Correction: Piola et al. 3D Bioprinting of Gelatin-Xanthan Gum Composite Hydrogels for Growth of Human Skin Cells. Int. J. Mol. Sci. 2022, 23, 539.

In the original publication [...].

Clodronate Reduces ATP-Containing Microvesicle Releasing Induced by Nociceptive Stimuli in Human Keratinocytes.

Clodronate (Clod), a first-generation bisphosphonate, acts as a natural analgesic inhibiting vesicular storage of the nociception mediator ATP by vesicular nucleotide transporter (VNUT). Epidermal keratinocytes participate in cutaneous nociception, accumulating ATP within vesicles, which are released following different stimulations. Under stress conditions, keratinocytes produce microvesicles (MVs) by shedding from plasma membrane evagination. MV secretion has been identified as a novel and universal mode of intercellular communication between cells. The aim of this project was to evaluate if two nociceptive stimuli, Capsaicin and Potassium Hydroxide (KOH), could stimulate MV shedding from human keratinocytes, if these MVs could contain ATP, and if Clod could inhibit this phenomenon. In our cellular model, the HaCaT keratinocyte monolayer, both Capsaicin and KOH stimulated MV release after 3 h incubation, and the released MVs contained ATP. Moreover, Clod (5 µM) was able to reduce Caps-induced MV release and abolish the one KOH induced, while the Dansylcadaverine, an endocytosis inhibitor of Clod uptake, partially failed to block the bisphosphonate activity. Based on these new data and given the role of the activation of ATP release by keratinocytes as a vehicle for nociception and pain, the "old" bisphosphonate Clodronate could provide the pharmacological basis to develop new local analgesic drugs.

Skeletal maturation evaluation: which is the reliability of dental calcification Demirjian method versus hand-wrist X-ray in growing subjects? A systematic review.

OBJECTIVES: This systematic review aimed at evaluating the reliability of dental maturation (DM) according to Demirjian method compared to hand and wrist maturation (HWM) to assess skeletal maturity (SM) in growing subjects, to identify the teeth and the corresponding mineralisation stages related to the pubertal growth spurt (PGS). MATERIALS AND METHODS: PubMed, Scopus, and Web of Science were systematically searched until January 5th, 2024, to identify observational cross-sectional studies that assessed the reliability of Demirjian method compared to the HWM methods (i.e., Grave and Brown and Fishman) in growing subjects. The quality assessment was evaluated using the Joanna Briggs Institute (JBI) Critical Appraisal Checklist. RESULTS: Out of 136 papers suitable for title/abstract screening, 19 included studies. Of them, 17 papers showed the reliability of Demirjian DM method compared to HWM Fishman and Grave and Brown methods to assess SM in growing subjects. According to JBI Critical Appraisal Checklist, 12 papers were high-quality studies and 7 papers were medium-quality studies.  Conclusions: The mandibular second molar might be considered as the best indicator compared to other teeth and that the peak of growth occurs no earlier than stage F in females and stage G in males according to Demirjian method. Also, the mandibular canine might be analysed as indicator of SM in males, and results suggest that the peak of growth occurs no earlier than maturation stage F according to Demirjian method, only in male subjects. Further studies are needed to confirm these findings.

Polydopamine Blending Increases Human Cell Proliferation in Gelatin-Xanthan Gum 3D-Printed Hydrogel.

