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1.
PLoS One ; 19(5): e0302742, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38768144

RESUMEN

Zeaxanthin dipalmitate (ZD) is a chemical extracted from wolfberry that protects degenerated photoreceptors in mouse retina. However, the pure ZD is expensive and hard to produce. In this study, we developed a method to enrich ZD from wolfberry on a production line and examined whether it may also protect the degenerated mouse retina. The ZD-enriched wolfberry extract (ZDE) was extracted from wolfberry by organic solvent method, and the concentration of ZD was identified by HPLC. The adult C57BL/6 mice were treated with ZDE or solvent by daily gavage for 2 weeks, at the end of the first week the animals were intraperitoneally injected with N-methyl-N-nitrosourea to induce photoreceptor degeneration. Then optomotor, electroretinogram, and immunostaining were used to test the visual behavior, retinal light responses, and structure. The final ZDE product contained ~30mg/g ZD, which was over 9 times higher than that from the dry fruit of wolfberry. Feeding degenerated mice with ZDE significantly improved the survival of photoreceptors, enhanced the retinal light responses and the visual acuity. Therefore, our ZDE product successfully alleviated retinal morphological and functional degeneration in mouse retina, which may provide a basis for further animal studies for possible applying ZDE as a supplement to treat degenerated photoreceptor in the clinic.


Asunto(s)
Modelos Animales de Enfermedad , Lycium , Ratones Endogámicos C57BL , Células Fotorreceptoras de Vertebrados , Extractos Vegetales , Degeneración Retiniana , Zeaxantinas , Animales , Lycium/química , Degeneración Retiniana/tratamiento farmacológico , Degeneración Retiniana/patología , Ratones , Extractos Vegetales/farmacología , Extractos Vegetales/química , Zeaxantinas/farmacología , Células Fotorreceptoras de Vertebrados/efectos de los fármacos , Células Fotorreceptoras de Vertebrados/patología , Electrorretinografía , Retina/efectos de los fármacos , Retina/patología , Retina/metabolismo , Visión Ocular/efectos de los fármacos , Masculino , Xantófilas/farmacología
2.
Mol Psychiatry ; 2024 May 04.
Artículo en Inglés | MEDLINE | ID: mdl-38704506

RESUMEN

Autism spectrum disorder (ASD) encompasses a range of neurodevelopmental conditions. Different mutations on a single ASD gene contribute to heterogeneity of disease phenotypes, possibly due to functional diversity of generated isoforms. SHANK2, a causative gene in ASD, demonstrates this phenomenon, but there is a scarcity of tools for studying endogenous SHANK2 proteins in an isoform-specific manner. Here, we report a point mutation on SHANK2, which is found in a patient with autism, located on exon of the SHANK2B transcript variant (NM_133266.5), hereby SHANK2BY29X. This mutation results in an early stop codon and an aberrant splicing event that impacts SHANK2 transcript variants distinctly. Induced pluripotent stem cells (iPSCs) carrying this mutation, from the patient or isogenic editing, fail to differentiate into functional dopamine (DA) neurons, which can be rescued by genetic correction. Available SMART-Seq single-cell data from human midbrain reveals the abundance of SHANK2B transcript in the ALDH1A1 negative DA neurons. We then show that SHANK2BY29X mutation primarily affects SHANK2B expression and ALDH1A1 negative DA neurons in vitro during early neuronal developmental stage. Mice knocked in with the identical mutation exhibit autistic-like behavior, decreased occupancy of ALDH1A1 negative DA neurons and decreased dopamine release in ventral tegmental area (VTA). Our study provides novel insights on a SHANK2 mutation derived from autism patient and highlights SHANK2B significance in ALDH1A1 negative DA neuron.

