Trophoblast organoids can provide crucial insights into mechanisms of placentation, however their potential is limited by highly variable extracellular matrices unable to reflect in vivo tissues. Here, we present a bioprinted placental organoid model, generated using the first trimester trophoblast cell line, ACH-3P, and a synthetic polyethylene glycol (PEG) matrix. Bioprinted or Matrigel-embedded organoids differentiate spontaneously from cytotrophoblasts into two major subtypes: extravillous trophoblasts (EVTs) and syncytiotrophoblasts (STBs). Bioprinted organoids are driven towards EVT differentiation and show close similarity with early human placenta or primary trophoblast organoids. Inflammation inhibits proliferation and STBs within bioprinted organoids, which aspirin or metformin (0.5 mM) cannot rescue. We reverse the inside-out architecture of ACH-3P organoids by suspension culture with STBs forming on the outer layer of organoids, reflecting placental tissue. Our bioprinted methodology is applicable to trophoblast stem cells. We present a high-throughput, automated, and tuneable trophoblast organoid model that reproducibly mimics the placental microenvironment in health and disease.
Spinal cord injuries (SCI) can occur from either traumatic or non-traumatic causes. While traumatic spinal cord injury (TSCI), caused by acute external forces, is well-researched, non-traumatic spinal cord injury (NTSCI), arising from chronic conditions like tumors and infections, is often underreported and misclassified. NTSCI is increasingly recognized as a major cause of SCI globally, particularly affecting the elderly and infants. Despite its prevalence, research on NTSCI remains limited, necessitating new models to understand its pathophysiology. This study introduces a novel, repeatable model for NTSCI in both neonatal (9 days post-partum) and adult rats (9 weeks post-partum), simulating chronic compression injuries. The model uses 3D-printed (PLA) spacers to induce mild-moderate compression in the lower thoracic vertebrae. Six weeks of spinal cord compression resulted in locomotor deficits and cellular changes consistent with hypoxic-ischemic injury due to disrupted blood flow, without significant long-term inflammation or astrogliosis. This versatile model can be easily adapted for different age groups, for graded injury severities, and for different injury durations. It offers a promising avenue for understanding and treating chronic compression NTSCI, addressing a critical gap in current research. This model can be used in future research to test and understand the effectiveness and pathophysiology of decompression and cellular interventions in response to chronic compression NTSCI.
Indoor vaping can lead to third-hand vapour exposure, evidenced by the presence of nicotine and carcinogenic nitrosamines on indoor surfaces. Children are at high risk of such exposure. This study aimed to investigate the effects of third-hand vapour exposure on cognitive function in young mice. Male mice (Balb/c, 4 weeks) were exposed to cotton towels treated with e-cigarette vapour with and without nicotine (9 L chamber filled with 20 puffs of vapour for 2 hours) and changed daily for four weeks. Vapour was generated from tobacco-flavoured e-cigarette liquids (50 % propylene glycol, 50 % vegetable glycerine, 18 mg or 0 mg nicotine) using a human e-cigarette device. Mice exposed to nicotine-free vapour showed impaired short-term memory, while those exposed to nicotine-containing vapour exhibited significantly increased anxiety-like behaviours. Both exposure groups had reduced neuron numbers in the cortex and increased microglia numbers and pro-inflammatory cytokine expression in the brain. Third-hand exposure to vapour can impair memory function and increase anxiety, with some effects being nicotine-independent. These findings highlight the potential risks of indoor vaping, especially in environments frequented by younger people, including children and adolescents, and the need for further research to identify the underlying mechanisms. Synopsis: This is the first study highlighting the risks of cognitive impairment due to third-hand exposure to e-cigarette residues in a mouse model.
Memory function is critically essential across all life stages, yet it is increasingly compromised by exposure to airborne pollutants due to human behaviours. This review examines the adverse impacts of tobacco smoke and e-cigarette vapour on memory function, emphasising the risks to younger populations. Both pollutants are potent oxidants that induce oxidative stress and inflammatory responses in the brain, leading to synaptic injury and neuronal apoptosis. These processes compromise neuronal integrity and function, potentially resulting in early-onset dementia. Additionally, third-hand exposure to tobacco smoke and e-cigarette vapour, through re-exposure to toxic chemicals on surfaces or clothing, poses significant risks, especially to toddlers. Epigenetic mechanisms, including DNA methylation and histone modification, further exacerbate these effects by altering gene expression critical for brain development and function. This review highlights the necessity for further research to develop risk-reduction strategies to protect cognitive health from these pollutants.