BACKGROUND: Gelatin-xanthan gum (Gel-Xnt) hydrogel has been previously modified to improve its printability; now, to increase its ability for use as cell-laden 3D scaffolds (bioink), polydopamine (PDA), a biocompatible, antibacterial, adhesive, and antioxidant mussel-inspired biopolymer, has been added (1-3% v/v) to hydrogel. METHODS: Control (CT) and PDA-blended hydrogels were used to print 1 cm2 grids. The hydrogels' printability, moisture, swelling, hydrolysis, and porosity were tested after glutaraldehyde (GTA) crosslinking, while biocompatibility was tested using primary human-derived skin fibroblasts and spontaneously immortalized human keratinocytes (HaCaT). Keratinocyte or fibroblast suspension (100 µL, 2.5 × 105 cells) was combined with an uncrosslinked CT and PDA blended hydrogel to fabricate cylinders (0.5 cm high, 1 cm wide). These cylinders were then cross-linked and incubated for 1, 3, 7, 14, and 21 days. The presence of cells within various hydrogels was assessed using optical microscopy. RESULTS AND DISCUSSION: PDA blending did not modify the hydrogel printability or physiochemical characteristics, suggesting that PDA did not interfere with GTA crosslinking. On the other hand, PDA presence strongly accelerated and increased both fibroblast and keratinocyte growth inside. This effect seemed to be linked to the adhesive abilities of PDA, which improve cell adhesion and, in turn, proliferation. CONCLUSIONS: The simple PDA blending method described could help in obtaining a new bioink for the development of innovative 3D-printed wound dressings.

Laser Biostimulation Induces Wound Healing-Promoter ß2-Defensin Expression in Human Keratinocytes via Oxidative Stress.

The innate immune system is the first line of defense of the body composed of anatomical barriers, such as skin and mucosa, as well as effector cells, antimicrobial peptides, soluble mediators, and cell receptors able to detect and destroy viruses and bacteria and to sense trauma and wounds to initiate repair. The human ß-defensins belong to a family of antimicrobial small cationic peptides produced by epithelial cells, and show immunomodulatory and pro-healing activities. Laser biostimulation is a therapy widely used to contrast microbial infection and to accelerate wound healing through biological mechanisms that include the creation of oxidative stress. In this paper, we explored laser biostimulation's ability to modulate the production of two ß-defensins, hBD-1 and hBD-2, in human keratinocytes and whether this modulation was, at least in part, oxidative-stress-dependent. Human spontaneously immortalized keratinocytes (HaCaT) were stimulated using laser irradiation at a 980 nm wavelength, setting the power output to 1 W (649.35 mW/cm2) in the continuous mode. Cells were irradiated for 0 (negative control), 5, 10, 25 and 50 s, corresponding to an energy stimulation of 0, 5, 10, 25 and 50 J. Positive control cells were treated with lipopolysaccharide (LPS, 200 ng/mL). After 6 and 24 h of treatment, the cell conditioned medium was collected and analyzed via ELISA assay for the production of hBD-1 and hBD-2. In another set of experiments, HaCaT were pre-incubated for 45 min with antioxidant drugs-vitamin C (Vit. C, 100 µM), sodium azide (NaN3, 1 mM); ω-nitro-L-arginine methyl ester (L-NAME, 10 mM) and sodium pyruvate (NaPyr, 100 µM)-and then biostimulated for 0 or 50 s. After 6 h, the conditioned medium was collected and used for the ELISA analysis. The hBD-1 and hBD-2 production by HaCaT was significantly increased by single laser biostimulation after 6 h in an energy-dependent fashion compared to basal levels, and both reached production levels induced by LPS. After 24 h, only hBD-2 production induced by laser biostimulation was further increased, while the basal and stimulated hBD-1 levels were comparable. Pre-incubation with antioxidative drugs was able to completely abrogate the laser-induced production of both hBD-1 and hBD-2 after 6 h, with the exception of hBD-1 production in samples stimulated after NaN3 pre-incubation. A single laser biostimulation induced the oxidative-stress-dependent production of both hBD-1 and hBD-2 in human keratinocytes. In particular, the pro-healing hBD-2 level was almost three times higher than the baseline level and lasted for 24 h. These findings increase our knowledge about the positive effects of laser biostimulation on wound healing.

Oral-Gut Microbiota, Periodontal Diseases, and Arthritis: Literature Overview on the Role of Probiotics.