3.
Neural Regen Res ; 19(12): 2588-2601, 2024 Dec 01.
Artículo en Inglés | MEDLINE | ID: mdl-38595278

RESUMEN

It has long been asserted that failure to recover from central nervous system diseases is due to the system's intricate structure and the regenerative incapacity of adult neurons. Yet over recent decades, numerous studies have established that endogenous neurogenesis occurs in the adult central nervous system, including humans'. This has challenged the long-held scientific consensus that the number of adult neurons remains constant, and that new central nervous system neurons cannot be created or renewed. Herein, we present a comprehensive overview of the alterations and regulatory mechanisms of endogenous neurogenesis following central nervous system injury, and describe novel treatment strategies that target endogenous neurogenesis and newborn neurons in the treatment of central nervous system injury. Central nervous system injury frequently results in alterations of endogenous neurogenesis, encompassing the activation, proliferation, ectopic migration, differentiation, and functional integration of endogenous neural stem cells. Because of the unfavorable local microenvironment, most activated neural stem cells differentiate into glial cells rather than neurons. Consequently, the injury-induced endogenous neurogenesis response is inadequate for repairing impaired neural function. Scientists have attempted to enhance endogenous neurogenesis using various strategies, including using neurotrophic factors, bioactive materials, and cell reprogramming techniques. Used alone or in combination, these therapeutic strategies can promote targeted migration of neural stem cells to an injured area, ensure their survival and differentiation into mature functional neurons, and facilitate their integration into the neural circuit. Thus can integration replenish lost neurons after central nervous system injury, by improving the local microenvironment. By regulating each phase of endogenous neurogenesis, endogenous neural stem cells can be harnessed to promote effective regeneration of newborn neurons. This offers a novel approach for treating central nervous system injury.

4.
Neural Regen Res ; 19(12): 2773-2784, 2024 Dec 01.
Artículo en Inglés | MEDLINE | ID: mdl-38595294

RESUMEN

JOURNAL/nrgr/04.03/01300535-202412000-00032/figure1/v/2024-04-08T165401Z/r/image-tiff For patients with chronic spinal cord injury, the conventional treatment is rehabilitation and treatment of spinal cord injury complications such as urinary tract infection, pressure sores, osteoporosis, and deep vein thrombosis. Surgery is rarely performed on spinal cord injury in the chronic phase, and few treatments have been proven effective in chronic spinal cord injury patients. Development of effective therapies for chronic spinal cord injury patients is needed. We conducted a randomized controlled clinical trial in patients with chronic complete thoracic spinal cord injury to compare intensive rehabilitation (weight-bearing walking training) alone with surgical intervention plus intensive rehabilitation. This clinical trial was registered at ClinicalTrials.gov (NCT02663310). The goal of surgical intervention was spinal cord detethering, restoration of cerebrospinal fluid flow, and elimination of residual spinal cord compression. We found that surgical intervention plus weight-bearing walking training was associated with a higher incidence of American Spinal Injury Association Impairment Scale improvement, reduced spasticity, and more rapid bowel and bladder functional recovery than weight-bearing walking training alone. Overall, the surgical procedures and intensive rehabilitation were safe. American Spinal Injury Association Impairment Scale improvement was more common in T7-T11 injuries than in T2-T6 injuries. Surgery combined with rehabilitation appears to have a role in treatment of chronic spinal cord injury patients.

5.
Nat Commun ; 15(1): 3034, 2024 Apr 08.
Artículo en Inglés | MEDLINE | ID: mdl-38589429

RESUMEN

Chronic stress induces anxiety disorders via both neural pathways and circulating factors. Although many studies have elucidated the neural circuits involved in stress-coping behaviors, the origin and regulatory mechanism of peripheral cytokines in behavioural regulation under stress conditions are not fully understood. Here, we identified a serum cytokine, lipocalin 2 (LCN2), that was upregulated in participants with anxiety disorders. Using a mouse model of chronic restraint stress (CRS), circulating LCN2 was found to be related to stress-induced anxiety-like behaviour via modulation of neural activity in the medial prefrontal cortex (mPFC). These results suggest that stress increases hepatic LCN2 via a neural pathway, leading to disrupted cortical functions and behaviour.


Asunto(s)
Ansiedad , Corteza Prefrontal , Humanos , Lipocalina 2/metabolismo , Corteza Prefrontal/fisiología , Ansiedad/metabolismo , Trastornos de Ansiedad , Hígado/metabolismo
6.
Neural Regen Res ; 19(10): 2290-2298, 2024 Oct 01.
Artículo en Inglés | MEDLINE | ID: mdl-38488563

