Virus-induced senescence (VIS) is a significant biological phenomenon, which is associated with declining immune function, accelerating aging process and causing aging-related diseases. A variety of common viruses, including RNA viruses (such as SARS-CoV-2), DNA viruses (such as herpesviruses and hepatitis B virus), and prions can cause VIS in host cells. The primary mechanisms include abnormal activation of the cGAS-STING signaling pathway, DNA damage response, and potential correlations with the integrated stress response due to intracellular phase separation. Viral infection and cellular senescence influence each other: cellular senescence serves as a defense to restrict viral replication and transmission, while some viruses exploit cellular senescence to enhance their infectivity and replication. Understanding the mechanisms of VIS is conducive to the development of therapeutic strategies for viral infections and promotion of healthy aging. However, there is lack of research on therapeutic targets and drug development in this field so far. Although senolytics may be effective for anti-senescent cells therapy, their efficacy for VIS needs evidence from further clinical trials. This article reviews the research progress on the connection between viral infection and cellular senescence, to provide insights for the prevention and treatment of aging related diseases.
Humans ; Cellular Senescence/physiology* ; Virus Diseases/physiopathology* ; Signal Transduction ; Nucleotidyltransferases/metabolism* ; DNA Damage ; Virus Replication ; COVID-19 ; Membrane Proteins/metabolism* ; SARS-CoV-2

BACKGROUND: Many factors are associated with the development and progression of liver fat and fibrosis; however, genetics and the gut microbiota are representative factors. Moreover, recent studies have indicated a link between host genes and the gut microbiota. This study investigated the effect of patatin-like phospholipase domain-containing 3 (PNPLA3) rs738409 (C > G), which has been reported to be most involved in the onset and progression of fatty liver, on liver fat and fibrosis in a cohort study related to gut microbiota in a non-fatty liver population. METHODS: This cohort study included 214 participants from the health check-up project in 2018 and 2022 who had non-fatty liver with controlled attenuation parameter (CAP) values <248 dB/m by FibroScan and were non-drinkers. Changes in CAP values and liver stiffness measurement (LSM), liver-related items, and gut microbiota from 2018 to 2022 were investigated separately for PNPLA3 rs738409 CC, CG, and GG genotypes. RESULTS: Baseline values showed no difference among the PNPLA3 rs738409 genotypes for any of the measurement items. From 2018 to 2022, the PNPLA3 rs738409 CG and GG genotype groups showed a significant increase in CAP and body mass index; no significant change was observed in the CC genotype group. LSM increased in all genotypes, but the rate of increase was highest in the GG genotype, followed by the CG and CC genotypes. Fasting blood glucose levels increased in all genotypes; however, HOMA-IR (Homeostasis Model Assessment of Insulin Resistance) increased significantly only in the GG genotype. HDL (high-density lipoprotein) and LDL (low-density lipoprotein) cholesterol levels significantly increased in all genotypes, whereas triglycerides did not show any significant changes in any genotype. As for the gut microbiota, the relative abundance of Feacalibacterium in the PNPLA3 rs738409 GG genotype decreased by 2% over 4 years, more than 2-fold compared to CC and GG genotypes. Blautia increased significantly in the CC group. CONCLUSION The results suggest that PNPLA3 G-allele carriers of non-fatty liver develop liver fat and fibrosis due to not only obesity and insulin resistance but also the deterioration of gut microbiota, which may require a relatively long course of time, even years.
