasus) faini. Although tick salivary gland components have been shown to potentiate virus infection in vertebrate non-reservoirs (i.e. incidental hosts or small animal models of disease), there is a lack of information on the effect of tick salivary gland components on viral infection and shedding in vertebrate reservoirs.MethodsTo determine the impact of tick salivary gland components on KASV infection and shedding in ERBs, KASV loads were quantified in blood, oral swab, rectal swab, and urine specimens collected daily through 18 days post inoculation from groups of ERBs intradermally inoculated with KASV or KASV + O. (R.) faini tick salivary gland extract (SGE).ResultsBats inoculated with KASV + tick SGE had significantly lower peak and cumulative KASV viremias and rectal shedding loads compared to bats inoculated with KASV only.ConclusionsWe report for the first time to our knowledge that tick salivary gland components dampen arbovirus infection and shedding in a vertebrate reservoir. This study advances our understanding of biological factors underlying arbovirus maintenance in nature.Graphical abstract

Vitamin K2 protects against aluminium chloride-mediated neurodegeneration.

Recent studies have shown that, coupled with other environmental factors, aluminium exposure may lead to neurodegeneration resulting in cognitive impairment resembling Alzheimer's disease. Menaquinone, a form of vitamin K2, aids in maintaining healthy bones and avoids coronary calcification. It also has anti-inflammatory and antioxidant properties. Here, we study the neuroprotective effects of vitamin K2 (MK-7) using the animal model of Alzheimer's disease (AD). Aluminium chloride (AlCl3; 100mg/kg for 3weeks orally) was administered to Swiss albino mice to induce neurodegeneration and Vitamin K2 (100g/kg for 3weeks orally) was applied as treatment. This was followed by behavioural studies to determine memory changes. The behavioural observations correlated with proinflammatory, oxidative, and brain histopathological changes in AlCl3-treated animals with or without vitamin K2 treatment. AlCl3 administration led to memory decline which was partially restored in Vitamin K2 treated animals. Myeloperoxidase levels in the brain increased due to AlCl3-mediated inflammation, which Vitamin K2 prevented. The acetylcholine esterase and oxidative stress markers induced by AlCl3 were reversed by Vitamin K2. Also, Vitamin K2 helps to restore hippocampal BDNF levels and reduced the amyloid β accumulation in AlCl3-administered animals. Additionally, Vitamin K2 protected the hippocampal neurons against AlCl3-mediated damage as observed in histopathological studies. We conclude that Vitamin K2 could partially reverse AlCl3-mediated cognitive decline. It increases acetylcholine and BDNF levels while reducing oxidative stress, neuroinflammation, and β-amyloid deposition, thus protecting the hippocampal neurons from AlCl3-mediated damage.

Multi-session transcutaneous auricular vagus nerve stimulation for Parkinson's disease: evaluating feasibility, safety, and preliminary efficacy.

In pre-clinical animal models of Parkinson's disease (PD), vagus nerve stimulation (VNS) can rescue motor deficits and protect susceptible neuronal populations. Transcutaneous auricular vagus nerve stimulation (taVNS) has emerged as a non-invasive alternative to traditional invasive cervical VNS. This is the first report summarizing the safety, feasibility, and preliminary efficacy of repeated sessions of taVNS in participants with PD. To evaluate the feasibility, safety, and possible efficacy of taVNS for motor and non-motor symptoms in mild to moderate PD. This is a double-blind, sham controlled RCT (NCT04157621) of taVNS in 30 subjects with mild to moderate PD without cognitive impairment. Participants received 10, 1-h taVNS sessions (25 Hz, 200% of sensory threshold, 500 μs pulse width, 60 s on and 30 s off) over a 2-week period. Primary outcome measures were feasibility and safety of the intervention; secondary outcomes included the MDS-UPDRS, cognitive function and self-reported symptom improvement. taVNS treatment was feasible, however, daily in-office visits were reported as being burdensome for participants. While five participants in the taVNS group and three in the sham group self-reported one or more minor adverse events, no major adverse events occurred. There were no group differences on blood pressure and heart rate throughout the intervention. There were no group differences in MDS-UPDRS scores or self-reported measures. Although global cognitive scores remained stable across groups, there was a reduction in verbal fluency within the taVNS group. taVNS was safe, and well-tolerated in PD participants. Future studies of taVNS for PD should explore at-home stimulation devices and optimize stimulation parameters to reduce variability and maximize engagement of neural targets.

