RESUMEN
The transient receptor potential canonical 6 (TRPC6) channel, a nonselective cation channel that allows the passage of Ca2+, plays an important role in renal diseases. TRPC6 is activated by Ca2+ influx, oxidative stress, and mechanical stress. Studies have shown that in addition to glomerular diseases, TRPC6 can contribute to renal tubular disorders, such as acute kidney injury, renal interstitial fibrosis, and renal cell carcinoma (RCC). However, the tubule-specific physiological functions of TRPC6 have not yet been elucidated. Its pathophysiological role in ischemia/reperfusion (I/R) injury is debatable. Thus, TRPC6 may have dual roles in I/R injury. TRPC6 induces renal fibrosis and immune cell infiltration in a unilateral ureteral obstruction (UUO) mouse model. Additionally, TRPC6 overexpression may modify G2 phase transition, thus altering the DNA damage checkpoint, which can cause genomic instability and RCC tumorigenesis and can control the proliferation of RCC cells. This review highlights the importance of TRPC6 in various conditions of the renal tubular system. To better understand certain renal disorders and ultimately identify new therapeutic targets to improve patient care, the pathophysiology of TRPC6 must be clarified.
Asunto(s)
Canal Catiónico TRPC6 , Humanos , Canal Catiónico TRPC6/metabolismo , Canal Catiónico TRPC6/genética , Animales , Túbulos Renales/patología , Túbulos Renales/metabolismo , Lesión Renal Aguda/metabolismo , Lesión Renal Aguda/etiología , Carcinoma de Células Renales/metabolismo , Carcinoma de Células Renales/genética , Carcinoma de Células Renales/patología , Daño por Reperfusión/metabolismo , Fibrosis , Neoplasias Renales/metabolismo , Neoplasias Renales/patología , Neoplasias Renales/genética , Ratones , Canales Catiónicos TRPC/metabolismo , Canales Catiónicos TRPC/genética , Estrés Oxidativo , Enfermedades Renales/metabolismo , Enfermedades Renales/etiologíaRESUMEN
Transient receptor potential canonical (TRPC) channels are calcium channels with diverse expression profiles and physiological implications in the retina. Neurons and glial cells of rat retinas with photoreceptor degeneration caused by retinitis pigmentosa (RP) exhibit basal calcium levels that are above those detected in healthy retinas. Inner retinal cells are the last to degenerate and are responsible for maintaining the activity of the visual cortex, even after complete loss of photoreceptors. We considered the possibility that TRPC1 and TRPC5 channels might be associated with both the high calcium levels and the delay in inner retinal degeneration. TRPC1 is known to mediate protective effects in neurodegenerative processes while TRPC5 promotes cell death. In order to comprehend the implications of these channels in RP, the co-localization and subsequent physical interaction between TRPC1 and TRPC5 in healthy retina (Sprague-Dawley rats) and degenerating (P23H-1, a model of RP) retina were detected by immunofluorescence and proximity ligation assays. There was an overlapping signal in the innermost retina of all animals where TRPC1 and TRPC5 physically interacted. This interaction increased significantly as photoreceptor loss progressed. Both channels function as TRPC1/5 heteromers in the healthy and damaged retina, with a marked function of TRPC1 in response to retinal degenerative mechanisms. Furthermore, our findings support that TRPC5 channels also function in partnership with STIM1 in Müller and retinal ganglion cells. These results suggest that an increase in TRPC1/5 heteromers may contribute to the slowing of the degeneration of the inner retina during the outer retinal degeneration.
Asunto(s)
Ratas Sprague-Dawley , Degeneración Retiniana , Canales Catiónicos TRPC , Animales , Canales Catiónicos TRPC/metabolismo , Ratas , Degeneración Retiniana/metabolismo , Degeneración Retiniana/patología , Retina/metabolismo , Retina/patología , Células Fotorreceptoras de Vertebrados/metabolismo , Células Fotorreceptoras de Vertebrados/patología , Retinitis Pigmentosa/metabolismo , Retinitis Pigmentosa/patología , Retinitis Pigmentosa/genética , Modelos Animales de EnfermedadRESUMEN
Hypothalamic neural circuits regulate instinctive behaviors such as food seeking, the fight/flight response, socialization, and maternal care. Here, we identified microdeletions on chromosome Xq23 disrupting the brain-expressed transient receptor potential (TRP) channel 5 (TRPC5). This family of channels detects sensory stimuli and converts them into electrical signals interpretable by the brain. Male TRPC5 deletion carriers exhibited food seeking, obesity, anxiety, and autism, which were recapitulated in knockin male mice harboring a human loss-of-function TRPC5 mutation. Women carrying TRPC5 deletions had severe postpartum depression. As mothers, female knockin mice exhibited anhedonia and depression-like behavior with impaired care of offspring. Deletion of Trpc5 from oxytocin neurons in the hypothalamic paraventricular nucleus caused obesity in both sexes and postpartum depressive behavior in females, while Trpc5 overexpression in oxytocin neurons in knock-in mice reversed these phenotypes. We demonstrate that TRPC5 plays a pivotal role in mediating innate human behaviors fundamental to survival, including food seeking and maternal care.