Humans ; Gastrointestinal Microbiome ; Male ; Female ; Membrane Proteins/metabolism* ; Lipase/genetics* ; Middle Aged ; Liver Cirrhosis/epidemiology* ; Cohort Studies ; Genotype ; Adult ; Non-alcoholic Fatty Liver Disease/microbiology* ; Polymorphism, Single Nucleotide ; Acyltransferases ; Phospholipases A2, Calcium-Independent

OBJECTIVE: To elucidate the mechanism of Banxia Houpo Decoction (BHD) in treating gastroesophageal reflux disease (GERD) by integrating and utilizing the compound analysis, network pharmacology, and empirical verification. METHODS: Ultra-high performance liquid chromatography-high resolution mass spectrometry (UPLC-HRMS) was utilized to identify the primary compounds in BHD. Network pharmacology was employed to retrieve target genes. A GERD rat model was developed and 32 SD rats were randomly divided into model, BHD-L (3 g/kg), BHD-H (6 g/kg), and mosapride (0.75 mg/kg) groups using a random number table, 8 rats in each group. Eight rats without the construction of a GERD model were selected as the blank group. Esophageal damage was evaluated through visualization and histopathology evaluation. 5-hydroxytryptamine (5-HT) levels in serum and lower esophageal sphincter (LES) were determined by ELISA. LES contractility was measured with a force transducer, and serotonin transporter (SERT) and 5-HT4R expressions in LES were assessed by RT-PCR, Western blot, and immunofluorescence staining, respectively. RESULTS: UPLC-HRMS analysis identified 37 absorption peaks and 157 compounds in BHD. Functional enrichment identified SERT as a significant target for LES contractility. Histopathological findings indicated less severe esophageal mucosal damage in the BHD-H group compared with the model group. Although serum 5-HT levels showed no significant difference, 5-HT concentration in LES tissue was notably higher in the BHD-H group (P<0.05). Within the range from 10^-10 to 10^-7 mmol/L, LES contractility in the BHD-H and mosapride groups was significantly increased (P<0.05). Within the range from 3 × 10^-7 to 3 × 10^-6 mmol/L 5-HT, LES contractility in the BHD-H group was increased (P<0.05). No significant difference was detected within the range from 10^-5 to 10^-4 mmol/L 5-HT. Notably, SERT expression in the BHD-H group assessed by RT-PCR, Western blot, and immunofluorescence staining were significantly lower than that in the model group (all P<0.01); while 5-HT4R expression remained unchanged. CONCLUSION BHD may increase LES contractility by inhibiting SERT expression in LES tissue.
Animals ; Gastroesophageal Reflux/physiopathology* ; Drugs, Chinese Herbal/chemistry* ; Rats, Sprague-Dawley ; Network Pharmacology ; Male ; Serotonin/metabolism* ; Rats ; Disease Models, Animal ; Serotonin Plasma Membrane Transport Proteins/metabolism* ; Esophagus/drug effects*

OBJECTIVES: The neurotoxicity of carbon monoxide (CO) to the central nervous system is a key pathogenesis of delayed encephalopathy after acute carbon monoxide poisoning (DEACMP). Our previous study found that retinoic acid (RA) can suppress the neurotoxic effects of CO. This study further explores, in vivo and in vitro, the molecular mechanisms by which RA alleviates CO-induced central nervous system damage. METHODS: A cytotoxic model was established using the mouse hippocampal neuronal cell line HT22 and primary oligodendrocytes exposed to CO, and a DEACMP animal model was established in adult Kunming mice. Cell viability and apoptosis of hippocampal neurons and oligodendrocytes were assessed using the 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay and Annexin V/propidium iodide (PI) double staining. The transcriptional and protein expression of each gene was detected using real-time fluorescence quantitative PCR (RT-qPCR) and Western blotting. Long noncoding RNA (lncRNA) SNHG15 and LINGO-1 were knocked down or overexpressed to observe changes in neurons and oligodendrocytes. In DEACMP mice, SNHG15 or LINGO-1 were knocked down to assess changes in central nervous tissue and downstream protein expression. RESULTS: RA at 10 and 20 μmol/L significantly reversed CO-induced apoptosis of hippocampal neurons and oligodendrocytes, downregulation of SNHG15 and LINGO-1, and upregulation of brain-derived neurotrophic factor (BDNF) and tyrosine kinase receptor B (TrkB) (all P<0.05). Overexpression of SNHG15 or LINGO-1 weakened the protective effect of RA against CO-induced cytotoxicity (all P<0.05). Knockdown of SNHG15 or LINGO-1 alleviated CO-induced apoptosis of hippocampal neurons and oligodendrocytes and upregulated BDNF and TrkB expression levels (all P<0.05). Experiments in DEACMP model mice showed that knockdown of SNHG15 or LINGO-1 mitigated central nervous system injury in DEACMP (all P<0.05). CONCLUSIONS RA alleviates CO-induced apoptosis of hippocampal neurons and oligodendrocytes, thereby reducing central nervous system injury and exerting neuroprotective effects. LncRNA SNHG15 and LINGO-1 are key molecules mediating RA-induced inhibition of neuronal apoptosis and are associated with the BDNF/TrkB pathway. These findings provide a theoretical framework for optimizing the clinical treatment of DEACMP and lay an experimental foundation for elucidating its molecular mechanisms.
