RESUMO
BACKGROUND: Amyotrophic lateral sclerosis (ALS) is a neurodegenerative disease that results from a progressive loss of motor neurons. Familial ALS (fALS) is caused by missense mutations in Cu, Zn-superoxide dismutase 1 (SOD1) that frequently result in the accumulation of mutant protein aggregates that are associated with impairments in the ubiquitin-proteasome system (UPS). UPS impairment has been implicated in many neurological disorders. Bee venom (BV) extracted from honey bees has been used as a traditional medicine for treating inflammatory diseases and has been shown to attenuate the neuroinflammatory events that occur in a symptomatic ALS animal model. METHODS: NSC34 cells were transiently transfected with a WT or G85R hSOD1-GFP construct for 24 hrs and then stimulated with 2.5 µg/ml BV for 24 hrs. To determine whether a SOD1 mutation affects UPS function in NSC34 cells, we examined proteasome activity and performed western blotting and immunofluorescence using specific antibodies, such as anti-misfolded SOD1, anti-ubiquitin, anti-GRP78, anti-LC3, and anti-ISG15 antibodies. RESULTS: We found that GFP-hSOD1G85R overexpression induced SOD1 inclusions and reduced proteasome activity compared with the overexpression of GFP alone in NSC34 motor neuronal cells. In addition, we also observed that BV treatment restored proteasome activity and reduced the accumulation of ubiquitinated and misfolded SOD1 in GFP-hSOD1G85R-overexpressing NSC34 motor neuronal cells. However, BV treatment did not activate the autophagic pathway in these cells. CONCLUSION: Our findings suggest that BV may rescue the impairment of the UPS in ALS models.
Assuntos
Esclerose Lateral Amiotrófica/metabolismo , Venenos de Abelha/farmacologia , Abelhas , Neurônios Motores/efeitos dos fármacos , Complexo de Endopeptidases do Proteassoma/metabolismo , Superóxido Dismutase/metabolismo , Ubiquitina/metabolismo , Esclerose Lateral Amiotrófica/tratamento farmacológico , Animais , Apiterapia , Autofagia , Chaperona BiP do Retículo Endoplasmático , Humanos , Camundongos , Neurônios Motores/metabolismo , Mutação , Superóxido Dismutase/genética , Superóxido Dismutase-1 , TransfecçãoRESUMO
Bee venom (BV), which is extracted from honeybees, is used in traditional Korean medical therapy. Several groups have demonstrated the anti-inflammatory effects of BV in osteoarthritis both in vivo and in vitro. Glutamate is the predominant excitatory neurotransmitter in the central nervous system (CNS). Changes in glutamate release and uptake due to alterations in the activity of glutamate transporters have been reported in many neurodegenerative diseases, including Parkinson's disease, Alzheimer's disease, and amyotrophic lateral sclerosis. To assess if BV can prevent glutamate-mediated neurotoxicity, we examined cell viability and signal transduction in glutamate-treated neuronal and microglial cells in the presence and absence of BV. We induced glutamatergic toxicity in neuronal cells and microglial cells and found that BV protected against cell death. Furthermore, BV significantly inhibited the cellular toxicity of glutamate, and pretreatment with BV altered MAP kinase activation (e.g., JNK, ERK, and p38) following exposure to glutamate. These findings suggest that treatment with BV may be helpful in reducing glutamatergic cell toxicity in neurodegenerative diseases.