Establishment and identification of an animal model of Hirschsprung disease in suckling mice

BackgroundHirschsprung disease (HSCR) is a congenital intestinal malformation. Previous HSCR animal model needs invasive operation on adult animal. The aim of this study is to establish an early-onset animal model which is consistent with the clinical manifestation of HSCR patients.MethodsThe neonatal mice were randomly divided into the benzalkonium chloride (BAC) group, treated with BAC via enema, and the control group, treated with saline. Weight changes, excretion time of carmine, CT scan, hematoxylin-eosin staining and immunofluorescence staining were used to evaluate the effect of the model. Differentially expressed genes (DEGs) in the HSCR mice were analyzed by using DAVID 6.8 database and compared with DEGs from HSCR patients.ResultsThe weight of mice was lower and the excretion time of carmine was longer in the BAC group. Moreover, distal colon stenosis and proximal colon enlargement appeared in the BAC group. Neurons in the distal colon decreased significantly after 4 weeks of BAC treatment and almost disappeared completely after 12 weeks. Transcriptome profiling of the mouse model and HSCR patients is similar in terms of altered gene expression.ConclusionsAn economical and reliable HSCR animal model which has similar clinical characteristics to HSCR patients was successfully established.ImpactThe animal model of Hirschsprung disease was first established in BALB/c mice.This model is an animal model of early-onset HSCR that is easy to operate and consistent with clinical manifestations.Transcriptome profiling of the mouse model and HSCR patients is similar in terms of altered gene expression.

Repurposing drugs to treat trichinellosis: in vitro analysis of the anthelmintic activity of nifedipine and Chrysanthemum coronarium extract

Albendazole is the most common benzimidazole derivative used for trichinellosis treatment but has many drawbacks. The quest for alternative compounds is, therefore, a target for researchers. This work aims to assess the in vitro anthelmintic effect of nifedipine, a calcium channel blocker, and a methanol extract of the flowers of Chrysanthemum coronarium as therapeutic repurposed drugs for treating different developmental stages of Trichinella spiralis in comparison with the reference drug, albendazole. Adult worms and muscle larvae of Trichinella spiralis were incubated with different concentrations of the studied drugs. Drug effects were evaluated by parasitological and electron microscopic examination.As a result, the effects of these drugs on muscle larvae were time and dose-dependent. Moreover, the LC50 after 48 h incubation was 81.25 µg/ml for albendazole, 1.24 µg/ml for nifedipine, and 229.48 µg/ml for C. coronarium. Also, the effects of the tested drugs were prominent on adult worms as the LC50 was 89.77 µg/ml for albendazole, 1.87 µg/ml for nifedipine, and 124.66 µg/ml for C. coronarium. SEM examination of the tegument of T. spiralis adult worms and larvae showed destruction of the adult worms' tegument in all treated groups. The tegument morphological changes were in the form of marked swellings or whole body collapse with the disappearance of internal contents. Furthermore, in silico studies showed that nifedipine might act as a T. spiralis β-tubulin polymerization inhibitor.Our results suggest that nifedipine and C. coronarium extract may be useful therapeutic agents for treating trichinellosis and warrant further assessment in animal disease models.

The Effects of Carvacrol on Transient Receptor Potential (TRP) Channels in an Animal Model of Parkinson's Disease.