Animals ; RNA, Long Noncoding/physiology* ; Brain-Derived Neurotrophic Factor/genetics* ; Carbon Monoxide Poisoning/complications* ; Mice ; Tretinoin/pharmacology* ; Nerve Tissue Proteins/metabolism* ; Membrane Proteins/metabolism* ; Apoptosis/drug effects* ; Hippocampus/cytology* ; Receptor, trkB/metabolism* ; Neurons/drug effects* ; Male ; Brain Diseases/etiology* ; Oligodendroglia/drug effects* ; Signal Transduction ; Cell Line

OBJECTIVE: To investigate the role of telomerase reverse transcriptase (TERT) in alleviating doxorubicin (DOX)-induced cardiotoxicity. METHODS: (1) Cell experiments: rat H9c2 cardiomyocytes were divided into control group (CON group), null adenovirus transfection group (NC group), TERT overexpression adenovirus transfection group (TERT group), DOX group (treated with 1 μmol/L DOX for 12 hours), DOX+NC group, and DOX+TERT group (null adenovirus or TERT overexpression adenovirus were transfected for 24 hours and then treated with 1 μmol/L DOX for 12 hours). The mRNA expression of TERT in cardiomyocytes was detected by real-time fluorescence quantitative polymerase chain reaction (RT-qPCR). The level of mitochondrial membrane potential was detected by immunofluorescence. The expression levels of intracellular Bax, Bcl-2, microtubule-associated protein 1 light chain 3 (LC3) and p62 were detected by Western blotting. (2) Animal experiments: male C57BL/6 mice were randomly divided into a sham operation group (Sham group), DOX group (acute cardiotoxicity model was constructed by intraperitoneal injection of DOX 15 mg/kg), DOX+NC group and DOX+TERT group (modeled after transfection with airborne adenovirus or TERT overexpression adenovirus for 7 days). After 7 days of modeling, the area of myocardial fibrosis was detected by Sirius scarlet staining, and cardiac function was detected by echocardiography. RESULTS: (1) Cellular experiments: the mRNA expression level of TERT was significantly higher in the TERT group compared with the CON and NC groups. Compared with the CON group, the TERT mRNA expression level of cardiomyocytes in the DOX group and the DOX+NC group were significantly lower, the level of mitochondrial membrane potential was significantly lower, the protein expressions of Bax and LC3 were significantly increased, and the protein expressions of Bcl-2 and p62 were significantly decreased. No significant differences were found between the DOX group and DOX+NC group. Compared with the DOX group and DOX+NC group, the TERT mRNA expression level was increased in the DOX+TERT group (relative expression: 1.02±0.10 vs. 0.61±0.05, 0.54±0.03, both P < 0.05), the level of mitochondrial membrane potential was significantly increased (1.14±0.05 vs. 0.96±0.01, 0.96±0.01, both P < 0.05), the protein expressions of Bax and LC3 were significantly decreased, and the protein expressions of Bcl-2 and p62 were significantly increased (Bax/β-actin: 0.88±0.01 vs. 1.31±0.02, 1.26±0.01; LC3-II/I: 2.16±0.05 vs. 2.64±0.06, 2.58±0.02; Bcl-2/β-actin: 0.65±0.01 vs. 0.40±0.01, 0.41±0.01; p62/β-actin: 0.45±0.01 vs. 0.23±0.02, 0.29±0.01; all P < 0.05). (2) Animal experiments: compared with the Sham group, the percentage of myocardial fibrosis area was significantly increased and left ventricular ejection fraction (LVEF) and fractional shortening (FS) were significantly decreased in the DOX group and DOX+NC group. Compared with the DOX group and DOX+NC group, the percentage of myocardial fibrotic area was significantly decreased in the DOX+TERT group (%: 2.33±0.06 vs. 3.76±0.07, 3.87±0.06, both P < 0.05), and the LVEF and FS were significantly increased [LVEF (%): 67.00±1.14 vs. 54.60±1.57, 53.40±2.18; FS (%): 38.60±0.51 vs. 30.60±1.10, 30.00±0.71; all P < 0.05]. CONCLUSION Up-regulation of TERT expression can inhibit DOX-induced cardiomyocyte autophagy and apoptosis, attenuate DOX-induced myocardial fibrosis in mice, improve cardiac function, and thus alleviate DOX-induced cardiotoxicity.