Encapsulins, self-assembling protein nanocages derived from prokaryotes, are promising nanoparticle-based drug delivery systems (NDDS). However, the in vivo behavior and fate of encapsulins are poorly understood. In this pre-clinical study, we probe the interactions between the model encapsulin from Thermotoga maritima (TmEnc) and key biological barriers encountered by NDDS. Here, a purified TmEnc formulation that exhibited colloidal stability, storability, and blood compatibility was intravenously injected into BALB/c mice. TmEnc had an excellent nanosafety profile, with no abnormal weight loss or gross pathology observed, and only temporary alterations in toxicity biomarkers detected. Notably, TmEnc demonstrated immunogenic properties, inducing the generation of nanocage-specific IgM and IgG antibodies, but without any prolonged pro-inflammatory effects. An absence of antibody cross-reactivity also suggested immune-orthogonality among encapsulins systems. Moreover, TmEnc formed a serum-derived protein corona on its surface which changed dynamically and appeared to play a role in immune recognition. TmEnc’s biodistribution profile further revealed its sequestration from the blood circulation by the liver and then biodegraded within Kupffer cells, thus indicating clearance via the mononuclear phagocyte system. Collectively, these findings provide critical insights into how encapsulins behave in vivo, thereby informing their future design, modification, and application in targeted drug delivery.
Background: Spinal cord injury presents a significant burden globally, with traumatic spinal cord injury being the predominant cause historically. However, nontraumatic spinal cord injury (NTSCI) is emerging as a significant contributor, particularly in devel-oped nations, yet it remains poorly understood due to underreporting and misclassifi-cation. NTSCI, spanning various etiologies such as bony growths, vascular conditions, infections, neoplastic conditions, and immune disorders, poses unique challenges in diagnosis and treatment, often resulting in lifelong morbidity. This study addresses the lack of suitable animal models for NTSCI research, especially in neonatal animals. Methods: Utilizing a solid spacer approach, we developed a compression NTSCI model applicable to both neonatal and adult Sprague-Dawley rats. Results: Through anatomical measurements and in vivo experiments, we confirmed the feasibility and safety of the spacer insertion procedure and observed no acute off- target effects. Conclusion: The versatility of this model lies in its adaptability to different ages of rats, offering a cost-effective and reproducible means to induce graded injuries. Moreover, behavioral assessments demonstrated observable hindlimb function, validating the model's utility for studying functional outcomes. Although challenges persist, par-ticularly in accounting for spinal column growth in neonatal animals, this model fills a crucial gap in pediatric NTSCI research. By providing a platform to investigate patho-physiological mechanisms and test potential treatments, it offers promising avenues for advancing our understanding and management of pediatric NTSCI
Previous evidence shows that rapid changes occur in the brain following spinal cord injury (SCI). Here, we interrogated the expression of the neuropeptides pituitary adenylyl cyclase-activating peptide (PACAP), vasoactive intestinal peptides (VIP), and their binding receptors in the rat brain 24 h following SCI. Female Sprague-Dawley rats underwent thoracic laminectomy; half of the rats received a mild contusion injury at the level of the T10 vertebrate (SCI group); the other half underwent sham surgery (sham group). Twenty-four hours post-surgery, the hypothalamus, thalamus, amygdala, hippocampus (dorsal and ventral), prefrontal cortex, and periaqueductal gray were collected. PACAP, VIP, PAC1, VPAC1, and VPAC2 mRNA and protein levels were measured by real-time quantitative polymerase chain reaction and Western blot. In SCI rats, PACAP expression was increased in the hypothalamus (104-141% vs sham) and amygdala (138-350%), but downregulated in the thalamus (35-95%) and periaqueductal gray (58-68%). VIP expression was increased only in the thalamus (175-385%), with a reduction in the amygdala (51-68%), hippocampus (40-75%), and periaqueductal gray (74-76%). The expression of the PAC1 receptor was the least disturbed by SCI, with decrease expression in the ventral hippocampus (63-68%) only. The expression levels of VPAC1 and VPAC2 receptors were globally reduced, with more prominent reductions of VPAC1 vs VPAC2 in the amygdala (21-70%) and ventral hippocampus (72-75%). In addition, VPAC1 downregulation also extended to the dorsal hippocampus (69-70%). These findings demonstrate that as early as 24 h post-SCI, there are region-specific disruptions of PACAP, VIP, and related receptor transcript and protein levels in supraspinal regions controlling higher cognitive functions.