In this study, we aimed to investigate the effects of carvacrol (CA), a widely used phytochemical having anti-oxidant and neuroprotective effects, on transient receptor potential (TRP) channels in an animal model of Parkinson's disease (PD). A total of 64 adult male Spraque-Dawley rats were divided into four groups: sham-operated, PD animal model (unilateral intrastriatal injections of 6-hydroxydopamine (6-OHDA), 6µg/µl), PD + vehicle (dimethyl sulfoxide (DMSO)) treatment, and PD + CA treatment (10mg/kg, every other day, for 14days). Half of the brain samples of substantia nigra pars compacta (SNpc) and striatum (CPu) were collected for immunohistochemistry and the remaining half were used for molecular analyses. CA treatment significantly increased the density of dopaminergic neurons immunolabeled with tyrosine hydroxylase and transient receptor potential canonical 1 (TRPC1) channel in the SNpc of PD animals. In contrast, the density of astrocytes immunolabeled with glial fibrillary acetic acid and transient receptor potential ankyrin 1 (TRPA1) channel significantly decreased following CA treatment in the CPu of PD animals. RT-PCR and western blot analyses showed that 6-OHDA administration significantly reduced TRPA1 and TPRPC1 mRNA expression and protein levels in both SNpc and CPu. CA treatment significantly upregulated TRPA1 expression in PD group, while TRPC1 levels did not display an alteration. Based on this data it was concluded that CA treatment might protect the number of dopaminergic neurons by reducing the reactive astrogliosis and modulating the expression of TRP channels in both neurons and astrocytes in an animal model of PD.

Polygenic genetic variation affecting antibody formation underlies hypertensive renal injury in the stroke-prone spontaneously hypertensive rat.

During development of the spontaneously hypertensive rat (SHR), several distinct but closely related lines were generated. Most lines are resistant to hypertensive renal disease. However, the SHR-A3 line (stroke-prone SHR) experiences end-organ injury (EOI) and provides a model of injury susceptibility that can be used to uncover genetic causation. In the present study, we generated a congenic line in which three distinct disease loci in SHR-A3 are concurrently replaced with homologous loci from an injury-resistant SHR line (SHR-B2). Verification that all three loci were homozygously replaced in this triple congenic line [SHR-A3(Trip B2)] while the genetic background of SHR-A3 was fully retained was obtained by whole genome sequencing. Congenic genome substitution was without effect on systolic blood pressure [198.9 ± 3.34 mmHg, mean ± SE, SHR-A3(Trip B2) = 194.7 ± 2.55 mmHg]. Measures of renal injury (albuminuria, histological injury scores, and urinary biomarker levels) were reduced in SHR-A3(Trip B2) animals, even though only 4.5 Mbases of the 2.8 Gbases of the SHR-B2 genome (0.16% of the genome) was transferred into the congenic line. The gene content of the three congenic loci and the functional effects of gene polymorphism within suggest a role of immunoglobulin in EOI pathogenesis. To prove the role of antibodies in EOI in SHR-A3, we generated an SHR-A3 line in which expression from the immunoglobulin heavy chain gene was knocked out (SHR-A3-IGHKO). Animals in the SHR-A3-IGHKO line lack B cells and immunoglobulin, but the hypertensive phenotype is not affected. Renal injury, however, was reduced in this line, confirming a pathogenic role for immunoglobulin in hypertensive EOI in this model of heritable risk.NEW & NOTEWORTHY Here, we used a polygenic animal model of hypertensive renal disease to show that genetic variation affecting antibody formation underlies hypertensive renal disease. We proved the genetic thesis by generating an immunoglobulin knockout in the susceptible animal model.

A novel co-culture model for investigation of the effects of LPS-induced macrophage-derived cytokines on brain endothelial cells.

In order to study effects of macrophage-derived inflammatory mediators associated with systemic inflammation on brain endothelial cells, we have established a co-culture system consisting of bEnd.3 cells and LPS-activated Raw 264.7 cells and performed its cytokine profiling. The cytokine profile of the co-culture model was compared to that of mice treated with intraperitoneal LPS injection. We found that, among cytokines profiled, eight cytokines/chemokines were similarly upregulated in both in vivo mouse and in vitro co-culture model. In contrast to the co-culture model, the cytokine profile of a common mono-culture system consisting of only LPS-activated bEnd.3 cells had little similarity to that of the in vivo mouse model. These results indicate that the co-culture of bEnd.3 cells with LPS-activated Raw 264.7 cells is a better model than the common mono-culture of LPS-activated bEnd.3 cells to investigate the molecular mechanism in endothelial cells, by which systemic inflammation induces neuroinflammation. Moreover, fibrinogen adherence both to bEnd.3 cells in the co-culture and to brain blood vessels in a LPS-treated animal model of Alzheimer's disease increased. To the best of our knowledge, this is the first to utilize bEnd.3 cells co-cultured with LPS-activated Raw 264.7 cells as an in vitro model to investigate the consequence of macrophage-derived inflammatory mediators on brain endothelial cells.