Animals ; Doxorubicin/toxicity* ; Telomerase/metabolism* ; Myocytes, Cardiac/metabolism* ; Rats ; Male ; Cardiotoxicity ; Mice, Inbred C57BL ; Mice ; Membrane Potential, Mitochondrial ; Adenoviridae ; bcl-2-Associated X Protein/metabolism* ; Proto-Oncogene Proteins c-bcl-2/metabolism* ; Transfection ; Apoptosis

OBJECTIVE: To investigate the role and mechanism of the cyclic guanosine monophosphate-adenosine monophosphate synthase/stimulator of interferon gene (cGAS/STING) pathway in oleic acid-induced acute lung injury (ALI) in mice. METHODS: Male wild-type C57BL/6J mice were randomly divided into five groups (each n = 10): normal control group, ALI model group, and 5, 50, 500 μg/kg inhibitor pretreatment groups. The ALI model was established by tail vein injection of oleic acid (7 mL/kg), while the normal control group received no intervention. The inhibitor pretreatment groups were intraperitoneally injected with the corresponding doses of cGAS inhibitor RU.521 respectively 1 hour before modeling. At 24 hours post-modeling, blood was collected, and mice were sacrificed. Lung tissue pathological changes were observed under light microscopy after hematoxylin-eosin (HE) staining, and pathological scores were assessed. Western blotting was used to detect the protein expressions of cGAS, STING, phosphorylated TANK-binding kinase 1 (p-TBK1), phosphorylated interferon regulatory factor 3 (p-IRF3), and phosphorylated nuclear factor-κB p65 (p-NF-κB p65) in lung tissue. Immunohistochemistry was performed to observe STING and p-NF-κB positive expressions in lung tissue. Serum interferon-β (IFN-β) levels were measured by enzyme-linked immunosorbent assay (ELISA). RESULTS: Compared with the normal control group, the ALI model group exhibited significant focal alveolar thickening, intra-alveolar hemorrhage, pulmonary capillary congestion, and neutrophil infiltration in the pulmonary interstitium and alveoli, along with markedly increased pathological scores (10.33±0.58 vs. 1.33±0.58, P < 0.05). Protein expressions of cGAS, STING, p-TBK1, p-IRF3, and p-NF-κB p65 in lung tissue significantly increased [cGAS protein (cGAS/β-actin): 1.24±0.02 vs. 0.56±0.02, STING protein (STING/β-actin): 1.27±0.01 vs. 0.55±0.01, p-TBK1 protin (p-TBK1/β-actin): 1.34±0.03 vs. 0.22±0.01, p-IRF3 protein (p-IRF3/β-actin): 1.23±0.02 vs. 0.36±0.01, p-NF-κB p65 protein (p-NF-κB p65/β-actin): 1.30±0.02 vs. 0.53±0.02, all P < 0.05], positive expressions of STING and p-NF-κB in lung tissue were significantly elevated [STING (A value): 0.51±0.03 vs. 0.30±0.07, p-NF-κB (A value): 0.57±0.05 vs. 0.31±0.03, both P < 0.05], and serum IFN-β levels were also significantly higher (ng/L: 256.02±3.84 vs. 64.15±1.17, P < 0.05). The cGAS inhibitor pretreatment groups showed restored alveolar structural integrity, reduced inflammatory cell infiltration, and decreased hemorrhage area, along with dose-dependent lower pathological scores as well as the protein expressions of cGAS, STING, p-TBK1, p-IRF3 and p-NF-κB p65 in lung tissue, with significant differences between the 500 μg/kg inhibitor group and ALI model group [pathological