BACKGROUND:Currently,there are many modeling methods for pelvic organ prolapse animal models,and the commonly used methods are vaginal balloon dilatation,oophorectomy and the combination of the two.There is no study comparing the three modeling methods in detail.OBJECTIVE:To construct and validate a rat animal model of pelvic organ prolapse using three different methods and to identify the advantages and disadvantages of various models.METHODS:Seventy-two 8-week SPF-grade female Sprague-Dawley rats were selected and randomly divided into four groups,namely,vaginal balloon dilatation group,ovariectomy group,ovariectomy combined with vaginal balloon dilatation group(the combined group),and the sham-operated group(no ovariectomy and no vaginal dilatation).The vaginal wall tissues of rats were collected at 4,8 and 12 weeks after the operation for hematoxylin-eosin staining,Masson staining,EVG staining and immunohistochemical staining of α-smooth muscle actin,Vimentin and matrix metalloproteinase 9 detection,and the pelvic floor muscle tissues were taken at 4,8 and 12 weeks after the operation for hematoxylin-eosin staining,Masson staining and EVG staining.RESULTS AND CONCLUSION:(1)Hematoxylin-eosi staining showed that there was no significant difference in the decrease of vaginal epithelial layer thickness in the vaginal balloon dilatation group compared with the sham-operated group,(P＞0.05),while the thickness of the vaginal epithelial layer was significantly reduced in the ovariectomy group and the ovariectomy combined with vaginal balloon dilation group(P＜0.001),and the reduction was more significant in the ovariectomy combined with vaginal balloon dilation group,remained stable at 8 weeks after surgery and lasted until 12 weeks.(2)The changes in the content of collagen fibers and elastic fibers in the vaginal wall stained by Masson and EVG staining were the same as the changes in the thickness of the vaginal epithelial layer stained by hematoxylin-eosin,and there were no changes in collagen fibers and elastic fibers in the pelvic floor muscle tissues of the treatment groups.(3)At 4,8 and 12 weeks after treatment,there was no significant difference in the expression levels of α-smooth muscle actin,Vimentin and matrix metalloproteinase 9 in the vaginal wall tissue of the balloon dilation group compared with the control group(P＞0.05),whereas the expression levels of α-smooth muscle actin and Vimentin were significantly decreased in the ovariectomy group and ovariectomy combined with vaginal balloon dilation group(P＜0.01)and the expression of matrix metalloproteinase 9 showed a significant increase(P＜0.01),with a more pronounced increase in the ovariectomy combined with vaginal balloon dilation group,and the increase reached a stable state at 8 weeks after surgery and could persist up to 12 weeks.To conclude,vaginal balloon dilatation could not maintain the degeneration of pelvic organ prolapse formed by the vaginal wall for a long period,and both ovariectomy and the combined method can be used.Ovariectomy combined with vaginal balloon dilatation can significantly accelerate and aggravate the formation of typical histological features of pelvic organ prolapse in vaginal wall tissues,effectively shorten the experimental period,and improve the efficiency.These effects reach a stable state at 8 weeks after surgery and can be sustained up to 12 weeks,which is practical and convenient for the study of pelvic organ prolapse animal models.

BACKGROUND:Currently,there are many modeling methods for pelvic organ prolapse animal models,and the commonly used methods are vaginal balloon dilatation,oophorectomy and the combination of the two.There is no study comparing the three modeling methods in detail.OBJECTIVE:To construct and validate a rat animal model of pelvic organ prolapse using three different methods and to identify the advantages and disadvantages of various models.METHODS:Seventy-two 8-week SPF-grade female Sprague-Dawley rats were selected and randomly divided into four groups,namely,vaginal balloon dilatation group,ovariectomy group,ovariectomy combined with vaginal balloon dilatation group(the combined group),and the sham-operated group(no ovariectomy and no vaginal dilatation).The vaginal wall tissues of rats were collected at 4,8 and 12 weeks after the operation for hematoxylin-eosin staining,Masson staining,EVG staining and immunohistochemical staining of α-smooth muscle actin,Vimentin and matrix metalloproteinase 9 detection,and the pelvic floor muscle tissues were taken at 4,8 and 12 weeks after the operation for hematoxylin-eosin staining,Masson staining and EVG staining.RESULTS AND CONCLUSION:(1)Hematoxylin-eosi staining showed that there was no significant difference in the decrease of vaginal epithelial layer thickness in the vaginal balloon dilatation group compared with the sham-operated group,(P＞0.05),while the thickness of the vaginal epithelial layer was significantly reduced in the ovariectomy group and the ovariectomy combined with vaginal balloon dilation group(P＜0.001),and the reduction was more significant in the ovariectomy combined with vaginal balloon dilation group,remained stable at 8 weeks after surgery and lasted until 12 weeks.