RESUMEN

JOURNAL/nrgr/04.03/01300535-202410000-00030/figure1/v/2024-02-06T055622Z/r/image-tiff Photoreceptor cell degeneration leads to blindness, for which there is currently no effective treatment. Our previous studies have shown that Lycium barbarum (L. barbarum) polysaccharide (LBP) protects degenerated photoreceptors in rd1, a transgenic mouse model of retinitis pigmentosa. L. barbarum glycopeptide (LbGP) is an immunoreactive glycoprotein extracted from LBP. In this study, we investigated the potential protective effect of LbGP on a chemically induced photoreceptor-degenerative mouse model. Wild-type mice received the following: oral administration of LbGP as a protective pre-treatment on days 1-7; intraperitoneal administration of 40 mg/kg N-methyl-N-nitrosourea to induce photoreceptor injury on day 7; and continuation of orally administered LbGP on days 8-14. Treatment with LbGP increased photoreceptor survival and improved the structure of photoreceptors, retinal photoresponse, and visual behaviors of mice with photoreceptor degeneration. LbGP was also found to partially inhibit the activation of microglia in N-methyl-N-nitrosourea-injured retinas and significantly decreased the expression of two pro-inflammatory cytokines. In conclusion, LbGP effectively slowed the rate of photoreceptor degeneration in N-methyl-N-nitrosourea-injured mice, possibly through an anti-inflammatory mechanism, and has potential as a candidate drug for the clinical treatment of photoreceptor degeneration.

8.
NPJ Regen Med ; 9(1): 4, 2024 Jan 20.
Artículo en Inglés | MEDLINE | ID: mdl-38242900

RESUMEN

Neuromyelitis optica (NMO) is a severe autoimmune inflammatory disease of the central nervous system that affects motor function and causes relapsing disability. Human umbilical cord-derived mesenchymal stem cells (hUC-MSCs) have been used extensively in the treatment of various inflammatory diseases, due to their potent regulatory roles that can mitigate inflammation and repair damaged tissues. However, their use in NMO is currently limited, and the mechanism underlying the beneficial effects of hUC-MSCs on motor function in NMO remains unclear. In this study, we investigate the effects of hUC-MSCs on the recovery of motor function in an NMO systemic model. Our findings demonstrate that milk fat globule epidermal growth 8 (MFGE8), a key functional factor secreted by hUC-MSCs, plays a critical role in ameliorating motor impairments. We also elucidate that the MFGE8/Integrin αvß3/NF-κB signaling pathway is partially responsible for structural and functional recovery, in addition to motor functional enhancements induced by hUC-MSC exposure. Taken together, these findings strongly support the involvement of MFGE8 in mediating hUC-MSCs-induced improvements in motor functional recovery in an NMO mouse model. In addition, this provides new insight on the therapeutic potential of hUC-MSCs and the mechanisms underlying their beneficial effects in NMO.

9.
Neural Regen Res ; 19(9): 2036-2040, 2024 Sep 01.
Artículo en Inglés | MEDLINE | ID: mdl-38227533

RESUMEN

JOURNAL/nrgr/04.03/01300535-202409000-00036/figure1/v/2024-01-16T170235Z/r/image-tiff Strong evidence has accumulated to show a correlation between depression symptoms and inflammatory responses. Moreover, anti-inflammatory treatment has shown partial effectiveness in alleviating depression symptoms. Lycium barbarum polysaccharide (LBP), derived from Goji berries, exhibits notable antioxidative and anti-inflammatory properties. In our recent double-blinded randomized placebo-controlled trial, we found that LBP significantly reduced depressive symptoms in adolescents with subthreshold depression. It is presumed that the antidepressant effect of LBP may be associated with its influence on inflammatory cytokines. In the double-blinded randomized controlled trial, we enrolled 29 adolescents with subthreshold depression and randomly divided them into an LBP group and a placebo group. In the LBP group, adolescents were given 300 mg/d LBP. A 6-week follow up was completed by 24 adolescents, comprising 14 adolescents from the LBP group (15.36 ± 2.06 years, 3 men and 11 women) and 10 adolescents from the placebo group (14.9 ± 1.6 years, 2 men and 8 women). Our results showed that after 6 weeks of treatment, the interleukin-17A level in the LBP group was lower than that in the placebo group. Network analysis showed that LBP reduced the correlations and connectivity between inflammatory factors, which were associated with the improvement in depressive symptoms. These findings suggest that 6-week administration of LBP suppresses the immune response by reducing interleukin-17A level, thereby exerting an antidepressant effect.

