Hangekobokuto, a traditional Japanese herbal medicine, ameliorates postoperative ileus through its anti-inflammatory action.

BACKGROUND/AIMS: Gastroprokinetic agents are used for patients with postoperative ileus (POI), and the Japanese traditional herbal medicine daikenchuto (DKT) is one such agent used in the clinical setting. POI is caused by inflammation. DKT and rikkunshito have anti-inflammatory abilities in addition to their gastroprokinetic effects. The efficacy of Kampo formulations, including hangekobokuto (HKT), in patients with POI has been reported recently. Several authors have described the efficacy of honokiol, the primary component of Magnoliae Cortex, in HKT in mouse models of POI. We therefore analyzed the effect of HKT on POI model mice to determine the similarities in the mechanism of action between HKT and DKT. METHODS: HKT was administered orally to each mouse before and after intestinal manipulation was performed on the distal ileum. The gastrointestinal transit in vivo, leukocyte infiltration, and levels of inflammatory mediators, such as cytokines and chemokines, were analyzed. RESULTS: HKT significantly inhibited the infiltration of neutrophils and macrophages and led to the recovery of delayed intestinal transit. In addition, it significantly decreased inducible nitric oxide synthase (iNOS) as well as honokiol levels, suggesting anti-inflammatory activity. However, it did not inhibit the increase in levels of interleukin (IL)-1beta and IL-6, which are related to iNOS induction. In contrast, HKT increased levels of nerve growth factor (NGF) and suppressed those of nuclear factor-κB (NFκB), which are related to iNOS induction, suggesting the possibility of a neuronal anti-inflammatory mechanism. CONCLUSIONS: HKT exerted a POI-relieving effect similar to DKT in a murine POI model, and findings suggest that it may exert its anti-inflammatory activity through NGF.

Unveiling the effect of Withania somnifera on neuronal cytoarchitecture and synaptogenesis: A combined in vitro and network pharmacology approach.

Withania somnifera (WS), is known for its remarkable contribution in herbal medicine and Ayurveda, which is therapeutically applied to improve memory and anxiety in patients. However, the pharmacological details of this plant on memory boosting yet remained undefined. This study provides mechanistic insights on the effect of ethanol solution extract of the whole plant of WS (WSEE) on neuritogenesis by combining in vitro and in silico network pharmacology approaches. WSEE promoted significant neuronal growth through early differentiation, axodendritic arborization, and synaptogenesis on primary hippocampal neurons. The network pharmacological study confirmed that the neuritogenic activity is potentially mediated by modulating the neurotrophin signaling pathway, where NRTK1 (TrkA) was revealed as the primary target of WS secondary metabolites. This neurotrophic activity of WSEE was significantly stifled by the presence of TrkA inhibitor, which further confirms the TrkA-dependent activity of WSEE. In addition, a molecular docking study suggested steroidal lactones present in the WS might act as nerve growth factor (NGF)-mimetics, activating TrkA by binding to the NGF-binding domain. As a whole, the findings of the study suggest a significant role of WSEE on neuritogenesis and its potential to function as a therapeutic agent and in drug designing for the prevention and treatment of memory-related neurological disorders.

A diselenide bond-containing ROS-responsive ruthenium nanoplatform delivers nerve growth factor for Alzheimer's disease management by repairing and promoting neuron regeneration.