Effects of Soya Beans and Brown Beans in Degenerative Changes Expressed in Cortical Neun Immunoreactivity in a Casava-Induced Konzo Disease Rat Model

Background: Konzo is related to a habit of long-term consumption of cassava; it is a chronic disease with quite different symptoms from acute cassava poisoning. The ameliorative effect of soya beans and brown beans in degenerative changes expressed in cortical NeuN immunoreactivity in a konzo disease rat model was investigated in the present study. Materials and Methods: 30 male wistar rats weighing 200-250g were assigned to Group 1 (Control, n=5) and was fed on animal pellet, whereas Group 2 (Protein, n=5) was administered with protein food (Soya beans+Brown bean). Bitter cassava flour was provided to Group 3 (cassava-induced Konzo, n=15). Protein (Soya beans+Brown bean) and bitter cassava flour were administered to Group 4 (protein treatment group, n=5). The Cerebrum (primary motor cortex) region was harvested through transcardiac perfusion for histological and immunohistochemical staining. Image J was used to quantify the neurons in the motor cortex. We examined general structures in the primary motor cortex with hematoxylin and eosin (H&E) stain. Result and Discussion: H&E demonstration showed distinct pyramidal neurons with large round nucleus, and prominent nucleoli in the Control group. Interspersed between the pyramidal neurons were numerous glia cells. Protein (Soya beans+Brown bean) group, Cassava group, and Cassava + Protein group also showed intact histology of the cortex compared to control usig H&E stain. NeuN stains analyzed immunoreactive neurons. The rats fed on cassava showed significant decrease in the NeuN immunoreactive neurons at ***[p<.001] compared to the Control and Protein administered group, whereas Cassava + Protein groups showed decrease NeuN immunoreactive neurons at**p<0.1 compared to Protein group(Soya beans+Brown bean). Conclusions: This study has provided an empirical data on the ameliorative effect of soya beans and brown beans supplement on Cassava-induced konzo disease animal model. This data will be very useful to Anatomists, konzo researchers and neuroscientist.

LPS priming before plaque deposition impedes microglial activation and restrains Aβ pathology in the 5xFAD mouse model of Alzheimer’s disease

Microglia have an innate immunity memory (IIM) with divergent functions in different animal models of neurodegenerative diseases, including Alzheimer’s disease (AD). AD is characterized by chronic neuroinflammation, neurodegeneration, tau tangles and β-amyloid (Aβ) deposition. Systemic inflammation has been implicated in contributing to the progression of AD. Multiple reports have demonstrated unique microglial signatures in AD mouse models and patients. However, the proteomic profiles of microglia modified by IIM have not been well-documented in an AD model. Therefore, in the present study, we investigate whether lipopolysaccharide (LPS)-induced IIM in the pre-clinical stage of AD alters the microglial responses and shapes the neuropathology. We accomplished this by priming 5xFAD and wild-type (WT) mice with an LPS injection at 6 weeks (before the robust development of plaques). 140 days later, we evaluated microglial morphology, activation, the microglial barrier around Aβ, and Aβ deposition in both 5xFAD primed and unprimed mice. Priming induced decreased soma size of microglia and reduced colocalization of PSD95 and Synaptophysin in the retrosplenial cortex. Priming appeared to increase phagocytosis of Aβ, resulting in fewer Thioflavin S+ Aβ fibrils in the dentate gyrus. RIPA-soluble Aβ 40 and 42 were significantly reduced in Primed-5xFAD mice leading to a smaller size of MOAB2+ Aβ plaques in the prefrontal cortex. We also found that Aβ-associated microglia in the Primed-5xFAD mice were less activated and fewer in number. After priming, we also observed improved memory performance in 5xFAD. To further elucidate the molecular mechanism underlying these changes, we performed quantitative proteomic analysis of microglia and bone marrow monocytes. A specific pattern in the microglial proteome was revealed in primed 5xFAD mice. These results suggest that the imprint signatures of primed microglia display a distinctive phenotype and highlight the potential for a beneficial adaption of microglia when intervention occurs in the pre-clinical stage of AD.