Asunto(s)
Depresión Posparto , Neuronas , Obesidad , Canales Catiónicos TRPC , Animales , Femenino , Ratones , Obesidad/metabolismo , Obesidad/genética , Masculino , Humanos , Canales Catiónicos TRPC/metabolismo , Canales Catiónicos TRPC/genética , Depresión Posparto/metabolismo , Neuronas/metabolismo , Núcleo Hipotalámico Paraventricular/metabolismo , Ratones Endogámicos C57BL , Oxitocina/metabolismo , Conducta MaternaRESUMEN
Zika virus (ZIKV) infection may lead to severe neurological consequences, including seizures, and early infancy death. However, the involved mechanisms are still largely unknown. TRPC channels play an important role in regulating nervous system excitability and are implicated in seizure development. We investigated whether TRPCs might be involved in the pathogenesis of ZIKV infection. We found that ZIKV infection increases TRPC4 expression in host cells via the interaction between the ZIKV-NS3 protein and CaMKII, enhancing TRPC4-mediated calcium influx. Pharmacological inhibition of CaMKII decreased both pCREB and TRPC4 protein levels, whereas the suppression of either TRPC4 or CaMKII improved the survival rate of ZIKV-infected cells and reduced viral protein production, likely by impeding the replication phase of the viral life cycle. TRPC4 or CaMKII inhibitors also reduced seizures and increased the survival of ZIKV-infected neonatal mice and blocked the spread of ZIKV in brain organoids derived from human-induced pluripotent stem cells. These findings suggest that targeting CaMKII or TRPC4 may offer a promising approach for developing novel anti-ZIKV therapies, capable of preventing ZIKV-associated seizures and death.
Asunto(s)
Proteína Quinasa Tipo 2 Dependiente de Calcio Calmodulina , Canales Catiónicos TRPC , Infección por el Virus Zika , Virus Zika , Infección por el Virus Zika/virología , Infección por el Virus Zika/metabolismo , Animales , Humanos , Virus Zika/fisiología , Virus Zika/efectos de los fármacos , Ratones , Canales Catiónicos TRPC/metabolismo , Canales Catiónicos TRPC/antagonistas & inhibidores , Proteína Quinasa Tipo 2 Dependiente de Calcio Calmodulina/metabolismo , Proteína Quinasa Tipo 2 Dependiente de Calcio Calmodulina/antagonistas & inhibidores , Replicación Viral/efectos de los fármacos , Células HEK293 , Proteínas Virales/metabolismo , Convulsiones/virología , Convulsiones/metabolismo , Convulsiones/tratamiento farmacológico , Proteasas Virales , Serina Endopeptidasas , Nucleósido-Trifosfatasa , ARN Helicasas DEAD-boxRESUMEN
BACKGROUND: Expression and function of TRPC3 and TRPC6 in the pancreas is a controversial topic. Investigation in human tissue is seldom. We aimed to provide here a detailed description of the distribution of TRPC3 and TRPC6 in the human exocrine and endocrine pancreas. METHODS: We collected healthy samples from cadavers (n = 4) and visceral surgery (n = 4) to investigate the respective expression profiles using immunohistochemical tracing with knockout-validated antibodies. RESULTS: TRPC3- and TRPC6-proteins were detected in different pancreatic structures including acinar cells, as well as epithelial ductal cells from intercalate, intralobular, and interlobular ducts. Respective connective tissue layers appeared unstained. Endocrine islets of Langerhans were clearly and homogenously immunolabeled by the anti-TRPC3 and anti-TRPC6 antibodies. Insular α, ß, γ, and δ cells were conclusively stained, although no secure differentiation of cell types was performed. CONCLUSIONS: Due to aforementioned antibody specificity verification, protein expression in the immunolabeled localizations can be accepted. Our study in human tissue supports previous investigations especially with respect to acinar and insular α and ß cells, while other localizations are here reported for the first time to express TRPC3 and TRPC6, ultimately warranting further research.
Asunto(s)
Páncreas Exocrino , Canales Catiónicos TRPC , Canal Catiónico TRPC6 , Humanos , Canales Catiónicos TRPC/metabolismo , Canal Catiónico TRPC6/metabolismo , Páncreas Exocrino/metabolismo , Islotes Pancreáticos/metabolismo , Masculino , Femenino , Persona de Mediana Edad , Anciano , Adulto , InmunohistoquímicaRESUMEN
Transient receptor potential canonical 3 (TRPC3) channels are important in regulating Ca2+ homeostasis and have been implicated in the pathophysiology of chemically induced seizures. Inherited seizure susceptibility in genetically epilepsy-prone rats (GEPR-3s) has been linked to increased voltage-gated Ca2+ channel currents in the inferior colliculus neurons, which can affect intraneuronal Ca2+ homeostasis. However, whether TRPC3 channels also contribute to inherited seizure susceptibility in GEPR-3s is unclear. This study investigated the effects of JW-65, a potent and selective inhibitor of TRPC3 channels, on acoustically evoked seizure susceptibility in adult male and female GEPR-3s. These seizures consisted of wild running seizures (WRSs) that evolved into generalized tonic-clonic seizures (GTCSs). The results showed that acute administration of low doses of JW-65 significantly decreased by 55-89% the occurrence of WRSs and GTCSs and the seizure severity in both male and female GEPR-3s. This antiseizure effect was accompanied by increased seizure latency and decreased seizure duration. Additionally, female GEPR-3s were more responsive to JW-65's antiseizure effects than males. Moreover, JW-65 treatment for five consecutive days completely suppressed acoustically evoked seizures in male and female GEPR-3s. These findings suggest that inhibiting TRPC3 channels could be a promising antiseizure strategy targeting Ca2+ signaling mechanisms in inherited generalized tonic-clonic epilepsy.
