Gelatin Methacrylic Acid Hydrogel-Based Nerve Growth Factors Enhances Neural Stem Cell Growth and Differentiation to Promote Repair of Spinal Cord Injury.

Background: The challenge in treating irreversible nerve tissue damage has resulted in suboptimal outcomes for spinal cord injuries (SCI), underscoring the critical need for innovative treatment strategies to offer hope to patients. Methods: In this study, gelatin methacrylic acid hydrogel scaffolds loaded with nerve growth factors (GMNF) were prepared and used to verify the performance of SCI. The physicochemical and biological properties of the GMNF were tested. The effect of GMNF on activity of neuronal progenitor cells (NPCs) was investigated in vitro. Histological staining and motor ability was carried out to assess the ability of SCI repair in SCI animal models. Results: Achieving nerve growth factors sustained release, GMNF had good biocompatibility and could effectively penetrate into the cells with good targeting permeability. GMNF could better enhance the activity of NPCs and promote their directional differentiation into mature neuronal cells in vitro, which could exert a good neural repair function. In vivo, SCI mice treated with GMNF recovered their motor abilities more effectively and showed better wound healing by macroscopic observation of the coronal surface of their SCI area. Meanwhile, the immunohistochemistry demonstrated that the GMNF scaffolds effectively promoted SCI repair by better promoting the colonization and proliferation of neural stem cells (NSCs) in the SCI region and targeted differentiation into mature neurons. Conclusion: The application of GMNF composite scaffolds shows great potential in SCI treatment, which are anticipated to be a potential therapeutic bioactive material for clinical application in repairing SCI in the future.

Influence of free and microencapsulated recombinant rabbit nerve growth factor with chitosan on rabbit sperm quality parameters.

ß-nerve growth factor (ßNGF) plays a crucial role in reproductive physiology and sperm quality. Enzymatic activity of seminal plasma and vaginal fluids reduces available ßNGF and it has been demonstrated that chitosan microspheres could protect rrßNGF from degradation. This study examined the effects of microencapsulated rrbNGF with chitosan on rabbit sperm viability, motility and capacitation status. Results showed that 0.5 and 1 µg/mL of microencapsulated rrßNGF, as well as free rrßNGF or empty microspheres, did not adversely affect sperm viability or total motility after 2 h of incubation. However, the highest progressivity kinetic parameters were observed with 1 µg/mL free rrßNGF, while the highest curvilinear velocity (VCL) occurred with 0.5 µg/mL microencapsulated rrßNGF. Empty chitosan microspheres did not induce acrosome reaction (AR), but both concentrations of free and rrßNGFch favoured AR during in vitro incubation. The study suggests that using chitosan spheres did not show any adverse effects on sperm traits, unlike free rßNGF and rrßNGFch promoted capacitation and AR. Further research is needed to explore the potential of rrßNGFch in modifying in vitro capacitation and inducing ovulation during artificial insemination.

Intranasal human-recombinant nerve growth factor administration improves cognitive functions in a child with severe traumatic brain injury.

BACKGROUND: Behavioral and neuropsychological functions are frequent long-term sequelae of severe traumatic brain injury (TBI). Neuropeptides, such as nerve growth factor (NGF), can enhance neurogenesis and improve cognitive functions after TBI, playing a pivotal role in neuroplasticity. A limited number of studies documented the safety and efficacy of intranasal NGF administration in children with severe TBI. CASE REPORT: A fourteen-year-old boy with a diffuse axonal injury secondary to severe TBI was treated with human-recombinant NGF administration. This patient underwent treatment with intranasal hr-NGF administration at a total dose of 50 gamma/kg, three times a day for seven consecutive days. The treatment schedule was performed for 4 cycles, at one month distance each. NGF administration improved radiologic functional assessment evaluated with positron emission tomography scan (PET) and single photon emission computed tomography (SPECT), with an important improvement in clinical conditions. Significant improvements were also observed, mainly in cognitive processes, memory, the planning of a communication strategy, execution skills, attention, and verbal expression. No side effects were reported. CONCLUSIONS: Additional studies are required to gain a deeper insight into this neurotrophin's neuroprotective function, but our findings reveal a potential efficacy of intranasal hr-NGF administration in enhancing cognitive and clinical outcomes among children with diffuse axonal injury after severe TBI.

Growth Factor Gene Therapy for Alzheimer's Disease.