Periodontal diseases are oral inflammatory diseases affecting the tissues supporting and surrounding the teeth and include gingivitis and periodontitis. Oral pathogens may lead to microbial products spreading into the systemic circulation and reaching distant organs, while periodontal diseases have been related to low-grade systemic inflammation. Gut and oral microbiota alterations might play a role in the pathogenesis of several autoimmune and inflammatory diseases including arthritis, considering the role of the gut-joint axis in the regulation of molecular pathways involved in the pathogenesis of these conditions. In this scenario, it is hypothesized that probiotics might contribute to the oral and intestinal micro-ecological balance and could reduce low-grade inflammation typical of periodontal diseases and arthritis. This literature overview aims to summarize state-of-the-art ideas about linkages among oral-gut microbiota, periodontal diseases, and arthritis, while investigating the role of probiotics as a potential therapeutic intervention for the management of both oral diseases and musculoskeletal disorders.

Breaking a Vicious Circle: Lymphangiogenesis as a New Therapeutic Target in Wound Healing.

The lymphatic system is of fundamental importance in maintaining a fluid balance in the body and tissue homeostasis; it drains protein-rich lymph from the interstitial space and facilitates the release of cells that mediate the immune response. When one tissue is damaged, more cells and tissues work to repair the damaged site. Blood and lymph vessels are particularly important for tissue regeneration and healing. Angiogenesis is the process of the formation of new blood vessels and is induced by angiogenic factors such as VEGF-A; VEGF-C/D-induced lymphangiogenesis and both occur simultaneously during wound healing. After the inflammatory phase, lymphatic vessels suppress inflammation by aiding in the drainage of inflammatory mediators; thus, disorders of the lymphatic system often result in chronic and disabling conditions. It has recently been clarified that delayed wound healing, as in diabetes, can occur as a consequence of impaired lymphangiogenesis. In this review, we have highlighted recent advances in understanding the biology underlying lymphangiogenesis and its key role in wound healing, and the possibility of its pharmacological modulation as a novel therapeutic strategy for the treatment of chronic wounds.

The Oral Microbiome for Geographic Origin: An Italian Study.

The human oral microbiome has primarily been studied in clinical settings and for medical purposes. More recently, oral microbial research has been incorporated into other areas of study. In forensics, research has aimed to exploit the variation in composition of the oral microbiome to answer forensic relevant topics, such as human identification and geographical provenience. Several studies have focused on the use of microbiome for continental, national, or ethnic origin evaluations. However, it is not clear how the microbiome varies between similar ethnic populations across different regions in a country. We report here a comparison of the oral microbiomes of individuals living in two regions of Italy - Lombardy and Piedmont. Oral samples were obtained by swabbing the donors' oral mucosa, and the V4 region of the 16S rRNA gene was sequenced from the extracted microbial DNA. Additionally, we compared the oral and the skin microbiome from a subset of these individuals, to provide an understanding of which anatomical region may provide more robust results that can be useful for forensic human identification. Initial analysis of the oral microbiota revealed the presence of a core oral microbiome, consisting of nine taxa shared across all oral samples, as well as unique donor characterising taxa in 31 out of 50 samples. We also identified a trend between the abundance of Proteobacteria and Bacteroidota and the smoking habits, and of Spirochaetota and Synergistota and the age of the enrolled participants. Whilst no significant differences were observed in the oral microbial diversity of individuals from Lombardy or Piedmont, we identified two bacterial families - Corynebacteriaceae and Actinomycetaceae - that showed abundance trends between the two regions. Comparative analysis of the skin and oral microbiota showed significant differences in the alpha (p = 0.0011) and beta (Pr(>F)= 9.999e-05) diversities. Analysis of skin and oral samples from the same donor further revealed that the skin microbiome contained more unique donor characterising taxa than the oral one. Overall, this study demonstrates that whilst the oral microbiome of individuals from the same country and of similar ethnicity are largely similar, there may be donor characterising taxa that might be useful for identification purposes. Furthermore, the bacterial signatures associated with certain lifestyles could provide useful information for investigative purposes. Finally, additional studies are required, the skin microbiome may be a better discriminant for human identification than the oral one.

Temporomandibular Disorders and Vitamin D Deficiency: What Is the Linkage between These Conditions? A Systematic Review.