Retinal vascular remodeling in photoreceptor degenerative disease

Abnormal vasculature in the retina, specifically tortuous vessels and capillary degeneration, is common in many of the most prevalent retinal degenerative diseases, currently affecting millions of people across the world. However, the formation and development of abnormal vasculature in the context of retinal degenerative diseases are still poorly understood. The FVB/N (rd1) and rd10 mice are well-studied animal models of retinal degenerative diseases, but how photoreceptor degeneration leads to vascular abnormality in the diseases remains to be elucidated. Here, we used advancements in confocal microscopy, immunohistochemistry, and image analysis software to systematically characterize the pathological vasculature in the FVB/N (rd1) and rd10 mice, known as a chronic, rapid and slower retinal degenerative model, respectively. We demonstrated that there was plexus-specific vascular degeneration in the retinal trilaminar vascular network paralleled to photoreceptor degeneration in the diseased retinas. We also quantitatively analyzed the vascular structural architecture in the wild-type and diseased retinas to provide valuable information on vascular remodeling in retinal degenerative disease.

Therapeutic properties of Helicobacter pylori-derived vacuolating cytotoxin A in an animal model of chronic allergic airway disease

BackgroundIt has previously been shown that the Helicobacter pylori (H. pylori)-derived molecule vacuolating cytotoxin A (VacA) could be suitable for the treatment of allergic airway disease. The therapeutic activity of the protein, which acts through modulation of dendritic cells (DC) and regulatory T cells (Tregs), was demonstrated in murine short-term acute models. The aim of this study is to further evaluate the therapeutic potential of VacA by determining the effectiveness of different application routes and the suitability of the protein for treating the chronic phase of allergic airway disease.MethodsVacA was administered by the intraperitoneal (i.p.), oral (p.o.) or intratracheal (i.t.) routes, and long-term therapeutic effectiveness, allergic airway disease hallmarks, and immune phenotype were analyzed in murine models of acute and chronic allergic airway disease.ResultsAdministration of VacA via the i.p., p.o or i.t. routes was associated with a reduction in airway inflammation. The i.p. route showed the most consistent effect in reducing airway inflammation and i.p. treatment with VacA was the only treatment that significantly reduced mucus cell hyperplasia. In a murine model of chronic allergic airway disease, both short- and long-term treatment with VacA showed a therapeutic effect, with a reduction in a variety of asthma hallmarks, including bronchoalveolar lavage eosinophilia, lung inflammation and goblet cell metaplasia. Short-term treatment was associated with induction of Tregs, while repetitive long-term administration of VacA influenced immunological memory in the lung.ConclusionsIn addition to showing therapeutic efficacy in short-term models, treatment with VacA also appeared to be effective in suppressing inflammation in a chronic airway disease model. The observation that treatment was effective after administration via several different routes highlights the potential of VacA as a therapeutic agent with different routes of administration in humans.

Neural circuit and synaptic dysfunctions in ALS-FTD pathology.

Action selection is a capital feature of cognition that guides behavior in processes that range from motor patterns to executive functions. Here, the ongoing actions need to be monitored and adjusted in response to sensory stimuli to increase the chances of reaching the goal. As higher hierarchical processes, these functions rely on complex neural circuits, and connective loops found within the brain and the spinal cord. Successful execution of motor behaviors depends, first, on proper selection of actions, and second, on implementation of motor commands. Thus, pathological conditions crucially affecting the integrity and preservation of these circuits and their connectivity will heavily impact goal-oriented motor behaviors. Amyotrophic Lateral Sclerosis (ALS) and Frontotemporal Dementia (FTD) are two neurodegenerative disorders known to share disease etiology and pathophysiology. New evidence in the field of ALS-FTD has shown degeneration of specific neural circuits and alterations in synaptic connectivity, contributing to neuronal degeneration, which leads to the impairment of motor commands and executive functions. This evidence is based on studies performed on animal models of disease, post-mortem tissue, and patient derived stem cells. In the present work, we review the existing evidence supporting pathological loss of connectivity and selective impairment of neural circuits in ALS and FTD, two diseases which share strong genetic causes and impairment in motor and executive functions.

[Conditioning of the immune system-Already clinically usable?]