Nervous system growth factors are natural proteins of the brain that influence neuronal survival and function throughout life, from embryonic development to old age. In animal models of Alzheimer's disease (AD), the growth factor brain derived neurotrophic factor (BDNF) prevents neuronal death, activates neuronal function, builds new synapses and improves learning and memory. Accordingly, we are determining whether gene delivery of BDNF in patients with AD will slow disease progression and improve memory. In a previous clinical trial of nerve growth factor (NGF) gene therapy in AD patients (NCT00017940, June 2001), we learned that growth factors can unequivocally elicit classic trophic responses from degenerating neurons in AD. Experience gained from the earlier NGF gene therapy trial is guiding our effort to optimize gene delivery of BDNF in our present clinical program (NCT05040217, June 2021).

Siah3 acts as a physiological mitophagy suppressor that facilitates axonal degeneration.

Mitophagy eliminates dysfunctional mitochondria, and defects in this cellular housekeeping mechanism are implicated in various age-related diseases. Here, we found that mitophagy suppression by the protein Siah3 promoted developmental axonal remodeling in mice. Siah3-deficient mice displayed increased peripheral sensory innervation. Cultured Siah3-deficient sensory neurons exhibited delays in both axonal degeneration and caspase-3 activation in response to withdrawal of nerve growth factor. Mechanistically, Siah3 was transcriptionally induced by the loss of trophic support and formed a complex with the cytosolic E3 ubiquitin ligase parkin, a core component of mitophagy, in transfected cells. Axons of Siah3-deficient neurons mounted profound mitophagy upon initiation of degeneration but not under basal conditions. Neurons lacking both Siah3 and parkin did not exhibit the delay in trophic deprivation-induced axonal degeneration or the induction of axonal mitophagy that was seen in Siah3-deficient neurons. Our findings reveal that mitophagy regulation acts as a gatekeeper of a physiological axon elimination program.

Astragaloside IV confronts amyloid-beta-induced astrocyte senescence via hsp90aa1.

Cell senescence is intensively related to aging and neurodegenerative diseases. This study aimed to explore the effect and targets of Astragaloside IV against amyloid-beta-induced astrocyte senescence. Oligomerized amyloid-beta was prepared to culture with human astrocytes. The effects of Astragaloside IV were assessed based on SA-ß-gal staining analysis, senescence markers (p53, p16INK4, and p21WAF1), neurotrophic growth factor levels (qRT-PCR), and cell proliferation (CCK-8 kit). The targets for Astragaloside IV were predicted, and hsp90aa1 protein was verified using molecular docking. After hsp90aa1 overexpression, the effects of Astragaloside IV on amyloid-beta-induced astrocytes were assessed. Treatment of human amyloid-beta-induced astrocytes with Astragaloside IV can decrease the percentage of SA-ß-gal positive cells, downregulate the p53, p16INK4, and p21WAF1 levels, and increase the levels of neurotrophic growth factors (IGF-1 and NGF mRNA) and cell proliferation. Based on target prediction, hsp90aa1 was found to be a potential target of Astragaloside IV. Moreover, cellular experiments demonstrated that exogenously enhanced expression of hsp90aa1 overexpression suppressed the protective effect of Astragaloside IV on amyloid-beta-induced human astrocytes. The results presented here demonstrate that Astragaloside IV could confront amyloid-beta-induced astrocyte senescence via hsp90aa1, possibly opening new therapeutic avenues.

Heterogeneous enhancer states orchestrate ß cell responses to metabolic stress.

Obesity-induced ß cell dysfunction contributes to the onset of type 2 diabetes. Nevertheless, elucidating epigenetic mechanisms underlying islet dysfunction at single cell level remains challenging. Here we profile single-nuclei RNA along with enhancer marks H3K4me1 or H3K27ac in islets from lean or obese mice. Our study identifies distinct gene signatures and enhancer states correlating with ß cell dysfunction trajectory. Intriguingly, while many metabolic stress-induced genes exhibit concordant changes in both H3K4me1 and H3K27ac at their enhancers, expression changes of specific subsets are solely attributable to either H3K4me1 or H3K27ac dynamics. Remarkably, a subset of H3K4me1+H3K27ac- primed enhancers prevalent in lean ß cells and occupied by FoxA2 are largely absent after metabolic stress. Lastly, cell-cell communication analysis identified the nerve growth factor (NGF) as protective paracrine signaling for ß cells through repressing ER stress. In summary, our findings define the heterogeneous enhancer responses to metabolic challenges in individual ß cells.