Although a growing body of literature has been emphasizing the role of vitamin D in oral health, there is still a gap of knowledge regarding the correlation between temporomandibular disorders (TMDs) and vitamin D. Therefore, the aim of this systematic review was to assess the linkage between hypovitaminosis D and TMDs to map the current literature in this field. On 10 September 2022, PubMed, Scopus, and Web of Science databases were systematically searched from the date of their inception to identify the studies that had assessed patients with TMDs. The primary outcome assessed in this review was the relationship between hypovitaminosis D and TMDs. Out of the 329 studies identified, 13 studies met the eligibility criteria and were included in the present work. Seven studies assessed the relationship between vitamin D and TMDs, reporting that vitamin D serum levels are lower in patients with TMDs. Our results suggested that vitamin D receptor (VDR) polymorphisms might have a role in TMDs' development. However, the quality assessed underlined that only one study did not present a serious risk of bias. Further good-quality studies are needed to clarify the linkage between vitamin D deficiency and TMDs, but the evidence currently available has suggested potential correlations.

Oral Health in Breast Cancer Women with Vitamin D Deficiency: A Machine Learning Study.

Breast cancer (BC) survivors treated with aromatase inhibitors (AIs) commonly show several pathological issues, including poor oral health, bone health impairment, and vitamin D deficiency. However, to date, oral health issues in BC survivors treated with AIs have been poorly investigated and their relationship with vitamin D deficiency are far from being understood. This study aimed to evaluate the correlation between oral health and vitamin D status in BC survivors undergoing treatment with AIs through a machine learning approach. In this cross-sectional study, we included post-menopausal BC women with vitamin D deficiency undergoing AIs therapy. The outcome measures were the following: oral health indexes as the Decayed, Missing, and Filled Permanent Teeth Index (DMFT); serum levels of 25(OH)D3; Bone Mineral Density (BMD); and the diagnosis of osteoporosis. We included 41 post-menopausal BC women, mean aged 66.10 ± 8.47 years, with mean serum levels of vitamin D of 14.63 ± 6.62 ng/mL. Furthermore, 56.10% of patients had a diagnosis of osteoporosis and 36.59% were osteopenic. DMFT was significantly related to smoking (p-value = 0.005) and dental floss use (p-value = 0.001). There was a significant correlation between DMFT and vitamin D levels (Pearson's r: -0.73; p-value = 0.001). The regression machine learning model showed that vitamin D status and the use of dental floss were the most relevant variables in terms of correlation with DMFT. In conclusion, vitamin D deficiency, inadequate use of dental floss, and smoking had a negative impact on oral health in BC women. Thus, vitamin D deficiency screening and supplementation and a prompt oral rehabilitation plan should be suggested and implemented in the complex treatment framework of BC survivors undergoing treatment with AIs.

Aging hampers neutrophil extracellular traps (NETs) efficacy.

BACKGROUND: NETosis is a neutrophil-mediated defense mechanism during which DNA and enzymes are extruded forming a network (NETs) trapping and killing different pathogens. NETosis is reduced in both mice and humans during aging. AIMS: We explored the difference in the efficacy of NETs released in elderly (> 65 years) versus adults (20-50 years) subjects in inhibiting Staphylococcus aureus growth and activating the growth of keratinocytes. METHODS: Neutrophil granulocytes, obtained from venous blood both in healthy elderly and adult subjects, were stimulated by LPS (0-250 µg/ml) to induce the formation of NET. NETs were quantified by SYBR Green staining and growth inhibition of S. aureus was evaluated by disk diffusion test. Furthermore, NETs (0-500 ng/ml) were added to immortalized human keratinocytes (HaCaT cells), and their proliferation was evaluated by MTT assay after 24 h. Finally, the DNA size of NETs was evaluated by flow cytometry after SYBR Green staining. RESULTS: Greater production of NETs was observed in elderly subjects than in adults, but these NETs showed reduced bactericidal capacity and HaCaT cells' proliferation stimulation. The activities of the NETs are related to the size of the extruded DNA threads, and when NETs size was analyzed, DNA from elderly showed a higher size compared to that obtained by adults. DISCUSSION: Unexpected results showed aging-related NETs structural modification resulting in both a lower antimicrobial activity and keratinocyte proliferation stimulation compared to NETs obtained from adults. CONCLUSIONS: The NETs DNA size observed in elderly subjects has not been previously reported and could be part of other pathogenic mechanisms observed in aging.