Alzheimer's disease (AD) is an incurable neurodegenerative disease. Repairing damaged nerves and promoting nerve regeneration are key ways to relieve AD symptoms. However, due to the lack of effective strategies to deliver nerve growth factor (NGF) to the brain, achieving neuron regeneration is a major challenge for curing AD. Herein, a ROS-responsive ruthenium nanoplatform (R@NGF-Se-Se-Ru) drug delivery system for AD management by promoting neuron regeneration and Aß clearance was investigated. Under near-infrared (NIR) irradiation, nanoclusters have good photothermal properties, which can effectively inhibit the aggregation of Aß and disaggregate Aß fibrils. Interestingly, the diselenide bond in the nanoclusters is broken, and the nanoclusters are degraded into small ruthenium nanoparticles in the high reactive oxygen species (ROS) environment of the diseased area. Besides, NGF can promote neuronal regeneration and repair damaged nerves. Furthermore, R@NGF-Se-Se-Ru efficiently crosses the blood-brain barrier (BBB) owing to the covalently grafted target peptides of RVG (R). In vivo studies demonstrate that R@NGF-Se-Se-Ru nanoclusters decrease Aß deposits, inhibit Aß-induced cytotoxicity, and promote neurite outgrowth. The study confirms that promoting both Aß clearance and neuron regeneration is an important therapeutic target for anti-AD drugs and provides a novel insight for AD therapy.

Comparison of Therapeutic Results with/without Additional Hyperbaric Oxygen Therapy in Idiopathic Sudden Sensorineural Hearing Loss: A Randomized Prospective Study.

OBJECTIVE: To assess the efficacy of the combination of hyperbaric oxygen (HBO) and pharmacological treatment in patients with idiopathic sudden sensorineural hearing loss (ISSNHL) and define patients amenable for HBO therapy. METHODS: Prospective, randomized, trial involving 136 cases with unilateral ISSNHL that were randomly divided into 2 groups: the pharmacological treatment (P) group and HBO + pharmacological treatment (HBO+P) group, which received additional HBO for 14 days besides the pharmacological treatments. Pure tone audiometry gain larger than 15 dBHL was defined as success, and the success rate of each group was calculated. RESULTS: The overall success rate of the HBO+P group and the P group is 60.6% (40/66) and 42.9% (30/70), respectively (p < 0.05). Furthermore, patients with mild-moderate baseline hearing loss, aged ≤50 years, receiving treatment in ≤14 days, or without accompanied dizziness/vertigo in the HBO+P group had higher success rate than the P group (p < 0.05). CONCLUSIONS: HBO combined with pharmacological treatments leads to better hearing recovery than pharmacological treatments alone.

Nasal delivery of nerve growth factor rescue hypogonadism by up-regulating GnRH and testosterone in aging male mice.

BACKGROUND: Nerve growth factor (NGF) plays essential roles in regulating the development and maintenance of central sympathetic and sensory neurons. However, the effects of NGF on hypogonadism remain unexplored. METHODS: To assess the effects of NGF on hypogonadism, we established a convenient and noninvasive way to deliver NGF to the hypothalamus by spraying liposome-encapsulated NGF into the nasal cavity. The ten-month-old aging male senescence accelerate mouse P8 (SAMP8) mice with age-related hypogonadotrophic hypogonadism were used to study the role of NGF in hypogonadism. The age-matched accelerated senescence-resistant mouse R1 (SAMR1) served as a control. The ten-month-old SAMP8 mice were treated with NGF twice per week for 12 weeks. Sexual hormones, sexual behaviors, and fertility were analyzed after NGF treatment. And the mechanisms of NGF in sex hormones sexual function were also studied. FINDINGS: NGF could enhance the sexual function, improve the quality of the sperm, and restore the fertility of aging male SAMP8 mice with age-related hypogonadism by activating gonadotropin-releasing hormone (GnRH) neuron and regulating secretion of GnRH. And NGF regulated the GnRH release through the PKC/p-ERK1/2/p-CREB signal pathway. INTERPRETATION: These results suggest that NGF treatment could alleviate various age-related hypogonadism symptoms in male SAMP8 and may be usefulness for age-related hypogonadotrophic hypogonadism and its related subfertility. FUND: National Natural Science Foundation of China, Natural Science Foundation of Guangdong Province, the Science and Technology Plan Project of Guangzhou, Wenzhou Science & Technology Bureau, Guangdong Province Pearl River Scholar Fund, Guangdong province science and technology innovation leading Scholar Fund.