Asunto(s)
Convulsiones , Canales Catiónicos TRPC , Animales , Masculino , Femenino , Convulsiones/fisiopatología , Convulsiones/genética , Convulsiones/inducido químicamente , Ratas , Canales Catiónicos TRPC/antagonistas & inhibidores , Canales Catiónicos TRPC/genética , Anticonvulsivantes/farmacología , Anticonvulsivantes/uso terapéutico , Predisposición Genética a la Enfermedad , Epilepsia/fisiopatología , Epilepsia/genética , Epilepsia/inducido químicamente , Epilepsia/tratamiento farmacológicoRESUMEN
Canonical transient receptor potential channel 3 (TRPC3) is the most abundant TRPC channel in the brain and is highly expressed in all subfields of the hippocampus. Previous studies have suggested that TRPC3 channels may be involved in the hyperexcitability of hippocampal pyramidal neurons and seizures. Genetic ablation of TRPC3 channel expression reduced the intensity of pilocarpine-induced status epilepticus (SE). However, the underlying cellular mechanisms remain unexplored and the contribution of TRPC3 channels to SE-induced neurodegeneration is not determined. In this study, we investigated the contribution of TRPC3 channels to the electrophysiological properties of hippocampal pyramidal neurons and hippocampal synaptic plasticity, and the contribution of TRPC3 channels to seizure-induced neuronal cell death. We found that genetic ablation of TRPC3 expression did not alter basic electrophysiological properties of hippocampal pyramidal neurons and had a complex impact on epileptiform bursting in CA3. However, TRPC3 channels contribute significantly to long-term potentiation in CA1 and SE-induced neurodegeneration. Our results provided further support for therapeutic potential of TRPC3 inhibitors and raised new questions that need to be answered by future studies.
Asunto(s)
Muerte Celular , Hipocampo , Células Piramidales , Convulsiones , Canales Catiónicos TRPC , Animales , Canales Catiónicos TRPC/metabolismo , Canales Catiónicos TRPC/genética , Ratones , Células Piramidales/metabolismo , Células Piramidales/patología , Hipocampo/metabolismo , Hipocampo/patología , Convulsiones/metabolismo , Convulsiones/patología , Estado Epiléptico/metabolismo , Estado Epiléptico/patología , Estado Epiléptico/inducido químicamente , Masculino , Neuronas/metabolismo , Pilocarpina , Potenciación a Largo Plazo , Ratones Noqueados , Ratones Endogámicos C57BL , Plasticidad NeuronalRESUMEN
OBJECTIVES: To observe the effect of electroacupuncture (EA) at "Neiguan"(PC6) on cardiac function, cardiac morphology and transient receptor potential channel (TRPC) protein expressions in myocardial tissue of mice with myocardial hypertrophy, so as to explore its mechanisms underlying improvement of myocardial hypertrophy. METHODS: Forty-five male C57BL/6 mice were randomly divided into control, model and EA groups (15 mice/group). The myocardial hypertrophy model was established by subcutaneous injection of isoproterenol hydrochloride (15 mg·kg-1·d-1) for 14 days. The mice of the control group received subcutaneous injection of same amount of normal saline. The mice of the EA group received EA stimulation (frequency of 2 Hz, intensity of 1 mA) of bilateral PC6 for 20 min each time, once a day for 14 consecutive days. After the intervention, the body weight, tibia length and heart weight were measured. The left ventricular ejection fraction (EF), fractional shortening index (FS), left ventricular end-systolic volume (LVEV), left ventricular end-systolic internal diameter (LVID) and left ventricular posterior wall thickness (LVPW) were measured by using echocardiography for evaluating the cardiac function. The mean number and surface area of myocardial cells was detected by wheat germ agglutinin (WGA) staining, and changes of the cardiac morphology were observed under light microscopy after HE staining. The expression levels of TRPC1, TRPC3, TRPC4 and TRPC6 (TRPC1/3/4/6) in the myocardial tissue were detected by real-time quantitative PCR (qPCR) and Western blot, separately. RESULTS: Compared with the control group, the heart-body weight ratio(P<0.05) and heart-weight-to-tibia-length ratio (P<0.01), LVEV and LVID levels, the relative surface area, left ventricular area ratio, and the expression levels of cardiac TRPC1/3/4/6 were significantly increased (P<0.01, P<0.05), while the EF, FS, LVPW, number of cardiomyocytes, and the left ventricular posterior wall ratio were obviously decreased (P<0.01, P<0.05) in the model group. In comparison with the model group, the heart/body weight ratio, heart-weight-to-tibia-length ratio, LVEV and LVID levels, relative surface area, left ventricular area ratio, and the expression levels of cardiac TRPC1/3/4/6 were significantly decreased (P<0.01, P<0.05), while the EF, FS, LVPW, number of cardiomyocytes and left ventricular posterior wall ratio were significantly increased (P<0.01, P<0.05) in the EA group. H.E. staining showed disordered arrangement of cardiomyocytes and obvious myocardial interstitial inflammatory cell infiltration in the model group, and evident reduction of degree of cardiac fibrosis and interstitial edema in the EA group. CONCLUSIONS: EA of PC6 can improve the cardiac function and cardiac morphology in mice with myocardial hypertrophy, which may be related to its functions in down-regulating the expression of transient receptor potential channels.