Background:Adipose-derived stem cells (ADSCs) are increasingly utilised in the field of neural regeneration due to their high accessibility and capacity for differentiation into neural like cells. Culturing ADSCs in the presence of various growth factors, small molecules and combinations thereof have shown promise in this regard; however, these protocols are generally complex, time-consuming and costly. The need for commercially available and chemically defined growth media/supplements is required to facilitate further developments in this area.Methods:In this study, we have examined the neural differentiation and proliferation potential of the commercially available supplements B27, CultureOne (C1) and N2 on human ADSCs (hADSCs). Through a combination of immunocytochemistry, cytokine analysis, and CNPase enzymatic assays, we provide novel insight into the neural differentiation effects of B27, C1 and N2 on hADSCs.Results:The study found that C1 and N2 supplements initiated neural differentiation of the cells, with C1 pushing differentiation towards an oligodendrocytic lineage and N2 initiating neuronal differentiation. This suggests that C1 and N2 supplements can be used to drive neural differentiation in hADSCs. However, B27 did not show significant differentiation in the time frame in which the experiments took place and therefore is unsuitable for this purpose.Conclusions:These findings highlight the utility of commercially available supplements in the neural differentiation of ADSCs and may assist in establishing simpler, more affordable differentiation protocols.
Preeclampsia is a pregnancy-specific cardiovascular disorder, involving significant maternal endothelial dysfunction. Although inappropriate placentation due to aberrant angiogenesis, inflammation and shallow trophoblast invasion are the root causes of preeclampsia, pathogenic mechanisms are poorly understood, particularly in early pregnancy. Here, we first confirm the abnormal expression of important vascular and inflammatory proteins, FK506-binding protein-like (FKBPL) and galectin-3 (Gal-3), in human plasma and placental tissues from women with preeclampsia and normotensive controls. We then employ a three-dimensional microfluidic placental model incorporating human umbilical vein endothelial cells (HUVECs) and a first trimester trophoblast cell line (ACH-3P) to investigate FKBPL and Gal-3 signaling in inflammatory conditions. In human samples, both circulating ( n = 17 controls; n = 30 preeclampsia) and placental ( n ≥ 6) FKBPL and Gal-3 levels were increased in preeclampsia compared to controls (plasma: FKBPL, p < 0.0001; Gal-3, p < 0.01; placenta: FKBPL, p < 0.05; Gal-3, p < 0.01), indicative of vascular dysfunction in preeclampsia. In our placenta-on-a-chip model, we show that endothelial cells are critical for trophoblast-mediated migration and that trophoblasts effectively remodel endothelial vascular networks. Inflammatory cytokine tumour necrosis factor-α (10 ng/mL) modulates both FKBPL and Gal-3 signaling in conjunction with trophoblast migration and impairs vascular network formation ( p < 0.005). Our placenta-on-a-chip recapitulates aspects of inappropriate placental development and vascular dysfunction in preeclampsia.
Neurological diseases are among the leading causes of disability and death worldwide and remain difficult to treat. Tissue engineering offers avenues to test potential treatments; however, the development of biologically accurate models of brain tissues remains challenging. Given their neurogenic potential and availability, adipose-derived stem cells (ADSCs) are of interest for creating neural models. While progress has been made in differentiating ADSCs into neural cells, their differentiation in 3D environments, which are more representative of the in vivo physiological conditions of the nervous system, is crucial. This can be achieved by modulating the 3D matrix composition and stiffness. Human ADSCs were cultured for 14 days in a 1.1 kPa polyethylene glycol-based 3D hydrogel matrix to assess effects on cell morphology, cell viability, proteome changes and spontaneous neural differentiation. Results showed that cells continued to proliferate over the 14-day period and presented a different morphology to 2D cultures, with the cells elongating and aligning with one another. The proteome analysis revealed 439 proteins changed in abundance by >1.5 fold. Cyclic nucleotide 3′-phosphodiesterase (CNPase) markers were identified using immunocytochemistry and confirmed with proteomics. Findings indicate that ADSCs spontaneously increase neural marker expression when grown in an environment with similar mechanical properties to the central nervous system.