Combined intranasal nerve growth factor and ventricle neural stem cell grafts prolong survival and improve disease outcome in amyotrophic lateral sclerosis transgenic mice.

Amyotrophic lateral sclerosis (ALS) is a fatal disease that selectively involves motor neurons. Neurotrophic factor supplementation and neural stem cell (NSC) alternative therapy have been used to treat ALS. The two approaches can affect each other in their pathways of action, and there is a possibility for synergism. However, to date, there have been no studies demonstrating the effects of combined therapy in the treatment of ALS. In this study, for the first time, we adopted a method involving the intranasal administration of nerve growth factor combined with lateral ventricle NSC transplantation using G93A-SOD1 transgenic mice as experimental subjects to explore the treatment effect of this combined therapy in ALS. We discover that the combined therapy increase the quantity of TrkA receptors, broaden the migration of exogenous NSCs, further promote active proliferation in neurogenic regions of the brain and enhance the preservation of motor neurons in the spinal cord. Regarding physical activity, the combined therapy improved motor functions, further postponed ALS onset and extended the survival time of the mice.

Adjuvant neurotrophic factors in peripheral nerve repair with chondroitin sulfate proteoglycan-reduced acellular nerve allografts.

BACKGROUND: Acellular nerve allografts are now standard tools in peripheral nerve repair because of decreased donor site morbidity and operative time savings. Preparation of nerve allografts involves several steps of decellularization and modification of extracellular matrix to remove chondroitin sulfate proteoglycans (CSPGs), which have been shown to inhibit neurite outgrowth through a poorly understood mechanism involving RhoA and extracellular matrix-integrin interactions. Chondroitinase ABC (ChABC) is an enzyme that degrades CSPG molecules and has been shown to promote neurite outgrowth after injury of the central and peripheral nervous systems. Variable results after ChABC treatment make it difficult to predict the effects of this drug in human nerve allografts, especially in the presence of native extracellular signaling molecules. Several studies have shown cross-talk between neurotrophic factor and CSPG signaling pathways, but their interaction remains poorly understood. In this study, we examined the adjuvant effects of nerve growth factor (NGF) and glial cell line-derived neurotrophic factor (GDNF) on neurite outgrowth postinjury in CSPG-reduced substrates and acellular nerve allografts. MATERIALS AND METHODS: E12 chicken DRG explants were cultured in medium containing ChABC, ChABC + NGF, ChABC + GDNF, or control media. Explants were imaged at 3 d and neurite outgrowths measured. The rat sciatic nerve injury model involved a 1-cm sciatic nerve gap that was microsurgically repaired with ChABC-pretreated acellular nerve allografts. Before implantation, nerve allografts were incubated in NGF, GDNF, or sterile water. Nerve histology was evaluated at 5 d and 8 wk postinjury. RESULTS: The addition of GDNF in vitro produced significant increase in sensory neurite length at 3 d compared with ChABC alone (P < 0.01), whereas NGF was not significantly different from control. In vivo adjuvant NGF produced increases in total myelinated axon count (P < 0.005) and motor axon count (P < 0.01), whereas significantly reducing IB4+ nociceptor axon count (P < 0.01). There were no significant differences produced by in vivo adjuvant GDNF. CONCLUSIONS: This study provides initial evidence that CSPG-reduced nerve grafts may disinhibit the prosurvival effects of NGF in vivo, promoting motor axon outgrowth and reducing regeneration of specific nociceptive neurons. Our results support further investigation of adjuvant NGF therapy in CSPG-reduced acellular nerve grafts.

Rat cavernous nerve reconstruction with CD133+ cells derived from human bone marrow.