Asunto(s)
Electroacupuntura , Ratones Endogámicos C57BL , Miocardio , Animales , Ratones , Masculino , Humanos , Miocardio/metabolismo , Canales de Potencial de Receptor Transitorio/metabolismo , Canales de Potencial de Receptor Transitorio/genética , Cardiomegalia/metabolismo , Cardiomegalia/terapia , Cardiomegalia/genética , Cardiomegalia/fisiopatología , Puntos de Acupuntura , Canales Catiónicos TRPC/metabolismo , Canales Catiónicos TRPC/genéticaRESUMEN
OBJECTIVE: The continuously increasing extracellular matrix stiffness during intervertebral disc degeneration promotes disease progression. In an attempt to obtain novel treatment methods, this study aims to investigate the changes in nucleus pulposus cells under the stimulation of a stiff microenvironment. DESIGN: RNA sequencing and metabolomics experiments were combined to evaluate the primary nucleus pulposus and screen key targets under mechanical biological stimulation. Additionally, small molecules work in vitro were used to confirm the target regulatory effect and investigate the mechanism. In vivo, treatment effects were validated using a rat caudal vertebrae compression model. RESULTS: Our research results revealed that by activating TRPC6, hyperforin, a herbaceous extract can rescue the inflammatory phenotype caused by the stiff microenvironment, hence reducing intervertebral disc degeneration (IDD). Mechanically, it activates mitochondrial fission to inhibit PFKFB3. CONCLUSION: In summary, this study reveals the important bridging role of TRPC6 between mechanical stiffness, metabolism, and inflammation in the context of nucleus pulposus degeneration. TRPC6 activation with hyperforin may become a promising treatment for IDD.
Asunto(s)
Matriz Extracelular , Degeneración del Disco Intervertebral , Dinámicas Mitocondriales , Núcleo Pulposo , Floroglucinol , Ratas Sprague-Dawley , Animales , Núcleo Pulposo/metabolismo , Núcleo Pulposo/patología , Núcleo Pulposo/efectos de los fármacos , Degeneración del Disco Intervertebral/tratamiento farmacológico , Degeneración del Disco Intervertebral/patología , Degeneración del Disco Intervertebral/metabolismo , Ratas , Floroglucinol/farmacología , Floroglucinol/análogos & derivados , Floroglucinol/uso terapéutico , Dinámicas Mitocondriales/efectos de los fármacos , Matriz Extracelular/metabolismo , Matriz Extracelular/efectos de los fármacos , Masculino , Células Cultivadas , Humanos , Terpenos/farmacología , Terpenos/uso terapéutico , Canales Catiónicos TRPC/metabolismo , Modelos Animales de Enfermedad , Inflamación/tratamiento farmacológicoRESUMEN
The transient receptor potential canonical type 3 (TRPC3) channel plays a pivotal role in regulating neuronal excitability in the brain via its constitutive activity. The channel is intricately regulated by lipids and has previously been demonstrated to be positively modulated by PIP2. Using molecular dynamics simulations and patch clamp techniques, we reveal that PIP2 predominantly interacts with TRPC3 at the L3 lipid binding site, located at the intersection of pre-S1 and S1 helices. We demonstrate that PIP2 sensing involves a multistep mechanism that propagates from L3 to the pore domain via a salt bridge between the TRP helix and S4-S5 linker. Notably, we find that both stimulated and constitutive TRPC3 activity require PIP2. These structural insights into the function of TRPC3 are invaluable for understanding the role of the TRPC subfamily in health and disease, in particular for cardiovascular diseases, in which TRPC3 channels play a major role.
Asunto(s)
Simulación de Dinámica Molecular , Fosfatidilinositol 4,5-Difosfato , Canales Catiónicos TRPC , Canales Catiónicos TRPC/metabolismo , Canales Catiónicos TRPC/química , Canales Catiónicos TRPC/genética , Humanos , Fosfatidilinositol 4,5-Difosfato/metabolismo , Células HEK293 , Sitios de Unión , Animales , Técnicas de Placa-Clamp , Unión ProteicaRESUMEN
Transient receptor potential canonical 5 (TRPC5) is a calcium-permeable non-selective cation channel involved in various pathophysiological processes, including renal injury. Recently, GFB-887, an investigational pyridazinone TRPC5 inhibitor, demonstrated significant therapeutic potential in a Phase II clinical trial for focal segmental glomerulosclerosis (FSGS), a rare and severe form of chronic kidney disease (CKD). In the current study, based on the structure of GFB-887, we conducted extensive structural modification to explore novel TRPC5 inhibitors with desirable drug-like properties and robust nephroprotective efficacy. A series of pyridazinone derivatives featuring a novel tetrahydroimidazo[1,2-a]pyrazine scaffold were synthesized and their activities were evaluated in HEK-293 cells stably expressing TRPC5 using a fluorescence-based Ca2+ mobilization assay. Among these compounds, compound 12 is turned out to be a potent TRPC5 inhibitor with apparent affinity comparable to the parent compound GBF-887. Compound 12 is highly selective on TRPC4/5 over TRPC3/6/7 and hERG channels, along with acceptable pharmacokinetic properties and a favorable safety profile. More importantly, in a rat model of hypertension-induced renal injury, oral administration of compound 12 (10 mg/kg, BID) efficaciously reduced mean blood pressure, inhibited proteinuria, and protected podocyte damage. These findings further confirmed the potential of TRPC5 inhibitors on the CKD treatment and provided compound 12 to be a valuable tool for exploring TRPC4/5 pathophysiology.