(2)The changes in the content of collagen fibers and elastic fibers in the vaginal wall stained by Masson and EVG staining were the same as the changes in the thickness of the vaginal epithelial layer stained by hematoxylin-eosin,and there were no changes in collagen fibers and elastic fibers in the pelvic floor muscle tissues of the treatment groups.(3)At 4,8 and 12 weeks after treatment,there was no significant difference in the expression levels of α-smooth muscle actin,Vimentin and matrix metalloproteinase 9 in the vaginal wall tissue of the balloon dilation group compared with the control group(P＞0.05),whereas the expression levels of α-smooth muscle actin and Vimentin were significantly decreased in the ovariectomy group and ovariectomy combined with vaginal balloon dilation group(P＜0.01)and the expression of matrix metalloproteinase 9 showed a significant increase(P＜0.01),with a more pronounced increase in the ovariectomy combined with vaginal balloon dilation group,and the increase reached a stable state at 8 weeks after surgery and could persist up to 12 weeks.To conclude,vaginal balloon dilatation could not maintain the degeneration of pelvic organ prolapse formed by the vaginal wall for a long period,and both ovariectomy and the combined method can be used.Ovariectomy combined with vaginal balloon dilatation can significantly accelerate and aggravate the formation of typical histological features of pelvic organ prolapse in vaginal wall tissues,effectively shorten the experimental period,and improve the efficiency.These effects reach a stable state at 8 weeks after surgery and can be sustained up to 12 weeks,which is practical and convenient for the study of pelvic organ prolapse animal models.

ObjectiveSpinal cord injury (SCI) directly impairs the regulatory function of the autonomic nervous system, induces intestinal dysfunction, and significantly reduces patients’ quality of life. Preclinical studies have shown that electroacupuncture (EA) therapy can regulate the brain-gut axis and is used to treat central nervous system diseases such as major depressive disorder, Alzheimer’s disease and Parkinson’s disease. Recent research has established that fecal microbiota transplantation (FMT) from EA-treated SCI rats restored intestinal motility and colonic morphology. However, it remains unclear whether the regulation of gut microbiota by EA therapy directly contributes to neural repair after SCI. This study aims to explore whether gut microbiota mediates the neuroprotective effect of EA in the treatment of SCI and its possible mechanism. MethodsThe study employed RNA transcriptome analysis of spinal cord tissue to characterize gene expression profiles and to identify key signaling pathways following EA treatment for SCI. Hematoxylin-Eosin (HE) staining and Nissl staining were used to observe the morphological changes in spinal cord tissue. Western blot (WB) and enzyme-linked immunosorbent assay (ELISA) were applied to detect the effects of EA on the expression of proteins related to nucleotide-binding domain leucine-rich repeat and pyrin domain-containing receptor 3 (NLRP3) -dependent pyroptosis. Using 16S rDNA sequencing, the study observed alterations in gut microbiota diversity and community composition in SCI rats. Prior to establishing SCI models, rats were pretreated with an antibiotic cocktail to induce gut dysbiosis, and the effects on intestinal function and spinal cord neural repair were evaluated. FMT was performed to investigate the regulatory effects of post-EA FMT on motor function, general status, liver and spleen indices, and NLRP3-mediated pyroptosis in SCI rats. ResultsEA improved motor function and reduced regulated neuronal cell death in SCI rats. Transcriptomic analysis demonstrated the activation of immune- and inflammation-related pathways post-SCI, including NOD-like receptors, nuclear factor-kappa B(NF-κB), and Toll-like receptor (TLR) pathways. EA primarily influenced intestinal inflammation and autoimmune functions. 16S rDNA sequencing illustrated that EA did not alter the diversity of gut microbiota. However, EA altered the gut microbiota composition in SCI rats, increasing Lactobacillus and Akkermansia genera while rebalancing the Firmicutes/Bacteroidetes ratio. Furthermore, depletion of gut microbiota by antibiotics disrupted the intestinal barrier, reduced the expression of intestinal barrier proteins Zonula Occludens-1 (ZO-1) and Occludin, elevated serum lipopolysaccharide-binding protein (LBP) levels, exacerbated spinal cord tissue damage, and hindered motor function recovery in SCI rats. FMT from donors treated with EA reduced LBP levels in the intestine, blood, and spinal cord of rats, inhibited the TLR4 myeloid differentiation primary response protein 88 (MyD88)-NF‑κB pathway and NLRP3-dependent pyroptosis, and improved motor function. On the other hand, FMT treatment resulted in decreased body weight and food intake, whereas FMT using EA-treated donors effectively alleviated these alterations. ConclusionEA effectively alleviated neuroinflammatory responses in rats with SCI, primarily through regulating the gut microbiota and suppressing the NLRP3-dependent pyroptosis signaling pathway.