INTRODUCTION: Erectile dysfunction remains a major complication after surgery of pelvic organs, especially after radical prostatectomy. AIM: The aim of this study was to assess the effect of endothelial progenitor cells on the regeneration of cavernous nerves in a rat injury model. METHODS: A 2 mm length of the right and left cavernous nerves of 8-week-old male nude rats were excised. Alginate gel sponge sheets supplemented with 1 × 10(4) CD133+ cells derived from human bone marrow were then placed over the gaps on both sides (CD group). The same experiments were performed on sham-operated rats (SH group), rats with only the nerve excision (EX group), and rats with alginate gel sheets placed on the injured nerves (AL group). MAIN OUTCOME MEASURES: Immunofluorescence staining and molecular evaluation were performed 4 days later. Functional and histological evaluations were performed 12 weeks later. RESULTS: The intracavernous pressure elicited by electrical stimulation and the neuronal nitric oxide synthase-positive area in surrounding tissues of the prostate was significantly greater in the CD group. Immunofluorescence microscopy showed that CD133+ cells were assimilated as vascular endothelial cells, and the real-time polymerase chain reaction showed upregulation of nerve growth factor and vascular endothelial growth factor in the alginate gel sponge sheets of the CD group. CONCLUSIONS: Transplantation of CD133+ cells accelerated the functional and histological recovery in this cavernous nerve injury model, and the recovery mechanism is thought to be angiogenesis and upregulation of growth factors. CD133+ cells could be an optional treatment for cavernous nerve injury after prostatectomy in clinical settings.

Capsaicin-induced corneal sensory denervation and healing impairment are reversed by NGF treatment.

PURPOSE: We aimed to evaluate the nerve growth factor (NGF) pathway and its influence on corneal healing mechanisms in normal conditions and in an animal model of corneal denervation induced by capsaicin. METHODS: Peripheral sensory damage was induced in rat pups by subcutaneous injection of capsaicin and the effects evaluated by hot-plate test, corneal nerve count, and tear secretion. Corneal damage was induced in capsaicin-treated and -untreated rats by epithelial scraping. Healing rate; NGF pathway (NGF, tyrosine kinase A [TrkA], p75); and the stem cell marker p63 were evaluated by RT-PCR, ELISA, Western blot, and immunohistochemistry. The effects of exogenous NGF administration as eye drop formulation were also tested. RESULTS: Capsaicin treatment induced a significant reduction of peripheral sensitivity, corneal innervation, tear secretion, and corneal healing rate. The ocular effects of capsaicin treatment were associated with an NGF pathway alteration. NGF eye drop treatment aided corneal healing mechanisms through a significant increase in the NGF receptors TrkA and p75, and in the stem cell marker p63. CONCLUSIONS: In this study, we show that an alteration in the NGF pathway is responsible for a delay in corneal healing in an animal model of sensory denervation. Moreover, we show that NGF eye drop administration modulates corneal innervation, epithelial cell healing, and corneal stem cells. These findings may trigger further research on the role of the NGF pathway in limbal stem cell deficiency.

NGF protects dorsal root ganglion neurons from oxaliplatin by modulating JNK/Sapk and ERK1/2.

The involvement of the Mitogen-Activated Protein Kinases (MAPKs) family in platinum derivative-induced peripheral neuropathy has already been demonstrated. In particular, it has been evidenced that in Dorsal Root Ganglion (DRG) neurons prolonged exposure to oxaliplatin (OHP) induces early activation of p38 and ERK1/2, which mediate neuronal apoptosis, while the neuroprotective action of JNK/Sapk is downregulated by the drug treatment. In this study, the exposure of OHP-treated neurons to a neuroprotective stimulus, represented by a high dose of NGF, counteracts OHP-induced neuronal mortality. This effect was achieved by restoring the MAPK activation existing in untreated control cells. Increased viability occurred also after the administration of retinoic acid (RA), a pro-differentiative agent able to activate both JNK/Sapk and ERK1/2. The use of specific chemical inhibitors of MAPKs confirms the importance of this class of proteins for the neuroprotective pathway, since they reverse the protective effect. In summary, our findings assess the validity of MAPKs as the target of neuroprotective therapies during chemotherapeutic treatment. Moreover they also describe a double role for ERK1/2, depending on cellular stimulation, since it mediates neuronal apoptosis after OHP exposure. However, it is also important, as is JNK/Sapk, in preserving the correct cellular differentiation that is pivotal for neuronal survival.