10.
Adv Ophthalmol Pract Res ; 3(2): 47-54, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37846375

RESUMEN

Background: Artesunate (ART), a member of the artemisinin family, possesses multi-properties, including anti-inflammation, anti-oxidation, and anti-tumor. ART was recently reported to show anti-neovascularization effect on the cornea, iris, and retina. Compared to the expensive anti-VEGF treatment, this versatile, economical treatment option is attractive in the ophthalmic field. The safety and toxicity profile of ART intravitreal application are in utmost need. Methods: In this study, immortalized microglial (IMG) cells were treated with ART to determine the safe concentrations without inducing overt inflammatory reactions. Reverse transcription-polymerase chain reaction analysis was used to detect the cytokine expressions in IMG cells in response to ART stimulation. Various doses of ART were intravitreally injected into the right eyes of C57BL/6 mice. Retinal function was tested by electroretinogram, and retinal ganglion cell (RGC) survival was evaluated by counting Brn3a stained cells in flat-mounted retinas at 7 days after ART injection. Results: ART below 5µM was safe for IMG cells in vitro. Both 2.5 and 5 â€‹µM ART treatment increased IL-10 gene expression in IMG cells while not changing IL-1ß, IL-6, TNF-α, and Arg-1. In the in vivo study, intravitreal injection of ART below 100 â€‹µM did not cause deterioration in the retinal function and RGC survival of the mouse eyes, while 1 â€‹mM ART treatment significantly attenuated both the scotopic and photopic b-wave amplitudes and impaired RGC survival. In addition, treatment with ART of 25, 50, and 100 â€‹µM significantly decreased TNF-α gene expression while ART of 100 â€‹µM significantly increased IL-10 in the mouse retina. Conclusions: Intravitreal injection of 100 â€‹µM ART could downregulate TNF-α while upregulate IL-10 in the mouse retina without causing retinal functional deterioration and RGC loss. ART might be used as anti-inflammatory agent for retinal disorders.

11.
PLoS Biol ; 21(9): e3002282, 2023 09.
Artículo en Inglés | MEDLINE | ID: mdl-37676855

RESUMEN

Light in the environment greatly impacts a variety of brain functions, including sleep. Clinical evidence suggests that bright light treatment has a beneficial effect on stress-related diseases. Although stress can alter sleep patterns, the effect of bright light treatment on stress-induced sleep alterations and the underlying mechanism are poorly understood. Here, we show that bright light treatment reduces the increase in nonrapid eye movement (NREM) sleep induced by chronic stress through a di-synaptic visual circuit consisting of the thalamic ventral lateral geniculate nucleus and intergeniculate leaflet (vLGN/IGL), lateral habenula (LHb), and rostromedial tegmental nucleus (RMTg). Specifically, chronic stress causes a marked increase in NREM sleep duration and a complementary decrease in wakefulness time in mice. Specific activation of RMTg-projecting LHb neurons or activation of RMTg neurons receiving direct LHb inputs mimics the effects of chronic stress on sleep patterns, while inhibition of RMTg-projecting LHb neurons or RMTg neurons receiving direct LHb inputs reduces the NREM sleep-promoting effects of chronic stress. Importantly, we demonstrate that bright light treatment reduces the NREM sleep-promoting effects of chronic stress through the vLGN/IGL-LHb-RMTg pathway. Together, our results provide a circuit mechanism underlying the effects of bright light treatment on sleep alterations induced by chronic stress.


Asunto(s)
Habénula , Sueño de Onda Lenta , Animales , Ratones , Sueño , Núcleo Celular , Cuerpos Geniculados
12.
Sci Bull (Beijing) ; 68(18): 2063-2076, 2023 09 30.
Artículo en Inglés | MEDLINE | ID: mdl-37586975

RESUMEN

Despite significant advancements in our understanding of addiction at the neurobiological level, a highly effective extinction procedure for preventing relapse remains elusive. In this study, we report that bright light treatment (BLT) administered during cocaine withdrawal with extinction training prevents cocaine-driven reinstatement by acting through the thalamic-habenular pathway. We found that during cocaine withdrawal, the lateral habenula (LHb) was recruited, and inhibition of the LHb via BLT prevented cocaine-driven reinstatement. We also demonstrated that the effects of BLT were mediated by activating LHb-projecting neurons in the ventral lateral geniculate nucleus and intergeniculate leaflet (vLGN/IGL) or by inhibiting postsynaptic LHb neurons. Furthermore, BLT was found to improve aversive emotional states induced by drug withdrawal. Our findings suggest that BLT administered during the cocaine withdrawal may be a promising strategy for achieving drug abstinence.