Effects of mesenchymal stromal cells and human recombinant Nerve Growth Factor delivered by bioengineered human corneal lenticule on an innovative model of diabetic retinopathy.

Introduction: Diabetic retinopathy (DR) is a microvascular complication of diabetes in which neurodegeneration has been recently identified as a driving force. In the last years, mesenchymal stromal cells (MSCs) and neurotrophins like Nerve Growth Factor (NGF), have garnered significant attention as innovative therapeutic approaches targeting DR-associated neurodegeneration. However, delivering neurotrophic factors directly in the eye remains a challenge. Hence, this study evaluated the effects of MSCs from human amniotic fluids (hAFSCs) and recombinant human NGF (rhNGF) delivered by human corneal lenticule (hCL) on a high glucose (HG) induced ex vivo model simulating the molecular mechanisms driving DR. Methods: Porcine neuroretinal explants exposed to HG (25 mM for four days) were used to mimic DR ex vivo. hCLs collected from donors undergoing refractive surgery were decellularized using 0.1% sodium dodecyl sulfate and then bioengineered with hAFSCs, microparticles loaded with rhNGF (rhNGF-PLGA-MPs), or both simultaneously. Immunofluorescence (IF) and scanning electron microscopy (SEM) analyses were performed to confirm the hCLs bioengineering process. To assess the effects of hAFSCs and rhNGF, bioengineered hCLs were co-cultured with HG-treated neuroretinal explants and following four days RT-PCR and cytokine array experiments for inflammatory, oxidative, apoptotic, angiogenic and retinal cells markers were performed. Results: Data revealed that HG-treated neuroretinal explants exhibit a characteristic DR-phenotype, including increased level of NF-kB, NOS2, NRF2 GFAP, VEGFA, Bax/Bcl2 ratio and decreased expression of TUBB3 and Rho. Then, the feasibility to bioengineer decellularized hCLs with hAFSCs and rhNGF was demonstrated. Interestingly, co-culturing hAFSCs- and rhNGF- bioengineered hCLs with HG-treated neuroretinal explants for four days significantly reduced the expression of inflammatory, oxidative, apoptotic, angiogenic and increased retinal markers. Conclusion: Overall, we found for the first time that hAFSCs and rhNGF were able to modulate the molecular mechanisms involved in DR and that bioengineered hCLs represents a promising ocular drug delivery system of hAFSCs and rhNGF for eye diseases treatment. In addition, results demonstrated that porcine neuroretinal explants treated with HG is a useful model to reproduce ex vivo the DR pathophysiology.

Interleukin-1 Beta (IL1B) and Nerve Growth Factor (NGF): Key Players in Rabbit Reproductive Regulation.

Several seminal plasma components, besides NGF, are implicated as ovulation-inducing factors in mammals. This study investigated the IL1B and its receptor IL1R1 in the testis (T), male accessory glands, prostate (P) and seminal vesicles (SV), and uterus (U) of adult rabbits using immunohistochemistry (IHC) and quantitative reverse transcription PCR (RT-qPCR). We also assessed the presence of IL1B in seminal plasma through Western blotting (WB) and examined the interaction between IL1B and NGF in vitro by measuring their production with enzyme-linked immunosorbent assay (ELISA) in the presence of NGF and IL1B alone or with their respective receptor antagonists. IHC revealed IL1B system expression in all reproductive organs studied, with IL1B and IL1R1 localized to the germinative epithelium of the T and the epithelial cells of the accessory glands and U. IL1B gene transcript levels were significantly higher (p < 0.01) in the P and SV compared to the T, while IL1R1 levels were significantly higher (p < 0.001) in the P compared to the other tissues, while IL1R1 levels were three times higher (p < 0.001) in the P. WB confirmed the presence of IL1B in seminal plasma with a 30-35 kDa band. The in vitro study demonstrated that IL1B increased (p < 0.05) basal NGF production in the U, whereas NGF had no effect on IL1B production. These findings provide evidence of the expression of the IL1B/IL1R1 system in both male and female rabbit reproductive tracts and suggest that IL1B in seminal plasma may influence uterine endocrine activity. The results propose a potential role for IL1B in ovulation, in conjunction with NGF, supporting that ovulation may involve inflammatory-like processes.