Asunto(s)
Hipertensión , Pirazinas , Canales Catiónicos TRPC , Animales , Humanos , Ratas , Pirazinas/química , Pirazinas/farmacología , Pirazinas/síntesis química , Canales Catiónicos TRPC/antagonistas & inhibidores , Canales Catiónicos TRPC/metabolismo , Células HEK293 , Relación Estructura-Actividad , Masculino , Hipertensión/tratamiento farmacológico , Descubrimiento de Drogas , Estructura Molecular , Piridazinas/farmacología , Piridazinas/química , Piridazinas/síntesis química , Relación Dosis-Respuesta a Droga , Antihipertensivos/farmacología , Antihipertensivos/química , Antihipertensivos/síntesis química , Ratas Sprague-Dawley , Imidazoles/química , Imidazoles/farmacología , Imidazoles/síntesis químicaRESUMEN
Metabolic syndrome has become a global epidemic, affecting all developed countries and communities with growing economies. Worldwide, increasing efforts have been directed at curbing this growing problem. Mice deleted of the gene encoding Type 1 Transient Receptor Potential Canonical Channel (Trpc1) were found to weigh heavier than controls. They had fasting hyperglycemia and impaired glucose tolerance compared with wild-type controls. Beyond 1â year of age, plasma triglyceride level in Trpc1-/- mice was elevated. Plasma cholesterol levels tended to be higher than in controls. The livers of Trpc1-/- mice were heavier, richer in triglyceride, and more echogenic than those of controls on ultrasound evaluation. Hematocrit was lower in Trpc1-/- mice of both genders beginning at the second to third months of age in the absence of bleeding or hemolysis. Measured by the indirect tail-cuff method or by the direct arterial cannulation, blood pressures in null mice were lower than controls. We conclude that TRPC1 gene regulates body metabolism and that except for hypertension, phenotypes of mice after deletion of the Trpc1 gene resemble mice with metabolic syndrome, suggesting that this could be a good experimental model for future investigation of the pathogenesis and management of this disorder.
Asunto(s)
Síndrome Metabólico , Canales Catiónicos TRPC , Animales , Femenino , Masculino , Ratones , Presión Sanguínea , Modelos Animales de Enfermedad , Síndrome Metabólico/etiología , Síndrome Metabólico/metabolismo , Síndrome Metabólico/genética , Ratones Noqueados , Fenotipo , Canales Catiónicos TRPC/genética , Canales Catiónicos TRPC/metabolismo , Canales Catiónicos TRPC/deficienciaRESUMEN
BACKGROUND Obstructive sleep apnea-hypopnea syndrome (OSAHS) presents a significant health concern, particularly among individuals with essential hypertension (EH). Understanding the genetic underpinnings of this association is crucial for effective management and intervention. We investigated the relationship between TRPC3 gene polymorphisms and susceptibility to OSAHS in patients with EH. MATERIAL AND METHODS We enrolled 373 patients with EH hospitalized at the First Affiliated Hospital of Xinjiang Medical University between April 2015 and November 2017. Patients were categorized into EH (n=74) and EH+OSAHS (n=299) groups according to the apnea-hypopnea index. Sequenom detection technology was used for TRPC3 gene single-nucleotide polymorphism genotyping, including genotypes at rs953691, rs10518289, rs2292232, rs4995894, rs951974, and rs4292355. RESULTS Sex, smoking history, alcohol history, hypertension duration, fasting blood glucose, urea, creatinine, total cholesterol, HDL-C, LDL-C, glycosylated hemoglobin, 24-h mean systolic BP, and 24-h mean diastolic BP were not significantly different between the 2 groups (P>0.05); however, age, BMI, triglyceride levels differed significantly (P<0.05). No significant difference was detected in distribution frequency of polymorphisms of TRPC3 gene between the 2 groups (P>0.05), while genotype, dominant genotype, and recessive genotype at rs10518289 and alleles at rs4292355 differed significantly (P<0.05). Logistic regression analysis showed age, BMI, and CG+GG genotypes at rs10518289 were risk factors for OSAHS in patients with EH. Interaction between TRPC3 (rs10518289) and obesity was not a risk of OSAHS with EH (P>0.05). CONCLUSIONS CC genotype of rs10518289 in the TRPC3 gene could be a protective genetic marker of OSAHS, and CG+GG genotype may be a risk genetic marker of OSAHS with EH.
Asunto(s)
Predisposición Genética a la Enfermedad , Genotipo , Hipertensión , Polimorfismo de Nucleótido Simple , Apnea Obstructiva del Sueño , Canales Catiónicos TRPC , Humanos , Femenino , Masculino , Persona de Mediana Edad , Apnea Obstructiva del Sueño/genética , Polimorfismo de Nucleótido Simple/genética , Hipertensión/genética , Canales Catiónicos TRPC/genética , Anciano , China , Factores de Riesgo , Adulto , Alelos , Hipertensión Esencial/genéticaRESUMEN
Podocyte injury plays a vital role in focal segmental glomerulosclerosis (FSGS), and apoptosis is one of its mechanisms. The transient receptor potential channel 6 (TRPC6) is highly expressed in podocytes and mutations mediate podocyte injury. We found TRPC6 gene mutation (N110S) was a new mutation and pathogenic in the preliminary clinical work. The purpose of this study was to investigate the potential mechanism of mutation in TRPC6 (TRPC6-N110S) in the knock-in gene mouse model and in immortalized mouse podocytes (MPC5). Transmission electron microscopy was used to evaluate renal injury morphology. We measured 24-hour urinary albumin-to-creatinine ratios and major biochemical parameters such as serum albumin, urea nitrogen, and total cholesterol. The results of CCK-8 assay and apoptosis experiments showed that the TRPC6-N110S overexpression group had slower proliferative activity and increased apoptosis than the control group. FluO-3 assay revealed increased calcium influx in the TRPC6-N110S overexpression group. Podocin level was decreased in TRPC6-N110S group, while TRPC6 and desmin levels were increased in TRPC6-N110S group. The 24 h uACR at 6 weeks was significantly higher in the pure-zygotes group than in the WT and heterozygotes groups, and this difference was found at 8 and 10 weeks.TRPC6 levels showed no significant difference between homozygote and WT mice. Compared to homozygote group, expression of podocin and nephrin were increased in WT, but levels of desmin was decreased in WT. Our results suggest that this new mutation causes podocyte injury probably by enhancing calcium influx and podocyte apoptosis, accompanied by increased proteinuria and decreased expression of nephrin and podocin.