Asunto(s)
Cocaína , Habénula , Humanos , Cocaína/metabolismo , Neuronas , Tálamo , Recurrencia
13.
Neural Regen Res ; 18(12): 2623-2632, 2023 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-37449600

RESUMEN

In recent years, the pharmacological benefits of herbal extracts have been revisited for their potential neuroprotective effects in glaucoma. The polysaccharides extracted from the fruits of Lycium barbarum L., or Lycium barbarum polysaccharides, exert their anti-aging effect through reducing oxidative stress, modulating the immune response, enhancing neuronal responses, and promoting cytoprotection. The therapeutic efficacy of Lycium barbarum polysaccharides in preserving retinal ganglion cells and their functions was demonstrated in a range of experimental models of optic neuropathies. These include the acute and chronic ocular hypertension models, the partial optic nerve transection model, and the ischemic-reperfusion injuries model. Based on these findings, Lycium barbarum polysaccharides appear to be a good candidate to be developed as a neuroprotective agent for treating multifactorial diseases. This review aims to present a comprehensive review on the latest preclinical evidence on the pre- and post-treatment benefits of Lycium barbarum polysaccharides in retinal ganglion cell neuroprotection. The possible mechanisms of Lycium barbarum polysaccharides mediating retinal ganglion cell neuroprotection will also be described. Moreover, the potential research gaps in the effective translation of Lycium barbarum polysaccharides treatment into clinical glaucoma management will be discussed.

14.
Front Aging Neurosci ; 15: 1156265, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37469953

RESUMEN

Introduction: Lycium barbarum glycopeptide (LbGp) is the main bioactive compound extracted from the traditional Chinese medicine. L. barbarum berries and has been proven to have numerous health benefits, including antioxidative, anti-inflammatory, anticancer, and cytoprotective activities. However, the antiaging effect of LbGp remains unknown. Methods: The lifespan and body movement of C. elegans were used to evaluate the effect of LbGp on lifespan and health span. The thrashing assay was used to determine the role of LbGp in Parkinson's disease. To investigate the mechanisms of LbGp-induced antiaging effects, we analyzed changes in lifespan, movement, and the expression of longevity-related genes in a series of worm mutants after LbGp treatment. Results: We found that LbGp treatment prolonged the lifespan and health span of C. elegans. Mechanistically, we found that LbGp could activate the transcription factors DAF-16/FOXO, SKN-1/Nrf2, and HSF-1, as well as the nuclear receptor DAF-12, thereby upregulating longevity-related genes to achieve lifespan extension. In addition, we found that the lifespan extension induced by LbGp partially depends on mitochondrial function. Intriguingly, LbGp also ameliorated neurodegenerative diseases such as Parkinson's disease in a DAF-16-, SKN-1-, and HSF-1-dependent manner. Conclusion: Our work suggests that LbGp might be a viable candidate for the treatment and prevention of aging and age-related diseases.

15.
Commun Biol ; 6(1): 624, 2023 06 09.
Artículo en Inglés | MEDLINE | ID: mdl-37296310

RESUMEN

Aerobic exercise effectively ameliorates mental disorders including anxiety and depression. Current findings mainly attribute its neural mechanism to the improvement of adult neurogenesis, while leaving the possible circuitry mechanism unclear. In the current study, we identify the overexcitation of the medial prefrontal cortex (mPFC) to basolateral amygdala (BLA) pathway under chronic restraint stress (CRS), and 14-day treadmill exercise selectively reverses such abnormalities. Using chemogenetic approaches, we find that the mPFC-BLA circuit is necessary for preventing anxiety-like behaviors in CRS mice. These results collectively suggest a neural circuitry mechanism by which exercise training improves the resilience against environmental stress.