ICOSL Stimulation by ICOS-Fc Accelerates Cutaneous Wound Healing In Vivo.

BACKGROUND: ICOS and its ligand ICOSL are immune receptors whose interaction triggers bidirectional signals that modulate the immune response and tissue repair. AIM: The aim of this study was to assess the in vivo effects of ICOSL triggering by ICOS-Fc, a recombinant soluble form of ICOS, on skin wound healing. METHODS: The effect of human ICOS-Fc on wound healing was assessed, in vitro, and, in vivo, by skin wound healing assay using ICOS-/- and ICOSL-/- knockout (KO) mice and NOD-SCID-IL2R null (NSG) mice. RESULTS: We show that, in wild type mice, treatment with ICOS-Fc improves wound healing, promotes angiogenesis, preceded by upregulation of IL-6 and VEGF expression; increases the number of fibroblasts and T cells, whereas it reduces that of neutrophils; and increases the number of M2 vs. M1 macrophages. Fittingly, ICOS-Fc enhanced M2 macrophage migration, while it hampered that of M1 macrophages. ICOS-/- and ICOSL-/- KO, and NSG mice showed delayed wound healing, and treatment with ICOS-Fc improved wound closure in ICOS-/- and NSG mice. CONCLUSION: These data show that the ICOS/ICOSL network cooperates in tissue repair, and that triggering of ICOSL by ICOS-Fc improves cutaneous wound healing by increasing angiogenesis and recruitment of reparative macrophages.

Microbial DNA in human nucleic acid extracts: Recoverability of the microbiome in DNA extracts stored frozen long-term and its potential and ethical implications for forensic investigation.

Human DNA samples can remain unaltered for years and preserve important genetic information for forensic investigations. In fact, besides human genetic information, these extracts potentially contain additional valuable information: microbiome signatures. Forensic microbiology is rapidly becoming a significant tool for estimating post-mortem interval (PMI), and establishing cause of death and personal identity. To date, the possibility to recover unaltered microbiome signatures from human DNA extracts has not been proven. This study examines the microbiome signatures within human DNA extracts obtained from six cadavers with different PMIs, which were stored frozen for 5-16 years. Results demonstrated that the microbiome can be co-extracted with human DNA using forensic kits designed to extract the human host's DNA from different tissues and fluids during decomposition. We compared the microbial communities identified in these samples with microbial DNA recovered from two human cadavers donated to the Forensic Anthropology Center at Texas State University (FACTS) during multiple decomposition stages, to examine whether the microbial signatures recovered from "old" (up to 16 years) extracts are consistent with those identified in recently extracted microbial DNA samples. The V4 region of 16 S rRNA gene was amplified and sequenced using Illumina MiSeq for all DNA extracts. The results obtained from the human DNA extracts were compared with each other and with the microbial DNA from the FACTS samples. Overall, we found that the presence of specific microbial taxa depends on the decomposition stage, the type of tissue, and the depositional environment. We found no indications of contamination in the microbial signatures, or any alterations attributable to the long-term frozen storage of the extracts, demonstrating that older human DNA extracts are a reliable source of such microbial signatures. No shared Core Microbiome (CM) was identified amongst the total 18 samples, but we identified certain species in association with the different decomposition stages, offering potential for the use of microbial signatures co-extracted with human DNA samples for PMI estimation in future. Unveiling the new significance of older human DNA extracts brings with it important ethical-legal considerations. Currently, there are no shared legal frameworks governing the long-term storage and use of human DNA extracts obtained from crime scene evidence for additional research purposes. It is therefore important to create common protocols on the storage of biological material collected at crime scenes. We review existing legislation and guidelines, and identify some important limitations for the further development and application of forensic microbiomics.

3D Bioprinting of Gelatin-Xanthan Gum Composite Hydrogels for Growth of Human Skin Cells.

