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Biology subjects

Vitale, G.

Publications and source records attributed to Vitale, G..

3 recordsLinked to original sources

Perinatal ischemic stroke impairs motor and cognitive development, muscle structure, and gut microbiota composition, with functional improvement following fecal microbiota transplantation in a mouse model

Perinatal ischemic stroke is an early developmental brain injury caused by obstruction of cerebral blood vessels and is a leading cause of cerebral palsy and cognitive disability in survivors. However, progress in understanding its impact on the brain and other organ systems, as well as in developing effective therapies, remains limited, in part due to the scarcity of relevant preclinical models. Here, we induced ischemic stroke via middle cerebral artery occlusion in perinatal mice and investigated its effects within and beyond the brain across development into adulthood. We found that perinatal stroke disrupted fine motor development and impaired memory. In addition, it induced structural alterations in skeletal muscle and significant changes in gut microbiota composition. Notably, gut-targeted intervention using fecal microbiota transplantation improved fine motor function. Our findings demonstrate, for the first time, the multisystem developmental impact of perinatal stroke, extending beyond the brain, and identify gut microbiota modulation as a promising and potentially safe therapeutic strategy to improve motor outcomes after stroke.

neuroscience↗

A stimuli-responsive ex vivo model of osteoarthritis demonstrates TLR4-mediated cartilage degradation and a Rapamycin-induced fast matrix recovery

BackgroundIn osteoarthritis (OA) TLR4 signaling leads to downstream activation of the phosphoinositide 3-kinases/ protein kinase B/ mammalian target of Rapamycin (PIK3/AKT/mTOR) pathway, a known modulator of autophagic mechanisms in chondrocytes. This paper focuses on creating a realistic ex vivo OA model that mimics elements of the pathophysiology of OA, allowing for further hypotheses-based investigations, and for use as a bench test for new therapeutic targets. ObjectiveTo study the downstream inflammatory and matrix changes in cartilage due to TLR4 signaling and the recovery achieved by a commonly used immunosuppressive drug, Rapamycin. MethodsIn an ex vivo 3D model based on healthy porcine cartilage explants, we mimicked the OA environment by LPS stimulation activating TLR4 signaling. Furthermore, we inhibited mTOR signaling via Rapamycin, which is accepted to attenuate the cartilage response to LPS-TLR4 activation. Histology and immunohistochemistry were used to evaluate the structural and biomolecular modifications driven by LPS and Rapamycin. ResultsThe explant model captured key features of OA, such as extracellular matrix degeneration and altered autophagy. The OA-like changes in the model were driven by TLR4 activation and mTOR signaling, well-known OA-related molecular pathways, and reversed by Rapamycin. ConclusionWe demonstrate that our explant model is responsive to LPS stimulation, leading to activation of OA-related biomolecular pathways, closely mimicking the native physiological processes. This evidence supports the potential of our model to act as a platform for OA studies, in particular related to the gut-joint axis in age-related OA, and for the screening of new disease-modifying molecules.

bioengineering↗

Biofabrication of an in situ hypoxia-delivery scaffold for cartilage regeneration

Osteoarthritis (OA) is a debilitating joint condition affecting millions of people worldwide, triggering painful chondral defects (CDs) that ultimately compromise the overarching patients quality of life. Currently, several reconstructive cartilage techniques (RCTs) (i.e.: Matrix-assisted Autologous Chondrocytes Implantation - MACI) has been developed to overcome the total joint replacement (TJR) limitations in the treatment of CDs. However, there is no consensus on the effectiveness of RCTs in the long term, as they do not provide adequate pro-regenerative stimuli to ensure complete CDs healing. In this study, we describe the biofabrication of an innovative scaffold capable to promote the CDs healing by delivering pro-regenerative hypoxic cues at the cellular/tissue level, to be used during RCTs. The scaffold is composed of a gelatin methacrylate (GelMA) matrix doped with hypoxic seeds of GelMA functionalized with a fluorinated oxadiazole (GelOXA), which ensures the delivery of hypoxic cues to human articular chondrocytes (hACs) embedded within the scaffold. We found that the GelMA/GelOXA scaffold preserved hACs viability, maintained their native phenotype, and significantly improved the production of type II collagen. Besides, we observed a reduction in type I and type X collagen, characteristic of unhealthy cartilage. These findings pave the way for the regeneration of healthy, hyaline-like cartilage, by delivering hypoxic cues even under normoxic conditions. Furthermore, the GelMA/GelOXA scaffolds ability to deliver healing signals directly to the injury site holds great potential for treating OA and related CDs, and has the potential to revolutionize the field of cartilage repair and regenerative medicine.

bioengineering↗