Asunto(s)
Apoptosis , Mutación con Ganancia de Función , Podocitos , Canal Catiónico TRPC6 , Podocitos/metabolismo , Podocitos/patología , Animales , Canal Catiónico TRPC6/genética , Canal Catiónico TRPC6/metabolismo , Apoptosis/genética , Ratones , Mutación con Ganancia de Función/genética , Calcio/metabolismo , Glomeruloesclerosis Focal y Segmentaria/genética , Glomeruloesclerosis Focal y Segmentaria/metabolismo , Glomeruloesclerosis Focal y Segmentaria/patología , Proteínas de la Membrana/genética , Proteínas de la Membrana/metabolismo , Desmina/genética , Desmina/metabolismo , Proliferación Celular/genética , Péptidos y Proteínas de Señalización Intracelular/genética , Péptidos y Proteínas de Señalización Intracelular/metabolismo , Canales Catiónicos TRPC/genética , Canales Catiónicos TRPC/metabolismo , Masculino , Ratones Endogámicos C57BLRESUMEN
In calcium nephrolithiasis (CaNL), most calcium kidney stones are identified as calcium oxalate (CaOx) with variable amounts of calcium phosphate (CaP), where CaP is found as the core component. The nucleation of CaP could be the first step of CaP+CaOx (mixed) stone formation. High urinary supersaturation of CaP due to hypercalciuria and an elevated urine pH have been described as the two main factors in the nucleation of CaP crystals. Our previous in vivo findings (in mice) show that transient receptor potential canonical type 3 (TRPC3)-mediated Ca2+ entry triggers a transepithelial Ca2+ flux to regulate proximal tubular (PT) luminal [Ca2+], and TRPC3-knockout (KO; -/-) mice exhibited moderate hypercalciuria and microcrystal formation at the loop of Henle (LOH). Therefore, we utilized TRPC3 KO mice and exposed them to both hypercalciuric [2% calcium gluconate (CaG) treatment] and alkalineuric conditions [0.08% acetazolamide (ACZ) treatment] to generate a CaNL phenotype. Our results revealed a significant CaP and mixed crystal formation in those treated KO mice (KOT) compared to their WT counterparts (WTT). Importantly, prolonged exposure to CaG and ACZ resulted in a further increase in crystal size for both treated groups (WTT and KOT), but the KOT mice crystal sizes were markedly larger. Moreover, kidney tissue sections of the KOT mice displayed a greater CaP and mixed microcrystal formation than the kidney sections of the WTT group, specifically in the outer and inner medullary and calyceal region; thus, a higher degree of calcifications and mixed calcium lithiasis in the kidneys of the KOT group was displayed. In our effort to find the Ca2+ signaling pathophysiology of PT cells, we found that PT cells from both treated groups (WTT and KOT) elicited a larger Ca2+ entry compared to the WT counterparts because of significant inhibition by the store-operated Ca2+ entry (SOCE) inhibitor, Pyr6. In the presence of both SOCE (Pyr6) and ROCE (receptor-operated Ca2+ entry) inhibitors (Pyr10), Ca2+ entry by WTT cells was moderately inhibited, suggesting that the Ca2+ and pH levels exerted sensitivity changes in response to ROCE and SOCE. An assessment of the gene expression profiles in the PT cells of WTT and KOT mice revealed a safeguarding effect of TRPC3 against detrimental processes (calcification, fibrosis, inflammation, and apoptosis) in the presence of higher pH and hypercalciuric conditions in mice. Together, these findings show that compromise in both the ROCE and SOCE mechanisms in the absence of TRPC3 under hypercalciuric plus higher tubular pH conditions results in higher CaP and mixed crystal formation and that TRPC3 is protective against those adverse effects.