Bovine Lactoferrin Promotes Neurite Outgrowth in PC12 Cells via the TrkA Receptor.

Lactoferrin (LF) is a multifunctional protein abundant in breast milk that modulates the functions of neural stem cells. Recent studies have demonstrated the efficacy of bovine LF (bLF) in mitigating behavioral changes; however, the molecular mechanisms on the nervous system have not yet been elucidated. The presented study aimed to characterize the molecular mechanisms of bLF on nerve extension in PC12 cells. PC12 cells were treated with 0.01-1000 µg/mL of bLF, and cell viability was determined using the cell counting kit-8 assay after treatment for 24 h. Morphometric evaluation was performed after 24 or 72 h of treatment with 50 ng/mL nerve growth factor (NGF) or 100-500 µg/mL bLF. The molecular mechanisms were investigated using Western blotting and real-time quantitative PCR. Cell viability was significantly decreased after treatment with 600-1000 µg/mL bLF for 24 h compared with the control group. Morphometric evaluation revealed neurite outgrowth after 72 h of NGF treatment, with a significant increase in neurite outgrowth after treatment with 250 µg/mL bLF. The phosphorylated p44/42 expression ratio peaked at 5 min and persisted for up to 10 min. Quantitative real-time PCR revealed a significant decrease in MAP2 expression. Our findings suggested that bLF enhanced PC12 cell neurite outgrowth to a similar extent as NGF. These effects are thought to be mediated via the TrkA receptor and activated by the phosphorylated ERK signaling pathway. Therefore, this study demonstrates that bLF promotes neurite outgrowth via a pathway similar to that of NGF.

[Research progress of silk-based biomaterials for peripheral nerve regeneration].

Objective: To describe the research progress of silk-based biomaterials in peripheral nerve repair and provide useful ideals to accelerate the regeneration of large-size peripheral nerve injury. Methods: The relative documents about silk-based biomaterials used in peripheral nerve regeneration were reviewed and the different strategies that could accelerate peripheral nerve regeneration through building bioactive microenvironment with silk fibroin were discussed. Results: Many silk fibroin tissue engineered nerve conduits have been developed to provide multiple biomimetic microstructures, and different microstructures have different mechanisms of promoting nerve repair. Biomimetic porous structures favor the nutrient exchange at wound sites and inhibit the invasion of scar tissue. The aligned structures can induce the directional growth of nerve tissue, while the multiple channels promote the axon elongation. When the fillers are introduced to the conduits, better growth, migration, and differentiation of nerve cells can be achieved. Besides biomimetic structures, different nerve growth factors and bioactive drugs can be loaded on silk carriers and released slowly at nerve wounds, providing suitable biochemical cues. Both the biomimetic structures and the loaded bioactive ingredients optimize the niches of peripheral nerves, resulting in quicker and better nerve repair. With silk biomaterials as a platform, fusing multiple ways to achieve the multidimensional regulation of nerve microenvironments is becoming a critical strategy in repairing large-size peripheral nerve injury. Conclusion: Silk-based biomaterials are useful platforms to achieve the design of biomimetic hierarchical microstructures and the co-loading of various bioactive ingredients. Silk fibroin nerve conduits provide suitable microenvironment to accelerate functional recovery of peripheral nerves. Different optimizing strategies are available for silk fibroin biomaterials to favor the nerve regeneration, which would satisfy the needs of various nerve tissue repair. Bioactive silk conduits have promising future in large-size peripheral nerve regeneration.

ProNGF elicits retrograde axonal degeneration of basal forebrain neurons through p75NTR and induction of amyloid precursor protein.

Basal forebrain cholinergic neurons (BFCNs) extend long projections to multiple regions in the brain to regulate cognitive functions. Degeneration of BFCNs is seen with aging, after brain injury, and in neurodegenerative disorders. An increase in the amount of the immature proform of nerve growth factor (proNGF) in the cerebral cortex results in retrograde degeneration of BFCNs through activation of proNGF receptor p75NTR. Here, we investigated the signaling cascades initiated at the axon terminal that mediate proNGF-induced retrograde degeneration. We found that local axonal protein synthesis and retrograde transport mediated proNGF-induced degeneration initiated from the axon terminal. Analysis of the nascent axonal proteome revealed that proNGF stimulation of axonal terminals triggered the synthesis of numerous proteins within the axon, and pathway analysis showed that amyloid precursor protein (APP) was a key upstream regulator in cultured BFCNs and in mice. Our findings reveal a functional role for APP in mediating BFCN axonal degeneration and cell death induced by proNGF.