In recent years, bioprinting has attracted much attention as a potential tool for generating complex 3D biological constructs capable of mimicking the native tissue microenvironment and promoting physiologically relevant cell-cell and cell-matrix interactions. The aim of the present study was to develop a crosslinked 3D printable hydrogel based on biocompatible natural polymers, gelatin and xanthan gum at different percentages to be used both as a scaffold for cell growth and as a wound dressing. The CellInk Inkredible 3D printer was used for the 3D printing of hydrogels, and a glutaraldehyde solution was tested for the crosslinking process. We were able to obtain two kinds of printable hydrogels with different porosity, swelling and degradation time. Subsequently, the printed hydrogels were characterized from the point of view of biocompatibility. Our results showed that gelatin/xanthan-gum bioprinted hydrogels were biocompatible materials, as they allowed both human keratinocyte and fibroblast in vitro growth for 14 days. These two bioprintable hydrogels could be also used as a helpful dressing material.

Photobiomodulation induces microvesicle release in human keratinocytes: PI3 kinase-dependent pathway role.

Microvesicles (MVs, 100-1000 nm diameter) are released into the extracellular environment by mammalian cells. MVs interact with near or remote cells through different mechanisms; in particular, MVs from human keratinocytes accelerate wound healing. Photobiomodulation by laser improves wound healing, but no information is available about its effects on MV release from human keratinocyte. Human-immortalized keratinocytes (human adult low-calcium high-temperature, HaCaT) were starved for 24 h and then irradiated using a 980-nm energy density of 0, 16.2, 32.5, and 48.7 J/cm2. After 24 h, MVs released in the conditioned medium were isolated, stained, and quantified using flow cytometry. MVs were distinguished from exosomes on the basis of their volume (forward scatter signals). In some experiments, phosphatidylinositol 3-kinase (PI-3K) activity, involved in MV release and stimulated by laser light, was inhibited by pre-treating cells with Wortmannin (WRT, 10 µg/mL). MVs were observed in HaCaT-conditioned medium both in basal- and laser-stimulated conditions. Photobiomodulation therapy, also known as PBMT, was able to increase MV release from human keratinocytes reaching a maximum effect at 32.5 J/cm2 with a stimulation of (148.6 ±15.1)% of basal (p<0.001). PI-3K activity inhibition strongly reduced both basal- and laser-induced MV release; but PBMT by laser still increased MV release, compared to basal values in the presence of WRT. In vitro near infrared photobiomodulation increased the releasing of MVs from human keratinocytes, while Wortmannin, a PI-3K inhibitor, negatively affects both basal- and laser-induced releasing. Laser-induced MV release could be a new effect of biostimulation on the wound healing process.

Verteporfin-Loaded Mesoporous Silica Nanoparticles' Topical Applications Inhibit Mouse Melanoma Lymphangiogenesis and Micrometastasis In Vivo.

Photodynamic therapy (PDT) has been pointed out as a candidate for improving melanoma treatment. Nanotechnology application in PDT has increased its efficacy by reducing side effects. Herein, mesoporous silica nanoparticles (MSNs) conjugated with verteporfin (Ver-MSNs), in use with PDT, were administered in mice to evaluate their efficacy on lymphoangiogenesis and micrometastasis in melanoma. Melanoma was induced in mice by the subcutaneous injection of B16-F10 cells. The mice were transcutaneously treated with MSNs, Ver-MSNs, or glycerol and exposed to red light. The treatment was carried out four times until day 20. Lymphangiogenesis and micrometastasis were identified by the immunohistochemical method. Lymphoangiogenesis was halved by MSN treatment compared with the control animals, whereas the Ver-MSN treatment almost abolished it. A similar reduction was also observed in lung micrometastasis. PDT with topically administrated Ver-MSNs reduced melanoma lymphoangiogenesis and lung micrometastasis, as well as tumor mass and angiogenesis, and therefore their use could be an innovative and useful tool in melanoma clinical therapy.

"Touch microbiome" as a potential tool for forensic investigation: A pilot study.