score: 2.67±0.58 vs. 10.33±0.58, cGAS protein (cGAS/β-actin): 0.56±0.03 vs. 1.24±0.02, STING protein (STING/β-actin): 0.67±0.03 vs. 1.27±0.01, p-TBK1 protein (p-TBK1/β-actin): 0.28±0.01 vs. 1.34±0.03, p-IRF3 protein (p-IRF3/β-actin): 0.32±0.01 vs. 1.23±0.02, p-NF-κB p65 protein (p-NF-κB p65/β-actin): 0.63±0.01 vs. 1.30±0.02, all P < 0.05]. Compared with the ALI model group, positive expressions of STING and p-NF-κB in lung tissue were significantly reduced in the 500 μg/kg inhibitor group [STING (A value): 0.40±0.01 vs. 0.51±0.03, p-NF-κB (A value): 0.43±0.02 vs. 0.57±0.05, both P < 0.05], and serum IFN-β levels were also markedly reduced (ng/L: 150.03±6.19 vs. 256.02±3.84, P < 0.05). CONCLUSIONS The cGAS/STING pathway is activated in oleic acid-induced ALI, leading to exacerbated inflammatory responses and increased lung damage. RU.521 can inhibit cGAS, thereby down-regulating the expression of pathway proteins and cytokines, and providing protection to lung tissue.
Animals ; Acute Lung Injury/chemically induced* ; Male ; Nucleotidyltransferases/metabolism* ; Mice ; Signal Transduction ; Mice, Inbred C57BL ; Membrane Proteins/metabolism* ; Oleic Acid/adverse effects* ; Transcription Factor RelA/metabolism* ; Lung/pathology* ; Interferon Regulatory Factor-3/metabolism* ; Disease Models, Animal

Dysfunction of drug transporters significantly affects therapeutic outcomes and drug efficacy in patients with liver injury. Clinical and experimental evidence demonstrates that liver injury involves complex inter-organ interactions among the brain, eye, liver, intestine, and kidney. Recent advances in basic and clinical research have illuminated the physiologic and molecular mechanisms underlying transporter alterations in liver injury, particularly those associated with bilirubin, reactive oxygen species, ammonia, bile acid, and inflammatory factors. Notably, the influence of these transporter modifications on drug pharmacokinetics in liver injury patients remains inadequately understood. Additional research is necessary to fully comprehend these effects and their therapeutic implications. The documented alterations of transporters in distant organs across various liver diseases indicate that dosage modifications may be required when administering transporter-substrate drugs, including both traditional Chinese and Western medicines, to patients with liver dysfunction. This strategy helps maintain drug concentrations within therapeutic ranges while reducing adverse reactions. Furthermore, when utilizing transporter inducers or inhibitors clinically, consideration of their long-term effects on transporters and subsequent therapeutic impact is essential. Careful attention must be paid to avoid compromising the elimination of toxic metabolites and proteins when inhibiting these transporters. Similarly, prudent use of inducers or inducer-type therapeutic drugs is necessary to prevent enhanced drug resistance. This review examines recent clinical and experimental findings regarding the inter-organ interaction of drug transporters in liver injury conditions and their clinical relevance.