IGF-1 and Glucocorticoid Receptors Are Potential Target Proteins for the NGF-Mimic Effect of ß-Cyclocitral from Lavandula angustifolia Mill. in PC12 Cells.

In the present study, the PC12 cells as a bioassay system were used to screen the small molecules with nerve growth factor (NGF)- mimic effect from Lavandula angustifolia Mill. The ß-Cyclocitral (ß-cyc) as an active compound was discovered, and its chemical structure was also determined. Furthermore, we focused on the bioactive and action mechanism of this compound to do an intensive study with specific protein inhibitors and Western blotting analysis. The ß-cyc had novel NGF-mimic and NGF-enhancer effects on PC12 cells, while the insulin-like growth factor-1 receptor (IGF-1R)/phosphatidylinositol 3 kinase, (PI3K)/serine/threonine-protein kinase (AKT), and glucocorticoid receptor (GR)/phospholipase C (PLC)/protein kinase C (PKC) signaling pathways were involved in the bioactivity of ß-cyc. In addition, the important role of the rat sarcoma (Ras)/protooncogene serine-threonine protein kinase (Raf) signaling pathway was observed, although it was independent of tyrosine kinase (Trk) receptors. Moreover, the non-label target protein discovery techniques, such as the cellular thermal shift assay (CETSA) and drug affinity responsive target stability (DARTS), were utilized to make predictions of its target protein. The stability of IGF-R and GR, proteins for temperature and protease, was dose-dependently increased after treatment of ß-cyc compared with control groups, respectively. These findings indicated that ß-cyc promoted the neuron differentiation of PC12 cells via targeting IGF-1R and GR and modification of downstream signaling pathways.

Discussion of spinal cord neurons apoptosis and neuroprotection mechanism of NGF gene transfection mediated by recombinant adenovirus in EAE mice.

To investigate the spinal cord neuron apoptosis and neuroprotective mechanism of nerve growth factorganismsor (NGF) gene mediated by recombinant adenovirus (Ad-NGF) via peripheral transfection in mice with experimental autoimmune encephalomyelitis (EAE). Forty healthy female C57BL/6 mice were randomly divided into a control group, adenovirus (AdV) group, EAE group, and Ad-NGF transfection group; the control group received no treatment; the AdV group received adenovirus injection via the tail vein; the EAE and Ad-NGF transfection groups were induced with experimental autoimmune encephalomyelitis (EAE) using myelin oligodendrocyte glycoprotein 35-55 (MOG35-55), Ad-NGF transfection group received Ad-NGF injection via the tail vein, and daily neurological impairment scores were obtained. AQThe TUNEL method was employed to observe spinal neuron apoptosis in each group of mice; protein immunoblotting (western blot) and RT-PCR were used to measure NGF levels in the spinal cord tissues of each group, and western blotting was used to assess levels of cleaved caspase-3, Bax, and Bcl-2. ELISA and RT-PCR were employed to detect protein and mRNA levels of neuron-specific enolase (NSE) in spinal cord tissues, respectively. The control group and AdV mice did not develop symptoms. Compared to the EAE group, in the Ad-NGF transfection group, neurological function scores, TUNEL-positive cell counts, the ratio of NeuN + TUNEL to NeuN, levels of Bax and cleaved caspase-3 apoptotic proteins were significantly reduced, while Bcl-2 protein expression was increased. Expression levels of NGF, NGF-mRNA, NSE, and NSE-mRNA in spinal cord tissues were significantly elevated (P < 0.01). Immunofluorescence labeling revealed a significant punctate aggregation of apoptotic cells in spinal neurons of the EAE group, while the aggregation phenomenon was less pronounced in the Ad-NGF transfection group. Ad-NGF transfected by the periphery has a protective effect on spinal cord neurons in EAE mice by up-regulation NGF level, down-regulating apoptotic protein Caspase-3 in spinal cord neurons, inhibiting spinal cord neuron apoptosis and promoting NSE expression.