Pharmacological treatment of painful HIV-associated sensory neuropathy: a systematic review and meta-analysis of randomised controlled trials.

BACKGROUND: Significant pain from HIV-associated sensory neuropathy (HIV-SN) affects ∼40% of HIV infected individuals treated with antiretroviral therapy (ART). The prevalence of HIV-SN has increased despite the more widespread use of ART. With the global HIV prevalence estimated at 33 million, and with infected individuals gaining increased access to ART, painful HIV-SN represents a large and expanding world health problem. There is an urgent need to develop effective pain management strategies for this condition. OBJECTIVE: To evaluate the clinical effectiveness of analgesics in treating painful HIV-SN. DESIGN: Systematic review and meta-analysis. DATA SOURCES: Medline, Cochrane central register of controlled trials, www.clinicaltrials.gov, www.controlled-trials.com and the reference lists of retrieved articles. SELECTION CRITERIA: Prospective, double-blinded, randomised controlled trials (RCTs) investigating the pharmacological treatment of painful HIV-SN with sufficient quality assessed using a modified Jadad scoring method. REVIEW METHODS: Four authors assessed the eligibility of articles for inclusion. Agreement of inclusion was reached by consensus and arbitration. Two authors conducted data extraction and analysis. Dichotomous outcome measures (≥ 30% and ≥ 50% pain reduction) were sought from RCTs reporting interventions with statistically significant efficacies greater than placebo. These data were used to calculate RR and NNT values. RESULTS: Of 44 studies identified, 19 were RCTs. Of these, 14 fulfilled the inclusion criteria. Interventions demonstrating greater efficacy than placebo were smoked cannabis NNT 3.38 95%CI(1.38 to 4.10), topical capsaicin 8%, and recombinant human nerve growth factor (rhNGF). No superiority over placebo was reported in RCTs that examined amitriptyline (100mg/day), gabapentin (2.4 g/day), pregabalin (1200 mg/day), prosaptide (16 mg/day), peptide-T (6 mg/day), acetyl-L-carnitine (1g/day), mexilitine (600 mg/day), lamotrigine (600 mg/day) and topical capsaicin (0.075% q.d.s.). CONCLUSIONS: Evidence of efficacy exists only for capsaicin 8%, smoked cannabis and rhNGF. However,rhNGF is clinically unavailable and smoked cannabis cannot be recommended as routine therapy. Evaluation of novel management strategies for painful HIV-SN is urgently needed.

[Effect of acupuncture-moxibustion combined with nerve growth factor on compensation of cerebral function in the children of cerebral palsy].

OBJECTIVE: To investigate the compensation of cerebral function in acupuncture for rehabilitation of cerebral palsy. METHODS: One hundred children of cerebral palsy were randomly divided into a treatment group and a control group, 50 cases in each group. The treatment group were treated with scalp acupuncture at the Motor Area, Foot Motor Sensory Area and Equilibrium Area, body acupuncture at Binao (LI 14), Fengchi (GB 20), Huantiao (GB 30), etc. and injection of nerve growth factor into Zusanli (ST 36), in combination with rehabilitation training; the control group were treated only with rehabilitation training. Their clinical therapeutic effects and recoveries of brain lesion detected by CT, SEPCT were investigated. RESULTS: The total effective rate was 84.0% in the treatment group better than 52.0% of the control group. After treatment, the development quotient (DQ) in the treatment group was higher than the control group (P<0.01). CONCLUSION: Acupuncture can promote compensation of cerebral function in the children of cerebral palsy.

Neurodegeneration from mitochondrial insufficiency: nutrients, stem cells, growth factors, and prospects for brain rebuilding using integrative management.