Humans ; Liver/drug effects* ; Animals ; Chemical and Drug Induced Liver Injury/metabolism* ; Membrane Transport Proteins/metabolism* ; Biological Transport ; Liver Diseases/drug therapy* ; Pharmaceutical Preparations/metabolism*

OBJECTIVE: To reveal the effects and potential mechanisms by which synaptic vesicle glycoprotein 2A (SV2A) influences the distribution of amyloid precursor protein (APP) in the trans-Golgi network (TGN), endolysosomal system, and cell membranes and to reveal the effects of SV2A on APP amyloid degradation. METHODS: Colocalization analysis of APP with specific tagged proteins in the TGN, ensolysosomal system, and cell membrane was performed to explore the effects of SV2A on the intracellular transport of APP. APP, β-site amyloid precursor protein cleaving enzyme 1 (BACE1) expressions, and APP cleavage products levels were investigated to observe the effects of SV2A on APP amyloidogenic processing. RESULTS: APP localization was reduced in the TGN, early endosomes, late endosomes, and lysosomes, whereas it was increased in the recycling endosomes and cell membrane of SV2A-overexpressed neurons. Moreover, Arl5b (ADP-ribosylation factor 5b), a protein responsible for transporting APP from the TGN to early endosomes, was upregulated by SV2A. SV2A overexpression also decreased APP transport from the cell membrane to early endosomes by downregulating APP endocytosis. In addition, products of APP amyloid degradation, including sAPPβ, Aβ _1-42, and Aβ _1-40, were decreased in SV2A-overexpressed cells. CONCLUSION These results demonstrated that SV2A promotes APP transport from the TGN to early endosomes by upregulating Arl5b and promoting APP transport from early endosomes to recycling endosomes-cell membrane pathway, which slows APP amyloid degradation.
Amyloid beta-Protein Precursor/genetics* ; Membrane Glycoproteins/genetics* ; Animals ; Protein Transport ; Nerve Tissue Proteins/genetics* ; Humans ; Mice ; Endosomes/metabolism* ; trans-Golgi Network/metabolism*

OBJECTIVE: To observe the effects of moxibustion at "Feishu" (BL13) and "Xinshu" (BL15) on the circular RNA of exon 2-5 of the Pan3 gene (circPAN3), forkhead box O3 (FOXO3), and Bcl-2/adenovirus E1B19kDa-interacting protein 3 (BNIP3) in rats with chronic heart failure (CHF), and explore the potential mechanisms of moxibustion in alleviating myocardial fibrosis. METHODS: Ten rats of 60 male SPF-grade SD rats were randomly assigned into a normal group. The remaining rats underwent left anterior descending coronary artery (LAD) ligation to establish the CHF model. Forty successfully modeled rats were randomly divided into a model group, a moxibustion group, a rapamycin (RAPA) group, and a moxibustion+RAPA group, with 10 rats in each group. The moxibustion group received mild moxibustion at bilateral "Feishu" (BL13) and "Xinshu" (BL15), 30 min per session. The RAPA group received intraperitoneal injection of the autophagy activator RAPA (1 mg/kg). The moxibustion+RAPA group first received RAPA injection, followed by mild moxibustion at bilateral "Feishu" (BL13) and "Xinshu" (BL15). All interventions were administered once daily for 4 consecutive weeks. After the intervention, cardiac ultrasound was used to measure ejection fraction (EF) and left ventricular fractional shortening (FS). Serum placental growth factor (PLGF) level was determined by ELISA. Myocardial tissue morphology and collagen volume were assessed using hematoxylin-eosin (HE) staining and Masson's trichrome staining. The expression levels of circPAN3, FOXO3, and BNIP3 mRNA in myocardial tissue were detected by real-time PCR, while FOXO3 and BNIP3 protein expression levels were analyzed by Western blot. RESULTS: Compared with the normal group, the model group exhibited myocardial cell disorder, severe fibrosis, and increased collagen volume (P<0.01), along with significantly decreased EF, FS, and circPAN3 mRNA expression in myocardial tissue (P<0.01), and the serum PLGF level, as well as FOXO3 and BNIP3 mRNA and protein expression in myocardial tissue were increased (P<0.01). Compared with the model group, the moxibustion group showed reduced myocardial fibrosis, decreased collagen volume (P<0.01), increased EF, FS, and circPAN3 mRNA expression in myocardial tissue (P<0.01), and decreased serum PLGF level as well as FOXO3 and BNIP3 mRNA and protein expression in myocardial tissue (P<0.01). Compared with the model group, the RAPA group showed further deterioration in these parameters (P<0.01). Compared with the RAPA group, the moxibustion+RAPA group exhibited alleviation of myocardial fibrosis, reduced collagen volume (P<0.01), increased EF, FS, and circPAN3 mRNA expression in myocardial tissue (P<0.01), and decreased serum PLGF level as well as FOXO3 and BNIP3 mRNA and protein expression in myocardial tissue (P<0.01). CONCLUSION Moxibustion could alleviate myocardial fibrosis in CHF rats, possibly through upregulation of myocardial circPAN3 expression, downregulation of FOXO3 and BNIP3 expression, and inhibition of excessive myocardial autophagy.