RESUMO
BACKGROUND: Because amyotrophic lateral sclerosis (ALS) is a progressive inflammatory disease, treatment of the pulmonary system plays a key role in ALS patients' care. Previous studies have mainly examined the pathological mechanism of ALS in the central nervous system; however, there has been relatively little research regarding the pulmonary system in ALS animal models. In inflammatory diseases, including asthma and arthritis, electroacupuncture (EA) is commonly used for its anti-inflammatory effects. The goal of this study was to determine whether EA treatment affects inflammation in the pulmonary system in an ALS animal model. METHODS: EA treatment at ST36 (Zusanli) acupoint was performed with 14-week-old hSOD1(G93A) transgenic mice. Immunohistochemical analysis was performed using anti-ionized calcium binding adaptor molecule 1 (Iba-1) and anti-tumor necrosis factor alpha (TNF-α) antibodies. To investigate the expression level of inflammatory proteins, Western blot analyses were performed using anti-Iba-1, anti-TNF-α, anti-nuclear factor kappa B (NF-κB), and anti-interleukin 6 (IL-6) antibodies. The activation of Ser435-phospho-specific RAC-alpha serine/threonine-protein kinase 1 (pAKT) and the increase of phosphorylated extracellular-signal-regulated kinases (pERK) protein in lung tissues of EA-treated and untreated hSOD1(G93A) mice were also evaluated by Western blot. RESULTS: EA treatment decreased the expression of the proinflammatory proteins such as TNF-α and IL-6, pNF-κB, and Iba-1 and increased the level of activated pAKT and pERK compared to control hSOD1(G93A) mice. CONCLUSIONS: Our findings suggest that EA could be an effective anti-inflammatory treatment for the respiratory impairment that occurs in ALS animal models.
Assuntos
Esclerose Lateral Amiotrófica/complicações , Eletroacupuntura , Inflamação/terapia , Doenças Respiratórias/etiologia , Doenças Respiratórias/terapia , Proteínas Adaptadoras de Transdução de Sinal/biossíntese , Esclerose Lateral Amiotrófica/patologia , Animais , Western Blotting , Contagem de Células , Sobrevivência Celular/fisiologia , Proteínas do Citoesqueleto/biossíntese , MAP Quinases Reguladas por Sinal Extracelular/biossíntese , Feminino , Imuno-Histoquímica , Interleucina-6/biossíntese , Pulmão/metabolismo , Masculino , Camundongos , Camundongos Transgênicos , NF-kappa B/biossíntese , Proteínas Nucleares/biossíntese , Proteína Oncogênica v-akt/biossíntese , Doenças Respiratórias/patologia , Superóxido Dismutase/genética , Superóxido Dismutase/metabolismo , Superóxido Dismutase-1 , Fator de Necrose Tumoral alfa/biossíntese , Proteínas rac de Ligação ao GTP/biossínteseRESUMO
Amyotrophic lateral sclerosis (ALS) is a paralyzing disorder characterized by the progressive degeneration and death of motor neurons and occurs both as a sporadic and familial disease. Mutant SOD1 (mtSOD1) in motor neurons induces vulnerability to the disease through protein misfolding, mitochondrial dysfunction, oxidative damage, cytoskeletal abnormalities, defective axonal transport- and growth factor signaling, excitotoxicity, and neuro-inflammation.Melittin is a 26 amino acid protein and is one of the components of bee venom which is used in traditional Chinese medicine to inhibit of cancer cell proliferation and is known to have anti-inflammatory and anti-arthritic effects.The purpose of the present study was to determine if melittin could suppress motor neuron loss and protein misfolding in the hSOD1G93A mouse, which is commonly used as a model for inherited ALS. Meltittin was injected at the 'ZuSanLi' (ST36) acupuncture point in the hSOD1G93A animal model. Melittin-treated animals showed a decrease in the number of microglia and in the expression level of phospho-p38 in the spinal cord and brainstem. Interestingly, melittin treatment in symptomatic ALS animals improved motor function and reduced the level of neuron death in the spinal cord when compared to the control group. Furthermore, we found increased of α-synuclein modifications, such as phosphorylation or nitration, in both the brainstem and spinal cord in hSOD1G93A mice. However, melittin treatment reduced α-synuclein misfolding and restored the proteasomal activity in the brainstem and spinal cord of symptomatic hSOD1G93A transgenic mice.Our research suggests a potential functional link between melittin and the inhibition of neuroinflammation in an ALS animal model.