Degenerative brain disorders (neurodegeneration) can be frustrating for both conventional and alternative practitioners. A more comprehensive, integrative approach is urgently needed. One emerging focus for intervention is brain energetics. Specifically, mitochondrial insufficiency contributes to the etiopathology of many such disorders. Electron leakages inherent to mitochondrial energetics generate reactive oxygen free radical species that may place the ultimate limit on lifespan. Exogenous toxins, such as mercury and other environmental contaminants, exacerbate mitochondrial electron leakage, hastening their demise and that of their host cells. Studies of the brain in Alzheimer's and other dementias, Down syndrome, stroke, Parkinson's disease, multiple sclerosis, amyotrophic lateral sclerosis, Huntington's disease, Friedreich's ataxia, aging, and constitutive disorders demonstrate impairments of the mitochondrial citric acid cycle and oxidative phosphorylation (OXPHOS) enzymes. Imaging or metabolic assays frequently reveal energetic insufficiency and depleted energy reserve in brain tissue in situ. Orthomolecular nutrients involved in mitochondrial metabolism provide clinical benefit. Among these are the essential minerals and the B vitamin group; vitamins E and K; and the antioxidant and energetic cofactors alpha-lipoic acid (ALA), ubiquinone (coenzyme Q10; CoQ10), and nicotinamide adenine dinucleotide, reduced (NADH). Recent advances in the area of stem cells and growth factors encourage optimism regarding brain regeneration. The trophic nutrients acetyl L-carnitine (ALCAR), glycerophosphocholine (GPC), and phosphatidylserine (PS) provide mitochondrial support and conserve growth factor receptors; all three improved cognition in double-blind trials. The omega-3 fatty acid docosahexaenoic acid (DHA) is enzymatically combined with GPC and PS to form membrane phospholipids for nerve cell expansion. Practical recommendations are presented for integrating these safe and well-tolerated orthomolecular nutrients into a comprehensive dietary supplementation program for brain vitality and productive lifespan.

[Conservative and surgical treatment of neurotrophic keratopathy]. / Konservative und chirurgische Therapie der neurotrophen Keratopathie.

Neurotrophic keratopathy is one of the most challenging conditions among the disorders of wound healing of the ocular surface. In addition to bilateral assessment of corneal sensitivity, tear status and lid function must be analyzed and treated by unpreserved artificial tears and adequate lid surgery. Further conservative treatment options include hyaluronic acid and dexpanthenol as well as autologous serum. Application of recombinant growth factors (especially NGF) represents an interesting perspective. Concerning surgical interventions, temporary or permanent occlusion of the lacrimal punctum may be accompanied by lateral tarsorrhaphy which is easy to perform, potentially reversible, and in most cases successful. Depending on the type of wound healing disorder amniotic membrane transplantation may be helpful either as basal membrane transplant (graft) or as a patch, or in combination (sandwich). A tectonic keratoplasty a chaud should typically be combined with a simultaneous amniotic membrane patch and/or a lateral tarsorrhaphy to avoid persistent epithelial defects.

Nerve growth factor supplementation reverses the impairment, induced by Type 1 diabetes, of hindlimb post-ischaemic recovery in mice.