Transduced Olfactory Mucosa Cells Expressing Nerve Growth Factor for the Therapy of Experimental Spinal Cord Cysts.

A new gene-cell construct expressing nerve growth factor (NGF) has been developed. After obtaining engineered adenovectors Ad5-RGD-CAG-NGF and Ad5-RGD-CAG-EGFP, transduction efficiency and transgene expression were studied and multiplicity of infection was determined. The efficacy of transduced human olfactory ensheathing cells expressing NGF in restoring motor activity in rats has been shown in a limited period of time. Improved rat hindlimb mobility and cyst size reduction after gene-cell construct transplantation were more likely due to the cellular component of the construct.

Nerve growth factor promote VCAM-1-dependent monocyte adhesion and M2 polarization in osteosarcoma microenvironment: Implications for larotrectinib therapy.

Osteosarcoma is the most prevalent form of primary malignant bone tumor, primarily affecting children and adolescents. The nerve growth factors (NGF) referred to as neurotrophins have been associated with cancer-induced bone pain; however, the role of NGF in osteosarcoma has yet to be elucidated. In osteosarcoma samples from the Genomic Data Commons data portal, we detected higher levels of NGF and M2 macrophage markers, but not M1 macrophage markers. In cellular experiments, NGF-stimulated osteosarcoma conditional medium was shown to facilitate macrophage polarization from the M0 to the M2 phenotype. NGF also enhanced VCAM-1-dependent monocyte adhesion within the osteosarcoma microenvironment by down-regulating miR-513c-5p levels through the FAK and c-Src cascades. In in vivo xenograft models, the overexpression of NGF was shown to enhance tumor growth, while the oral administration of the TrK inhibitor larotrectinib markedly antagonized NGF-promoted M2 macrophage expression and tumor progression. These results suggest that larotrectinib could potentially be used as a therapeutic agent aimed at mitigating NGF-mediated osteosarcoma progression.

Human NGF "Painless" Ocular Delivery for Retinitis Pigmentosa: An In Vivo Study.

Retinitis pigmentosa (RP) is a family of genetically heterogeneous diseases still without a cure. Despite the causative genetic mutation typically not expressed in cone photoreceptors, these cells inevitably degenerate following the primary death of rods, causing blindness. The reasons for the "bystander" degeneration of cones are presently unknown but decrement of survival factors, oxidative stress, and inflammation all play a role. Targeting these generalized biological processes represents a strategy to develop mutation-agnostic therapies for saving vision in large populations of RP individuals. A classical method to support neuronal survival is by employing neurotrophic factors, such as NGF. This study uses painless human NGF (hNGFp), a TrkA receptor-biased variant of the native molecule with lower affinity for nociceptors and limited activity as a pain inducer; the molecule has identical neurotrophic power of the native form but a reduced affinity for the p75NTR receptors, known to trigger apoptosis. hNGFp has a recognized activity on brain microglial cells, which are induced to a phenotype switch from a highly activated to a more homeostatic configuration. hNGFp was administered to RP-like mice in vivo with the aim of decreasing retinal inflammation and also providing retinal neuroprotection. However, the ability of this treatment to counteract the bystander degeneration of cones remained limited.

Cisplatin induced alterations in nociceptor developmental trajectory elicits a TrkA dependent platinum-based chemotherapy induced neuropathic pain.

Cisplatin-based chemotherapy is a common treatment for paediatric cancer. Unfortunately, cisplatin treatment causes neuropathic pain, a highly prevalent adverse health related complication in adult childhood cancer survivors. Due to minimal understanding of this condition, there are currently no condition tailored analgesics available. Here we investigated an alteration in nociceptor maturation that results in neuronal sensitisation and manifestation of cisplatin induced survivorship pain in a TrkA dependent manner. Cisplatin was administered (i.p. 0.1 mg/kg Postnatal day 14 and 16) to neonatal male and female Wistar rats and nociceptive behavioural assays were performed. In vitro studies utilised isolated neonatal dorsal root ganglia sensory neurons treated with cisplatin (5 µg/ml) to elucidate impact upon nociceptor activation and neurite growth, in combination with TrkA inhibition (GW441756 10 nM and 100 nM). Cisplatin treated male and female neonatal Wistar rats developed a delayed but lasting mechanical and heat hypersensitivity. Cisplatin administration led to increased TrkA expression in dorsal root ganglia sensory neurons. Nerve growth factor (NGF) induced TrkA activation led to sensory neuritogenesis and nociceptor sensitisation, which could be prevented through pharmacological TrkA inhibition (GW441756 either s.c. 100 nM or i.p. 2 mg/kg). Administration of TrkA antagonist suppressed cisplatin induced TRPV1 mediated nociceptor sensitisation and prevented cisplatin induced neuropathic pain. These studies provide greater understanding of the underlying mechanisms that cause cisplatin induced childhood cancer survivorship pain and allowing identification of potential therapeutic targets.