Asunto(s)
Amígdala del Cerebelo , Complejo Nuclear Basolateral , Ratones , Animales , Corteza Prefrontal/metabolismo , Complejo Nuclear Basolateral/metabolismo , Ansiedad/prevención & control , Ansiedad/metabolismo , Ejercicio Físico
16.
Glia ; 71(8): 1985-2004, 2023 08.
Artículo en Inglés | MEDLINE | ID: mdl-37186402

RESUMEN

Neural repair is highly influenced by reactive astrocytes. Atypical cadherin Celsr2 regulates neuron development and axon regeneration, while its role in glial cells remains unexplored. In this study, we show that Celsr2 is highly expressed in spinal astrocytes of adult mice, and knockout of Celsr2 results in reactive astrocytes with longer protrusions preferentially orientated towards lesion borders in culture scratch assay and injured spinal cord, and elevation of total and active Cdc42 and Rac1 protein in western blots. Inactivation of Celsr2 enhances calcium influx in reactive astrocytes in time-lapse imaging. Morphological phenotypes of cultured Celsr2-/- astrocytes are rescued by Cdc42 or Rac1 inhibitors. Following spinal cord injury (SCI), Celsr2-/- mice exhibit smaller lesion cavity and glial scar, enhanced fiber regeneration, weaker microglial response, and improved functional recovery than control animals. Similar phenotypes are found in mice with conditional knockout of Celsr2 in astrocytes. In Celsr2-/- mice, astrocyte phenotype is changed and neuroinflammation is alleviated after injury. Inhibiting Cdc42/Rac1 activities compromises astrocyte polarization and the improvement of neural repair and functional recovery in Celsr2-/- mice with SCI. In conclusion, Celsr2 regulates morphological polarization and functional phenotype of reactive astrocytes and inactivating Celsr2 is a potential therapeutic strategy for neural repair.


Asunto(s)
Astrocitos , Traumatismos de la Médula Espinal , Ratones , Animales , Astrocitos/metabolismo , Axones/metabolismo , Regeneración Nerviosa/fisiología , Traumatismos de la Médula Espinal/metabolismo , Fenotipo , Cadherinas/metabolismo
17.
Phytomedicine ; 116: 154864, 2023 Jul 25.
Artículo en Inglés | MEDLINE | ID: mdl-37182278

RESUMEN

BACKGROUND: Lycium barbarum (Wolfberry) extract has been shown to be effective in neuroprotection against aging or neural injury. Knowledge of its potential roles and biological mechanisms in relieving mental disorders, however, remains limited. PURPOSE: To investigate the potency of Lycium barbarum glycopeptide (LbGp) in alleviating anxiety disorders and the related biological mechanisms. METHODS: LbGp was administrated to mice subjected to 14 days of chronic restrain stress (CRS) via the intragastric route. The anxiolytic effect was evaluated by a battery of behavioral assays. The morphology of neurons and glial cells was evaluated, and cortical neuronal calcium transients were recorded in vivo. The molecular mechanism of LbGp was also investigated. RESULTS: LbGp effectively relieved anxiety-like and depressive behaviors under CRS. Mechanistic studies further showed that LbGp treatment relieved oxidative stress and lipid peroxidation in the medial prefrontal cortex (mPFC). In particular, the ferroptosis pathway was inhibited by LbGp, revealing a previously unrecognized mechanism of the anxiolytic role of wolfberry extract. CONCLUSION: In summary, our results supported the future development of LbGp to prevent or ameliorate stress-induced anxiety disorders. Our work provides a promising strategy for early intervention for pateitents with mental disorders by applying natural plant extracts.


Asunto(s)
Ferroptosis , Lycium , Ratones , Animales , Lycium/química , Glicopéptidos/farmacología , Estrés Oxidativo , Extractos Vegetales/farmacología , Extractos Vegetales/uso terapéutico , Trastornos de Ansiedad/tratamiento farmacológico , Ansiedad , Corteza Prefrontal
18.
Regen Biomater ; 10: rbad038, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37215435