AIMS/HYPOTHESIS: Type 1 diabetes increases the risk of peripheral ischaemia and impairs recovery once ischaemia occurs, probably because the healing process is hampered by diabetes-induced endothelial dysfunction. In normoglycaemic mice subjected to limb ischaemia, blockade of nerve growth factor (NGF) compromises reparative angiogenesis. In the present study, we evaluated if expressional alterations of endogenous NGF system components are associated with diabetes-related impairment in neovascularisation. In addition, we tested whether the correction of NGF liabilities benefits post-ischaemic healing of Type 1 diabetic animals. METHODS: Unilateral hindlimb ischaemia was produced in streptozotocin-induced Type 1 diabetic mice. Purified murine NGF (20 microg daily for 14 days) or PBS were injected into ischaemic adductors. Non-diabetic mice given PBS served as controls. Hindlimb blood flow was analysed sequentially for up to 14 days. At necroscopy, adductors were removed for quantification of microvessel density, endothelial cell apoptosis and NGF receptor expression. NGF content was determined by ELISA three days after ischaemia. In vitro, we tested whether NGF protects endothelial cells from apoptosis induced by high glucose and whether vascular endothelial growth factor-A (VEGF-A) is involved in this beneficial effect. RESULTS: Muscles removed from Type 1 diabetic mice showed reduced NGF content and up-regulation of the NGF p75 receptor. NGF supplementation promoted capillarisation and arteriogenesis, reduced apoptosis, and accelerated blood flow recovery. NGF stimulated VEGF-A production by human endothelial cells incubated in high-glucose medium and conferred resistance against high-glucose-induced apoptosis via a VEGF-A-mediated mechanism. CONCLUSIONS/INTERPRETATION: NGF protects endothelial cells from apoptosis induced by Type 1 diabetes and facilitates reparative neovascularisation. The findings may open up new therapeutic options for the treatment of diabetic complications.

Nerve growth factor promotes reparative angiogenesis and inhibits endothelial apoptosis in cutaneous wounds of Type 1 diabetic mice.

AIMS/HYPOTHESIS: The neurotrophin nerve growth factor (NGF) is pro-angiogenic and facilitates wound repair. The present study was conducted to (i) assess the statement of NGF system components in diabetic wounds and (ii) evaluate whether NGF supplementation could prevent impairment of wound neoangiogenesis by diabetes. METHODS: Skin wounds were produced in the interscapular region of streptozotocin-induced diabetic mice. NGF (1 microg per day in PBS) or vehicle was applied onto the ulcers for 3 days after punching. Non-diabetic mice were used as controls. RESULTS: In wounds of untreated diabetic mice, endogenous levels of immunoreactive NGF were lower than those in wounds of non-diabetic mice ( p<0.01). Immunohistochemical analysis showed down-regulation of tyrosine kinase receptor-A (TrkA) and up-regulation of p75 receptor in granulation tissue microvasculature. Local NFG administration prevented diabetes-induced expressional alterations, enhanced reparative capillarisation ( p<0.01), and accelerated wound closure ( p<0.01). This was associated with a three-fold increase in endothelial cell proliferation ( p<0.01), while apoptosis was reduced by 50% ( p<0.05). Quantitative RT-PCR documented a 5.5-fold increase in the expression of vascular endothelial growth factor-A (VEGF-A) by exogenous NGF in diabetic tissues ( p<0.01). In in vitro preparations of human endothelial cells from derma, NGF increased the release of immunoreactive VEGF-A, and reduced high-glucose-induced apoptosis ( p<0.05), the latter effect being inhibited by a VEGF-A receptor-2 antagonist. CONCLUSIONS/INTERPRETATION: Diabetic ulcers display distinct alterations in reparative angiogenesis and in the expression of NGF and its receptors. NGF supplementation corrects endogenous liabilities, facilitates vascular regeneration, and suppresses endothelial apoptosis seemingly via VEGF-A. Our findings unravel new mechanisms responsible for NGF reparative action.

Nerve growth factor: from animal models of cholinergic neuronal degeneration to gene therapy in Alzheimer's disease.

Over the last 20 years it has been recognized that neurotrophic factors profoundly influence the development of the nervous system and have the potential to modify disease processes in the adult nervous system. The ability of nervous system growth factors to prevent or reduce neuronal degeneration in animal models of neurodegenerative diseases has led to several clinical trials. One of the main obstacles to the success of these trials has been the method of growth factor delivery: sufficiently high doses of neurotrophic factors must be achieved in the target region of the brain to efficiently modify disease processes, but delivery must be restricted to specific brain regions to prevent adverse effects. Recent advances in molecular medicine have made gene therapy in the nervous system a potentially realistic approach for the delivery of therapeutic molecules such as growth factors. As an alternative to conventional drug delivery, several gene therapy trials for the treatment of central nervous system diseases have started or will start in the near future. This chapter reviews the development of neurotrophic factor gene therapy for neurodegenerative diseases focusing on the therapeutic potential of nerve growth factor in Alzheimer's disease, currently the subject of a phase I clinical trial.