Cardiovascular disease (CVD) is a leading cause of mortality worldwide, with cigarette smoking being a major preventable risk factor. Smoking cessation can be difficult due to the addictive nature of nicotine and the withdrawal symptoms following cessation. Electronic cigarettes (e-Cigs) have emerged as an alternative smoking cessation device, which has been increasingly used by non-smokers; however, the cardiovascular effects surrounding the use of e-Cigs remains unclear. This study aimed to investigate the effects of e-Cig aerosol condensate (EAC) (0 mg and 18 mg nicotine) in vitro on human coronary artery endothelial cells (HCAEC) and in vivo on the cardiovascular system using a mouse model of ‘e-vaping’. In vitro results show a decrease in cell viability of HCAEC when exposed to EAC either directly or after exposure to conditioned lung cell media (p < 0.05 vs. control). Reactive oxygen species were increased in HCAEC when exposed to EAC directly or after exposure to conditioned lung cell media (p < 0.0001 vs. control). ICAM-1 protein expression levels were increased after exposure to conditioned lung cell media (18 mg vs. control, p < 0.01). Ex vivo results show an increase in the mRNA levels of anti-angiogenic marker, FKBPL (p < 0.05 vs. sham), and endothelial cell adhesion molecule involved in barrier function, ICAM-1 (p < 0.05 vs. sham) in murine hearts following exposure to electronic cigarette aerosol treatment containing a higher amount of nicotine. Immunohistochemistry also revealed an upregulation of FKBPL and ICAM-1 protein expression levels. This study showed that despite e-Cigs being widely used for tobacco smoking cessation, these can negatively impact endothelial cell health with a potential to lead to the development of cardiovascular disease.
Adipose-derived stem cells (ADSCs) have incredible potential as an avenue to better understand and treat neurological disorders. While they have been successfully differentiated into neural stem cells and neurons, most such protocols involve 2D environments, which are not representative of in vivo physiology. In this study, human ADSCs were cultured in 1.1 kPa polyethylene-glycol 3D hydrogels for 10 days with B27, CultureOne (C1), and N2 neural supplements to examine the neural differentiation potential of ADSCs using both chemical and mechanical cues. Following treatment, cell viability, proliferation, morphology, and proteome changes were assessed. Results showed that cell viability was maintained during treatments, and while cells continued to proliferate over time, proliferation slowed down. Morphological changes between 3D untreated cells and treated cells were not observed. However, they were observed among 2D treatments, which exhibited cellular elongation and co-alignment. Proteome analysis showed changes consistent with early neural differentiation for B27 and C1 but not N2. No significant changes were detected using immunocytochemistry, potentially indicating a greater differentiation period was required. In conclusion, treatment of 3D-cultured ADSCs in PEG-based hydrogels with B27 and C1 further enhances neural marker expression, however, this was not observed using supplementation with N2.
Compression spinal cord injuries are a common cause of morbidity in people who experience a spinal cord injury (SCI). Either as a by-product of a traumatic injury or due to nontraumatic conditions such as cervical myelitis, compression injuries are growing in prevalence clinically and many attempts of animal replication have been described within the literature. These models, however, often focus on the traumatic side of injury or mimic short-term injuries that are not representative of the majority of compression SCI. Of this, nontraumatic spinal cord injuries are severely understudied and have an increased prevalence in elderly populations, adults, and children. Therefore, there is a need to critically evaluate the current animal models of compression SCI and their suitability as a method for clinically relevant data that can help reduce morbidity and mortality of SCI. In this review, we reviewed the established and emerging methods of animal models of compression SCI. These models are the clip, balloon, solid spacer, expanding polymer, remote, weight drop, calibrated forceps, screw, and strap methods. These methods showed that there is a large reliance on the use of laminectomy to induce injury. Furthermore, the age range of many studies does not reflect the elderly and young populations that commonly suffer from compression injuries. It is therefore important to have techniques and methods that are able to minimize secondary effects of the surgeries, and are representative of the clinical cases seen so that treatments and interventions can be developed that are specific.
Traumatic brain injury (TBI) and obesity are two common conditions in modern society; both can impair neuronal integrity and neurological function. However, it is unclear whether the coexistence of both conditions will worsen outcomes. Therefore, in a rat model, we aimed to investigate whether the coexistence of TBI and a high-fat diet (HFD) has an additive effect, leading to more severe neurological impairments, and whether they are related to changes in brain protein markers of oxidative stress, inflammation, and synaptic plasticity. Sprague-Dawley rats (female, similar to 250 g) were divided into HFD (43% fat) and diet (CD) (17% fat) groups for 6 weeks. Within each dietary group, half underwent a TBI by a weight-drop device, and the other half underwent sham surgery. Short-term memory and sensory function were measured at 24 h, 1 week, 3 weeks, and 6 weeks post-TBI. Brain tissues were harvested at 24 h and 6 weeks post-TBI, and markers of oxidative stress, apoptosis, inflammation, and synaptic plasticity were measured via immunostaining and Western blotting. In rats without TBI, HFD increased the pre-synaptic protein synaptophysin. In rats with TBI, HFD resulted in worsened sensory and memory function, an increase in activated macrophages, and a decrease in the endogenous antioxidant manganese superoxide dismutase (MnSOD). Our findings suggest that the additive effect of HFD and TBI worsens short term memory and sensation deficits, and may be driven by enhanced oxidative stress and inflammation.