The brain and the immune system permanently exchange information via various neuronal and humoral signaling pathways. This communication network forms the basis for controlling peripheral immune functions via associative learning or conditioning processes. Establishing a learned immune reaction, an immunomodulatory drug that represents the unconditioned stimulus (US) is paired with a new odor or taste stimulus. Re-presentating this previously neutral odor or taste stimulus, its now functions as aconditioned stimulus (CS) and triggers reactions in the immune system similar to those formerly induced by the drug used as US. Using different learning protocols, it was possible to condition immunopharmacological effects in animal disease models, such as lupus erythematosus, contact allergy or rheumatoid arthritis, thereby reducing disease symptoms. Preliminary experimental studies in healthy volunteers and patients confirmed a possible clinical use of learned immune responses with the aim of using associative learning protocols as complementary measures to pharmacological interventions in clinical practice in order to reduce drug doses and thus undesirable drug side effects while maintaining therapeutic efficacy. However, there is still agreat need for further research to understand the mechanisms of learned immune responses in preclinical studies and to optimize the associative learning processes for using them in the clinical routine in studies with healthy volunteers and patients.

CRISPR/Cas Systems for Therapeutic Purposes: Applications in Disease Prevention, Mechanism Study, and Treatment

CRISPR/Cas systems were novel multifunctional genome editing techniques, and the modification of Cas proteins endowed them with more efficient and precise properties. Herein, we systematically outlined the principles and applications of CRISPR/Cas systems in disease prevention, mechanism research, and gene treatment of diseases. Specifically, we detailed the systems widely utilized, containing the Cas9, Cas12a, and Cas13a systems, and summarized the current status of the medical applications of these systems in terms of vaccine design, trait improvement, animal models of human diseases, organ transplantation, gene therapy, and gene detection. We concluded that CRISPR/Cas systems had great potential to advance medical research and practice but also should be carefully regulated and supervised to ensure their safety and efficacy.

Interspecies comparison of temporomandibular joint condylar cartilage extracellular matrix from macro to microscopy

Interspecies comparisons of the extracellular matrix of temporomandibular joint (TMJ) condylar cartilage are necessary to elucidate the mechanisms underlying its superior mechanical properties, to guide the construction of animal models of TMJ-related diseases, and to establish standards for the engineering of TMJ condylar cartilage. Here we characterize and compare TMJ condylar cartilage from six different species from a materials science perspective, including structure, composition and mechanical properties from the macroscopic to the microscopic level. The gross morphology showed obvious interspecies differences in size and shape, which may be related to the different joint motion patterns. Although the condylar cartilage of all species can be divided histologically into a superficial fibrous layer and a deep hyaline layer, there are significant interspecies differences in the microstructure of the fibrils in the two layers, mainly in the diameter of the fibrils. Compositionally, there were no significant differences in collagen composition between species, but the content of glycosaminoglycans (GAGs) decreased progressively with increasing body size, with the same results obtained by Safranin O staining and biochemical analysis. Mechanically, the elastic modulus of mouse condylar cartilage was significantly higher than that of the other species and tended to decrease with increasing body size. This study shows that the TMJ condylar cartilage of different species has its own specific structure-composition-mechanics matching characteristics for their unique masticatory stress dissipation, and differences in fibril diameter and GAGs content may be the two ultimate factors influencing the differences in cartilage mechanical properties between species, while the condylar cartilage of pigs is most similar to that of humans, suggesting that pigs may be a suitable animal model for TMJ studies.

Alterations in retinal pulse wave velocity under experimental ocular hypertension.

Impairments of blood flow and autoregulation have been implicated in diabetic retinopathy and glaucoma. Thus, identifying biomarkers of retinal vascular compliance and regulatory capacity is of potential value for understanding the pathophysiology and evaluating onset or progression of disease. Pulse wave velocity (PWV) represents the speed of the pulse-propagated pressure wave within blood vessels and has shown promise as a marker of vascular compliance. The purpose of the current study was to report a method for comprehensive assessment of retinal PWV based on spectral analysis of pulsatile intravascular intensity waveforms and determine alterations due to experimental ocular hypertension. Retinal PWV was linearly related to vessel diameter. Increased retinal PWV was associated with elevated intraocular pressure. Retinal PWV has the potential to serve as a vasoregulation biomarker for investigating vascular factors that contribute to the development of retinal diseases in animal models.