Improving the Sensitivity of Protein Quantification by Immunoaffinity Liquid Chromatography─Triple Quadrupole Mass Spectrometry Using an Iterative Transition Summing Technique.

The desire to reach ever-diminishing lower limits of quantification (LLOQ) to probe changes in low abundance protein targets has led to enormous progress in sample preparation and liquid chromatography-tandem mass spectrometry (LC-MS/MS) instrumentation. To maximize signal and reduce noise, many approaches have been employed, including specific immunoaffinity (IA) enrichment and reducing the LC flow to the nanoflow (nLC) level; however, additional sensitivity gains may still be required. Recently, a technique termed "echo summing" has been described for small-molecular-weight analytes on a triple quadrupole (QqQ) MS where multiple iterations of the same, single selected reaction monitoring (SRM) transition are collected, summed, and integrated, yielding significant analyte dependent signal-to-noise (S/N) improvements. Herein, the direct applicability of echo summing to protein quantification by sequential IA combined with nLC-MS/MS (IA-nLC-MS/MS) is described for a beta nerve growth factor (NGF) and a soluble asialoglycoprotein receptor (sASGPR) assay from human serum. Five iterations of echo summing outperformed traditional collection in relative average accuracy (-1.5 ± 7.7 vs -41.7 ± 10.7% bias) and precision (7.8 vs 18.4% coefficient of variation (CV)) of the low-end quality control (QC) sample (N = 4) for NGF and improved functional sensitivity of serially diluted serum QC samples (N = 5 each population) approximately 2-fold (1.96 and 2.00-fold) for two peptides of sASGPR. Echo summing also extended the minimum quantifiable QC level for sASGPR 4-fold lower. Similar gains are believed to be achievable for most protein IA-nLC-MS/MS assays.

Efficacy and Safety of Nerve Growth Factor in Treating Neurotrophic Keratitis Patients: A Meta-Analysis.

Aims/Background Nerve growth factor has been approved for treating neurotrophic keratitis in Europe and the United States. However, its clinical efficacy and safety profile in neurotrophic keratitis patients have not been systematically evaluated. Therefore, this study systematically assessed the efficacy and safety of nerve growth factor (NGF) in treating patients with neurotrophic keratitis. Methods Various databases, including Wanfang, China National Knowledge Internet (CNKI), Embase, PubMed, and Web of Science were systematically searched. This search included all articles published up to January 2024. Moreover, these articles were thoroughly reviewed and carefully screened following predetermined inclusion and exclusion criteria. Furthermore, the quality of the included studies was assessed using the Cochrane Risk of Bias Manual 5.3 (The Cochrane Collaboration, London, UK). Stata26.0 (StataCorp LLC, College Station, TX, USA) was used for meta-analysis. The outcome indicators evaluated in this study included corneal healing efficiency, corneal complete healing rate, best vision correction rate, ailment progression, and the number of adverse events. Results A total of 4 articles were included in this study, including 293 sufferers. The findings from the meta-analysis revealed that the corneal healing efficiency (odds ratio (OR) = 1.72, 95% confidence interval (CI): 1.20-2.45), the corneal complete healing rate (OR = 2.23, 95% CI: 1.41-3.54), and the best visual acuity correction rate (OR = 1.97, 95% CI: 1.11-3.47) were significantly higher in the experimental group compared to the control group. However, the incidence of ailment progression (OR = 0.44, 95% CI: 0.17-1.13) and adverse events (OR = 0.88, 95% CI: 0.50-1.56) did not show significant differences between these two groups. Conclusion In summary, for patients with neuropathic keratitis, NGF treatment can promote corneal healing efficiency, effectively improve visual correction, and reduce disease progression and incidence of adverse events to a large extent. The clinical effect and safety are high, and it is worthy of clinical promotion and application.