Influence of nerve growth factor upon the injured peripheral nerve in the absence of its distal part.

Transected peripheral nerve can be protected with different supplementations. One of them is implantation of dead-ended connective tissue chambers filled with fibrin and growth-promoting substances. The aim of this study was to find whether nerve growth factor (NGF) applied by means of such method exerts neuroprotective effect upon transected sciatic nerves. Study was performed on the adult male Wistar C rats. Connective tissue chambers grew around the silicone tubes implanted under their skin. Chambers were then filled with fibrin (control group) or fibrin with NGF solution (NGF group). Right sciatic nerve was cut, its distal stump was removed and its proximal stump was introduced into the chamber. Following 4 weeks DiI was applied to the free end of implant. The labeled motoneurons in the slices obtained from L3-L4 spinal cord segments and the number of myelinated nerve fibers present in the middle part of the chambers were counted. Acetylcholinesterase-positive fiber endings inside the chambers were also visualized. Our data showed that the number of motor neurons and their diameters as well as the number of myelinated fibers were higher in the NGF group when compared to the control group, but these differences were not significant. In both groups parallelly arranged acetylcholinesterase-positive nerve fibers were present. The obtained results show that NGF has no influence on regeneration of the motor component of the rat sciatic nerves in adult animals.

[Treatment of Alzheimer's disease]. / tratamiento de la enfermedad de Alzheimer.

OBJECTIVE: To review the experience of the last twenty years in the treatment of Alzheimer s disease (AD). METHODS: Literature review. RESULTS: The neuropathological bases of AD are centered on two important pathophysiological mechanisms: 1) Structural damage (e.g., senile plaques, neurofibrillary tangles, neuronal loss, inflammatory processes), and 2) Loss of cholinergic neurons (and acetylcholine depletion) in the nucleus basalis of Meynert, which sends cholinergic projections to all areas of the neocortex, especially the temporal lobes and frontal and parietal association areas. The indemnity of this system is essential for normal cognitive functioning. At this moment, the only long term treatment available for AD are acetylcholinesterase inhibitors (CEIs) (e.g., tacrine, donepezil, rivastigmine, galanthamine). There are being investigated several treatments that may alter the development of neurofibrillary tangles and neuritic plaques (e.g., peripherally administered antibodies against beta amyloid proteins). Nerve growth factors may have the capability of improving neuronal survival, although their form of administration remains a problem. Amelioration of oxidative stress and CNS inflammatory processes may slow dawn the rate of neurodegeneration. CONCLUSION: All suspected mechanisms of the metabolic cascade of AD have been explored with specific and non specific treatments. Current treatments (e.g., CEIs) still have to prove that their effects can last for long periods of time. With the advent of further understanding of the neurodegenerative processes that cause AD, new treatments that may slow down the progression of the disease will be available.

[Neurotrophin therapy. Some bioethical considerations]. / Terapia con neurotrofinas. Algunas consideraciones bioéticas.

Bioethics , which provides a new ethical outlook on human life, is a term used in public health and biomedical research issues. It is for this reason that, in this paper, we decided to analyse certain aspects associated with the ethical considerations we must bear in mind when conducting research in humans, although the purpose of doing so is to cure or to improve the quality of life of people who suffer from certain diseases, many of which are fatal. Reasons are put forward to make it necessary to doubt which is the strategy with the most favourable benefit/risk relation for those who will undergo such interventions. We describe Alzheimer s disease and discuss the possible use of neurotrophic drugs in the treatment of this disorder (NGF therapy). We also emphasise the care that will have to be taken in each of the stages of development of the research. That is why we are witnessing the emergence of a new culture that is needed to regulate the multiple interventions that can be performed on life, and to guarantee the primacy of what is good, both for the human being of today and those of generations to come.