Asunto(s)
Oxalato de Calcio , Hipercalciuria , Cálculos Renales , Ratones Noqueados , Animales , Hipercalciuria/metabolismo , Hipercalciuria/genética , Concentración de Iones de Hidrógeno , Ratones , Oxalato de Calcio/metabolismo , Cálculos Renales/metabolismo , Cálculos Renales/etiología , Cálculos Renales/patología , Fosfatos de Calcio/metabolismo , Nefrolitiasis/metabolismo , Nefrolitiasis/genética , Nefrolitiasis/patología , Calcio/metabolismo , Canales Catiónicos TRPC/metabolismo , Canales Catiónicos TRPC/genética , Túbulos Renales Proximales/metabolismo , Túbulos Renales Proximales/patología , Masculino , Modelos Animales de Enfermedad , Ratones Endogámicos C57BL , Acetazolamida/farmacologíaRESUMEN
OBJECTIVE: The purpose of this study is to develop an animal model of Chronic Intermittent Hypoxia (CIH) and investigate the role of the TRPC5 channel in cardiac damage in OSAHS rats. METHODS: Twelve male Sprague Dawley rats were randomly divided into the CIH group and the Normoxic Control (NC) group. Changes in structure, function, and pathology of heart tissue were observed through echocardiography, transmission electron microscopy, HE-staining, and TUNEL staining. RESULTS: The Interventricular Septum thickness at diastole (IVSd) and End-Diastolic Volume (EDV) of rats in the CIH group significantly increased, whereas the LV ejection fraction and LV fraction shortening significantly decreased. TEM showed that the myofilaments in the CIH group were loosely arranged, the sarcomere length varied, the cell matrix dissolved, the mitochondrial cristae were partly flocculent, the mitochondrial outer membrane dissolved and disappeared, and some mitochondria were swollen and vacuolated. The histopathological examination showed that the cardiomyocytes in the CIH group were swollen with granular degeneration, some of the myocardial fibers were broken and disorganized, and most of the nuclei were vacuolar and hypochromic. CONCLUSION: CIH promoted oxidative stress, the influx of Ca2+, and the activation of the CaN/NFATc signaling pathway, which led to pathological changes in the morphology and ultrastructure of cardiomyocytes, the increase of myocardial apoptosis, and the decrease of myocardial contractility. These changes may be associated with the upregulation of TRPC5.
Asunto(s)
Modelos Animales de Enfermedad , Hipoxia , Canales Catiónicos TRPC , Animales , Masculino , Ratas , Apoptosis/fisiología , Enfermedad Crónica , Ecocardiografía , Hipoxia/fisiopatología , Hipoxia/metabolismo , Etiquetado Corte-Fin in Situ , Microscopía Electrónica de Transmisión , Miocardio/metabolismo , Miocardio/patología , Miocardio/ultraestructura , Miocitos Cardíacos/ultraestructura , Miocitos Cardíacos/metabolismo , Miocitos Cardíacos/patología , Estrés Oxidativo/fisiología , Distribución Aleatoria , Ratas Sprague-Dawley , Canales Catiónicos TRPC/metabolismoRESUMEN
Parkinson's disease (PD) is a neurodegenerative disorder associated with mitochondrial dysfunctions and oxidative stress. However, to date, therapeutics targeting these pathological events have not managed to translate from bench to bedside for clinical use. One of the major reasons for the lack of translational success has been the use of classical model systems that do not replicate the disease pathology and progression with the same degree of robustness. Therefore, we employed a more physiologically relevant model involving alpha-synuclein-preformed fibrils (PFF) exposure to SH-SY5Y cells and Sprague Dawley rats. We further explored the possible involvement of transient receptor potential canonical 5 (TRPC5) channels in PD-like pathology induced by these alpha-synuclein-preformed fibrils with emphasis on amelioration of oxidative stress and mitochondrial health. We observed that alpha-synuclein PFF exposure produced neurobehavioural deficits that were positively ameliorated after treatment with the TRPC5 inhibitor clemizole. Furthermore, Clemizole also reduced p-alpha-synuclein and diminished oxidative stress levels which resulted in overall improvements in mitochondrial biogenesis and functions. Finally, the results of the pharmacological modulation were further validated using siRNA-mediated knockdown of TRPC5 channels, which also decreased p-alpha-synuclein expression. Together, the results of this study could be superimposed in the future for exploring the beneficial effects of TRPC5 channel modulation for other neurodegenerative disorders and synucleopathies.
Asunto(s)
Mitocondrias , Estrés Oxidativo , Ratas Sprague-Dawley , Canales Catiónicos TRPC , alfa-Sinucleína , alfa-Sinucleína/genética , alfa-Sinucleína/metabolismo , Animales , Ratas , Estrés Oxidativo/efectos de los fármacos , Humanos , Canales Catiónicos TRPC/genética , Canales Catiónicos TRPC/antagonistas & inhibidores , Mitocondrias/efectos de los fármacos , Mitocondrias/metabolismo , Línea Celular Tumoral , Masculino , Trastornos Parkinsonianos/tratamiento farmacológico , Trastornos Parkinsonianos/inducido químicamente , ARN Interferente Pequeño/genética , ARN Interferente Pequeño/farmacología , ARN Interferente Pequeño/uso terapéutico , Enfermedad de Parkinson Secundaria/inducido químicamente , Enfermedad de Parkinson Secundaria/tratamiento farmacológicoRESUMEN
Pulmonary hypertension (PH) is a devastating disease that lacks effective treatment options and is characterized by severe pulmonary vascular remodeling. Pulmonary arterial endothelial cell (PAEC) dysfunction drives the initiation and pathogenesis of pulmonary arterial hypertension. Canonical transient receptor potential (TRPC) channels, a family of Ca2+-permeable channels, play an important role in various diseases. However, the effect and mechanism of TRPCs on PH development have not been fully elucidated. Among the TRPC family members, TRPC4 expression was markedly upregulated in PAECs from hypoxia combined with SU5416 (HySu)-induced PH mice and monocrotaline (MCT)-treated PH rats, as well as in hypoxia-exposed PAECs, suggesting that TRPC4 in PAECs may participate in the occurrence and development of PH. In this study, we aimed to investigate whether TRPC4 in PAECs has an aggravating effect on PH and elucidate the molecular mechanisms. We observed that hypoxia treatment promoted PAEC apoptosis through a caspase-12/endoplasmic reticulum stress (ERS)-dependent pathway. Knockdown of TRPC4 attenuated hypoxia-induced apoptosis and caspase-3/caspase-12 activity in PAECs. Accordingly, adeno-associated virus (AAV) serotype 6-mediated pulmonary endothelial TRPC4 silencing (AAV6-Tie-shRNA-TRPC4) or TRPC4 antagonist suppressed PH progression as evidenced by reduced right ventricular systolic pressure (RVSP), pulmonary vascular remodeling, PAEC apoptosis and reactive oxygen species (ROS) production. Mechanistically, unbiased RNA sequencing (RNA-seq) suggested that TRPC4 deficiency suppressed the expression of the proapoptotic protein sushi domain containing 2 (Susd2) in hypoxia-exposed mouse PAECs. Moreover, TRPC4 activated hypoxia-induced PAEC apoptosis by promoting Susd2 expression. Therefore, inhibiting TRPC4 ameliorated PAEC apoptosis and hypoxic PH in animals by repressing Susd2 signaling, which may serve as a therapeutic target for the management of PH.