Evidence suggests that rapid changes to supporting glia may predispose individuals with spinal cord injury (SCI) to such comorbidities. Here, we interrogated the expression of astrocyte- and microglial-specific markers glial fibrillary acidic protein (GFAP) and ionized calcium binding adaptor molecule 1 (Iba1) in the rat brain in the first 24 hours following SCI. Female Sprague-Dawley rats underwent thoracic laminectomy; half of the rats received a mild contusion injury at the level of the T10 vertebral body (SCI group), the other half did not (Sham group). Twenty-four hours post-surgery the amygdala, periaqueductal grey, prefrontal cortex, hypothalamus, lateral thalamus, hippocampus (dorsal and ventral) in rats were collected. GFAP and Iba1 mRNA and protein levels were measured by real-time quantitative polymerase chain reaction and Western blot. In SCI rats, GFAP mRNA and protein expression increased in the amygdala and hypothalamus. In contrast, gene and protein expression decreased in the thalamus and dorsal hippocampus. Interestingly, Iba1 transcripts and proteins were significantly diminished only in the dorsal and ventral hippocampus, where gene expression diminished. These findings demonstrate that as early as 24 hours post-SCI there are region-specific disruptions of GFAP and Iba1 transcript and protein levels in higher brain regions. All procedures were approved by the University of Technology Sydney Institutional Animal Care and Ethics Committee (UTS ACEC13-0069).
"Response to: Candidates undertaking (invigilated) assessment online show no differences in performance compared to those undertaking assessment offline." Medical Teacher, ahead-of-print(ahead-of-print), p. 1
It has been reported that children may respond better than adults to a spinal cord injury (SCI) of similar severity. There are known biomechanical differences in the developing spinal cord that may contribute to this "infant lesion effect," but the underlying mechanisms are unknown. Using immunohistochemistry, we have previously demonstrated a different injury progression and immune cell response after a mild thoracic contusion SCI in infant rats, as compared to adult rats. Here, we investigated the acute inflammatory responses using flow cytometry and ELISA at 1 h, 24 h, and 1 week after SCI in neonatal (P7) and adult (9 weeks) rats, and locomotor recovery was examined for 6 weeks after injury. Adult rats exhibited a pronounced pro-inflammatory response characterized by neutrophils and M1-like macrophage infiltration and Th1 cytokine secretion. Neonatal rats exhibited a decreased pro-inflammatory response characterized by a higher proportion of M2-like macrophages and reduced Th1 cytokine responses, as compared to adults. These results suggest that the initial inflammatory response to SCI is predominantly anti-inflammatory in very young animals.
Research has attributed tissue damage post-traumatic brain injury (TBI) to two-pronged effects, increased reactive oxygen species (ROS) and impairment of endogenous antioxidant defence systems, underpinned by manganese superoxide dismutase (MnSOD). Novel antioxidant nitroxides have been shown to mimic MnSOD to ameliorate oxidative stress related disorders. This study aimed to investigate the effects of two nitroxides, CTMIO and DCTEIO, on the neurological outcomes following moderate TBI in rats induced by a weight drop device. The rats were immediately treated with CTMIO and DCTEIO (40 mM in drinking water) post-injury for up to 2 weeks. The brains were histologically examined at 24 h and 6 weeks post injury. DCTEIO reduced the lesion size at both 24h and 6 weeks, with normalised performance in sensory, motor and cognitive tests at 24h post-injury. Astrogliosis was heightened by DCTEIO at 24h and still elevated at 6 weeks in this group. In TBI brains, cellular damage was evident as reflected by changes in markers of mitophagy and autophagy (increased fission marker dynamin-related protein (Drp)-1, and autophagy marker light chain 3 (LC3)A/B and reduced fusion marker optic atrophy (Opa)-1). These were normalised by DCTEIO treatment. CTMIO, on the other hand, seems to be toxic to the injured brains, by increasing injury size at 6 weeks. In conclusion, DCTEIO significantly improved tissue repair and preserved neurological function in rats with TBI possibly via a mitophagy mechanism. This study provides evidence for DCTEIO as a promising new option to alleviate lesion severity after moderate TBI, which is not actively treated.