Animals ; Moxibustion ; Heart Failure/metabolism* ; Male ; Rats ; Rats, Sprague-Dawley ; Myocardium/pathology* ; RNA, Circular/metabolism* ; Membrane Proteins/metabolism* ; Forkhead Box Protein O3/metabolism* ; Acupuncture Points ; Humans ; Fibrosis/genetics* ; Chronic Disease/therapy* ; Mitochondrial Proteins

OBJECTIVE: To observe the effect of electroacupuncture (EA) at "Hegu" (LI4) and "Taichong" (LR3) on DNA methylation of the solute carrier family 6 member 4 (SLC6A4) gene promoter region in the hippocampus of depressed rats, and to explore the potential antidepressant mechanism of EA. METHODS: Thirty male Sprague-Dawley rats were randomly divided into a blank group, a model group, a medication group, a 5-Azacytidine (5-AZA) group, and an EA group, 6 rats in each group. Depression models were established in the model group, the medication group, the 5-AZA group, and the EA group using chronic unpredictable mild stress (CUMS) combined with solitary housing. The medication group was treated with intragastric administration of fluoxetine hydrochloride capsules; the 5-AZA group was treated with intraperitoneal injection of 5-AZA; the EA group was treated with EA at bilateral "Hegu" (LI4) and "Taichong" (LR3), with disperse-dense wave, frequency of 2 Hz/100 Hz, and intensity of 1-1.2 mA, 20 min each session. All the treatment was given in three groups once daily for 21 consecutive days. Behavioral changes were evaluated by sucrose preference test, open field test, and novelty-suppressed feeding test. Serum levels of serotonin (5-HT), dopamine (DA), and norepinephrine (NE) were measured by ELISA. The expression of SLC6A4 and 5-HT1AR protein and mRNA in hippocampus was detected by Western blot and real-time quantitative PCR, respectively. DNA methylation status of the SLC6A4 promoter region in hippocampal tissue was analyzed by bisulfite sequencing PCR (BSP). RESULTS: Compared with the blank group, the model group showed decreased sucrose preference, reduced total locomotor distance, and prolonged latency to feeding (P<0.05), decreased serum 5-HT, DA, and NE levels (P<0.05), downregulated hippocampal SLC6A4 and 5-HT1AR protein and mRNA expression (P<0.05), and increased CpG site methylation rate of the SLC6A4 promoter region (P<0.05). Compared with the model group, the medication group, the 5-AZA group, and the EA group exhibited increased sucrose preference, increased total locomotor distance, shortened latency to feeding (P<0.05), elevated serum 5-HT, DA, and NE levels (P<0.05), upregulated hippocampal SLC6A4 and 5-HT1AR protein and mRNA expression (P<0.05), and reduced CpG site methylation rate of the SLC6A4 promoter (P<0.05). Compared with the medication group and the 5-AZA group, the EA group showed higher sucrose preference, greater total locomotor distance, shorter latency to feeding (P<0.05), and increased serum DA and NE levels (P<0.05). CONCLUSION EA could improve depressive behaviors in depressed rat models. The underlying mechanism may involve inhibition of SLC6A4 hypermethylation in the hippocampus on the serotonergic system, upregulation of SLC6A4 and 5-HT1AR protein and mRNA expression, and elevation of monoamine neurotransmitters such as 5-HT.
Animals ; Electroacupuncture ; Male ; Hippocampus/metabolism* ; Rats, Sprague-Dawley ; Rats ; Acupuncture Points ; DNA Methylation ; Depression/metabolism* ; Promoter Regions, Genetic ; Serotonin Plasma Membrane Transport Proteins/metabolism* ; Humans