Asunto(s)
Apoptosis , Células Endoteliales , Hipertensión Pulmonar , Hipoxia , Canales Catiónicos TRPC , Animales , Ratones , Ratas , Células Cultivadas , Modelos Animales de Enfermedad , Estrés del Retículo Endoplásmico , Células Endoteliales/metabolismo , Células Endoteliales/patología , Hipertensión Pulmonar/metabolismo , Hipertensión Pulmonar/patología , Hipertensión Pulmonar/genética , Hipoxia/metabolismo , Indoles , Ratones Endogámicos C57BL , Monocrotalina/toxicidad , Arteria Pulmonar/patología , Arteria Pulmonar/metabolismo , Pirroles , Ratas Sprague-Dawley , Transducción de Señal , Canales Catiónicos TRPC/metabolismo , Canales Catiónicos TRPC/genética , Remodelación Vascular/genéticaRESUMEN
We performed a comprehensive study of the morphological, functional, and genetic features of moonwalker (MWK) mice, a mouse model of spinocerebellar ataxia caused by a gain of function of the TRPC3 channel. These mice show numerous behavioral symptoms including tremor, altered gait, circling behavior, impaired motor coordination, impaired motor learning and decreased limb strength. Cerebellar pathology is characterized by early and almost complete loss of unipolar brush cells as well as slowly progressive, moderate loss of Purkinje cell (PCs). Structural damage also includes loss of synaptic contacts from parallel fibers, swollen ER structures, and degenerating axons. Interestingly, no obvious correlation was observed between PC loss and severity of the symptoms, as the phenotype stabilizes around 2 months of age, while the cerebellar pathology is progressive. This is probably due to the fact that PC function is severely impaired much earlier than the appearance of PC loss. Indeed, PC firing is already impaired in 3 weeks old mice. An interesting feature of the MWK pathology that still remains to be explained consists in a strong lobule selectivity of the PC loss, which is puzzling considering that TRPC is expressed in every PC. Intriguingly, genetic analysis of MWK cerebella shows, among other alterations, changes in the expression of both apoptosis inducing and resistance factors possibly suggesting that damaged PCs initiate specific cellular pathways that protect them from overt cell loss.
Asunto(s)
Modelos Animales de Enfermedad , Fenotipo , Animales , Ratones , Cerebelo/patología , Cerebelo/metabolismo , Células de Purkinje/patología , Células de Purkinje/metabolismo , Canales Catiónicos TRPC/genética , Canales Catiónicos TRPC/metabolismo , Genotipo , Ataxias Espinocerebelosas/patología , Ataxias Espinocerebelosas/genética , Ataxias Espinocerebelosas/metabolismo , Ratones Mutantes Neurológicos , Ratones Endogámicos C57BL , Ratones TransgénicosRESUMEN
TRPC5 is a non-selective cation channel that is expressed in cardiomyocytes, but there is a lack of knowledge of its (patho)physiological role in vivo. Here, we examine the role of TRPC5 on cardiac function under basal conditions and during cardiac hypertrophy. Cardiovascular parameters were assessed in wild-type (WT) and global TRPC5 knockout (KO) mice. Despite no difference in blood pressure or activity, heart rate was significantly reduced in TRPC5 KO mice. Echocardiography imaging revealed an increase in stroke volume, but cardiac contractility was unaffected. The reduced heart rate persisted in isolated TRPC5 KO hearts, suggesting changes in basal cardiac pacing. Heart rate was further investigated by evaluating the reflex change following drug-induced pressure changes. The reflex bradycardic response following phenylephrine was greater in TRPC5 KO mice but the tachycardic response to SNP was unchanged, indicating an enhancement in the parasympathetic control of the heart rate. Moreover, the reduction in heart rate to carbachol was greater in isolated TRPC5 KO hearts. To evaluate the role of TRPC5 in cardiac pathology, mice were subjected to abdominal aortic banding (AAB). An exaggerated cardiac hypertrophy response to AAB was observed in TRPC5 KO mice, with an increased expression of hypertrophy markers, fibrosis, reactive oxygen species, and angiogenesis. This study provides novel evidence for a direct effect of TRPC5 on cardiac function. We propose that (1) TRPC5 is required for maintaining heart rate by regulating basal cardiac pacing and in response to pressure lowering, and (2) TRPC5 protects against pathological cardiac hypertrophy.