RESUMEN

Currently, more and more patients suffer from peripheral nerve injury due to trauma, tumor and other causes worldwide. Biomaterial-based nerve conduits are increasingly recognized as a potential alternative to nerve autografts for the treatment of peripheral nerve injury. However, an ideal nerve conduit must offer topological guidance and biochemical and electrical signal transduction mechanisms. In this work, aligned conductive nanofibrous scaffolds comprising polylactic-co-glycolic acid and multiwalled carbon nanotubes (MWCNTs) were fabricated via coaxial electrospinning, and nerve growth factor (NGF) and Lycium barbarum polysaccharides (LBP) purified from the wolfberry were loaded on the core and shell layers of the nanofibers, respectively. LBP were confirmed to accelerate long-distance axon regeneration after severe peripheral nerve injury. In addition, the synergistic promotion of LBP and NGF on nerve cell proliferation and neurite outgrowth was demonstrated. MWCNTs were introduced into the aligned fibers to further increase the electrical conductivity, which promoted the directional growth and neurite extension of neurons in vitro. Further, the combination of conductive fibrous scaffolds with electrical stimulation that mimics endogenous electric fields significantly promoted the differentiation of PC12 cells and the axon outgrowth of neurons. Based on robust cell-induced behaviors, conductive composite fibers with optimized fiber alignment may be used for the promotion of nerve recovery.

19.
Cell Rep ; 42(3): 112240, 2023 03 28.
Artículo en Inglés | MEDLINE | ID: mdl-36924491

RESUMEN

The aggregation of TAR DNA binding protein 43 kDa (TDP-43) is related to different neurodegenerative diseases, which leads to microglial activation and neuronal loss. The molecular mechanism driving neuronal death by reactive microglia, however, has not been completely resolved. In this study, we generated a mouse model by overexpressing mutant human TDP-43 (M337V) in the primary motor cortex, leading to prominent motor-learning deficits. In vivo 2-photon imaging shows an active approach of microglia toward parvalbumin interneurons, resulting in disrupted cortical excitatory-inhibitory balance. Proteomics studies suggest that activation of the complement pathway induces microglial activity. To develop an early interventional strategy, treadmill exercise successfully prevents the deterioration of motor dysfunction under enhanced adipocytic release of clusterin to block the complement pathway. These results demonstrate a previously unrecognized pathway by which TDP-43 induces cortical deficits and provide additional insights for the mechanistic explanation of exercise training in disease intervention.


Asunto(s)
Esclerosis Amiotrófica Lateral , Enfermedades Neurodegenerativas , Animales , Humanos , Ratones , Esclerosis Amiotrófica Lateral/genética , Proteínas de Unión al ADN/genética , Proteínas de Unión al ADN/metabolismo , Ratones Transgénicos , Microglía/metabolismo , Enfermedades Neurodegenerativas/metabolismo , Condicionamiento Físico Animal
20.
J Control Release ; 357: 1-19, 2023 05.
Artículo en Inglés | MEDLINE | ID: mdl-36958402

RESUMEN

Mesenchymal stem cells (MSCs) have shown promise for the therapy of cerebral ischemia in animal studies and clinical trials, yet their clinical application still faces many challenges. Utilizing small extracellular vesicles (sEVs) may overcome these challenges. In the study, we overexpressed brain-derived neurotrophic factor (BDNF) in cultured MSCs and purified sEVs using anion exchange chromatography. In an ischemic stroke mouse model, sEVs selectively targeted the peri-infarct region after intranasal administration, and BDNF loading enhanced the efficacy of sEVs in improved functional behavior, neural repair indicated by infarct volume reduction, increased neurogenesis, angiogenesis, synaptic plasticity, and fiber preservation, as well as decreased inflammatory-cytokine expression and glial response. Intranasal administration of sEVs and BDNF-sEVs resulted in upregulation of neuroprotection-related genes and downregulation of inflammation-related genes, and BDNF-sEVs treatment activated the BDNF/TrkB signaling in the ischemic brain. Transcriptomic and proteomic analysis of sEVs and BDNF-sEVs disclosed abundant proteins and miRNAs involved in neuroprotection and anti-inflammation, and BDNF-sEVs showed different characteristics from sEVs. In conclusion, intranasal delivery of sEVs-loaded BDNF is a promising alternative strategy for the therapy of cerebral ischemia.


Asunto(s)
Isquemia Encefálica , Vesículas Extracelulares , Ratones , Animales , Factor Neurotrófico Derivado del Encéfalo/genética , Administración Intranasal , Proteómica , Isquemia Encefálica/tratamiento farmacológico , Isquemia Encefálica/metabolismo , Infarto/tratamiento farmacológico , Vesículas Extracelulares/metabolismo
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