Human skin hosts a variety of microbes that can be transferred to surfaces ("touch microbiome"). These microorganisms can be considered as forensic markers similarly to "touch DNA". With this pilot study, we wanted to evaluate the transferability and persistence of the "touch microbiome" on a surface after the deposition of a fingerprint and its exposure for 30 days at room temperature. Eleven volunteers were enrolled in the study. Skin microbiome samples were collected by swabbing the palm of their hands; additionally, donors were asked to touch a glass microscope slide to deposit their fingerprints, that were then swabbed. Both human and microbial DNA was isolated and quantified. Amelogenin locus and 16 human STRs were amplified, whereas the V4 region of 16 S rRNA gene was sequenced using Illumina MiSeq platform. STR profiles were successfully typed for 5 out of 22 "touch DNA" samples, while a microbiome profile was obtained for 20 out of 22 "touch microbiome" samples. Six skin core microbiome taxa were identified, as well as unique donor characterizing taxa. These unique taxa may have relevance for personal identification studies and may be useful to provide forensic intelligence information also when "touch DNA" fails. Additional future studies including greater datasets, additional time points and a greater number of surfaces may clarify the applicability of "touch microbiome" studies to real forensic contexts.

NETosis in Wound Healing: When Enough Is Enough.

The neutrophils extracellular traps (NETs) are a meshwork of chromatin, histonic and non-histonic proteins, and microbicidal agents spread outside the cell by a series of nuclear and cytoplasmic events, collectively called NETosis. NETosis, initially only considered a defensive/apoptotic mechanism, is now considered an extreme defensive solution, which in particular situations induces strong negative effects on tissue physiology, causing or exacerbating pathologies as recently shown in NETs-mediated organ damage in COVID-19 patients. The positive effects of NETs on wound healing have been linked to their antimicrobial activity, while the negative effects appear to be more common in a plethora of pathological conditions (such as diabetes) and linked to a NETosis upregulation. Recent evidence suggests there are other positive physiological NETs effects on wound healing that are worthy of a broader research effort.

Bone Muscle Crosstalk in Spinal Cord Injuries: Pathophysiology and Implications for Patients' Quality of Life.

PURPOSE OF REVIEW: The goal of this review is to provide a comprehensive overview of (i) bone and muscle tissue modifications pathophysiology in spinal cord injury (SCI), (ii) experimental data on the physiopathological mechanisms underpinning these modifications and their similarities with the aging process, and (iii) potential clinical implications in the management of the disabling sequelae of SCI. RECENT FINDINGS: Several studies attempted to describe the biology underpinning the links between bone and muscle tissues in the setting of highly disabling conditions, such as osteoporosis, sarcopenia, and neurodegenerative disorders, although these bidirectional connections remain still unclear. SCI could be considered an in vivo paradigmatic model of the bone muscle interactions in unloading conditions that might be expanded in the field of neurodegenerative disorders or cancer studies. Future studies should take into consideration the newer insights into bone muscle crosstalk in order to develop multitargeted and therapeutic interventions.

Spinal Cord Injury as a Model of Bone-Muscle Interactions: Therapeutic Implications From in vitro and in vivo Studies.

Spinal cord injuries (SCIs) represent a variety of conditions related to the damage of the spinal cord with consequent musculoskeletal repercussions. The bone and muscle tissues share several catabolic pathways that lead to variable degrees of disability in SCI patients. In this review article, we provide a comprehensive characterization of the available treatment options targeting the skeleton and the bone in the setting of SCI. Among the pharmacological intervention, bisphosphonates, anti-sclerostin monoclonal antibodies, hydrogen sulfide, parathyroid hormone, and RANKL pathway inhibitors represent valuable options for treating bone alterations. Loss phenomena at the level of the muscle can be counteracted with testosterone, anabolic-androgenic steroids, and selective androgen receptor modulators. Exercise and physical therapy are valuable strategies to increase bone and muscle mass. Nutritional interventions could enhance SCI treatment, particularly in the setting of synergistic and multidisciplinary interventions, but there are no specific guidelines available to date. The development of multidisciplinary recommendations is required for a proper clinical management of SCI patients.