ObjectiveSpinal cord injury (SCI) directly impairs the regulatory function of the autonomic nervous system, induces intestinal dysfunction, and significantly reduces patients’ quality of life. Preclinical studies have shown that electroacupuncture (EA) therapy can regulate the brain-gut axis and is used to treat central nervous system diseases such as major depressive disorder, Alzheimer’s disease and Parkinson’s disease. Recent research has established that fecal microbiota transplantation (FMT) from EA-treated SCI rats restored intestinal motility and colonic morphology. However, it remains unclear whether the regulation of gut microbiota by EA therapy directly contributes to neural repair after SCI. This study aims to explore whether gut microbiota mediates the neuroprotective effect of EA in the treatment of SCI and its possible mechanism. MethodsThe study employed RNA transcriptome analysis of spinal cord tissue to characterize gene expression profiles and to identify key signaling pathways following EA treatment for SCI. Hematoxylin-Eosin (HE) staining and Nissl staining were used to observe the morphological changes in spinal cord tissue. Western blot (WB) and enzyme-linked immunosorbent assay (ELISA) were applied to detect the effects of EA on the expression of proteins related to nucleotide-binding domain leucine-rich repeat and pyrin domain-containing receptor 3 (NLRP3) -dependent pyroptosis. Using 16S rDNA sequencing, the study observed alterations in gut microbiota diversity and community composition in SCI rats. Prior to establishing SCI models, rats were pretreated with an antibiotic cocktail to induce gut dysbiosis, and the effects on intestinal function and spinal cord neural repair were evaluated. FMT was performed to investigate the regulatory effects of post-EA FMT on motor function, general status, liver and spleen indices, and NLRP3-mediated pyroptosis in SCI rats. ResultsEA improved motor function and reduced regulated neuronal cell death in SCI rats. Transcriptomic analysis demonstrated the activation of immune- and inflammation-related pathways post-SCI, including NOD-like receptors, nuclear factor-kappa B(NF-κB), and Toll-like receptor (TLR) pathways. EA primarily influenced intestinal inflammation and autoimmune functions. 16S rDNA sequencing illustrated that EA did not alter the diversity of gut microbiota. However, EA altered the gut microbiota composition in SCI rats, increasing Lactobacillus and Akkermansia genera while rebalancing the Firmicutes/Bacteroidetes ratio. Furthermore, depletion of gut microbiota by antibiotics disrupted the intestinal barrier, reduced the expression of intestinal barrier proteins Zonula Occludens-1 (ZO-1) and Occludin, elevated serum lipopolysaccharide-binding protein (LBP) levels, exacerbated spinal cord tissue damage, and hindered motor function recovery in SCI rats. FMT from donors treated with EA reduced LBP levels in the intestine, blood, and spinal cord of rats, inhibited the TLR4 myeloid differentiation primary response protein 88 (MyD88)-NF‑κB pathway and NLRP3-dependent pyroptosis, and improved motor function. On the other hand, FMT treatment resulted in decreased body weight and food intake, whereas FMT using EA-treated donors effectively alleviated these alterations. ConclusionEA effectively alleviated neuroinflammatory responses in rats with SCI, primarily through regulating the gut microbiota and suppressing the NLRP3-dependent pyroptosis signaling pathway.

ObjectiveTo investigate and analyze an outbreak of rotavirus infectious diarrhea in a prison in Chongqing Municipality, to provide a basis for adult rotavirus surveillance and prevention, and to explore the public health problems in special settings. MethodsA retrospective survey was conducted to collect and analyze data on individual cases with diarrheal disease on-site. The clinical characteristics, as well as the temporal, spatial and geographical distribution patterns of the epidemic were described. Multi-pathogen detection tests were conducted both on diarrhea cases and environmental samples, with viral genotyping performed on positive samples. A case-control analysis was performed to identify the causes of the outbreak, and an SEIR model was adopted to predict the outbreak trend and evaluate the effectiveness of interventions. ResultsA total of 65 cases were found among the inmates, with an attack rate of 2.03%. The predominant clinical manifestations included diarrhea (89.23%), watery stool (73.85%), and dehydration (18.46%). The epidemic curve indicated a “human-to-human” transmission pattern, with an average incubation period of 5‒6 days. The attack rates among chefs in the main canteen (80.00%, 8/10) and caterers (28.33%, 17/60) were significantly higher than those of other inmates （P<0.05）. Multi-pathogen polymerase chain reaction (PCR) testing detected positive for group A rotavirus, with the viral genotyping identified as G9P [8] strain. Factors such as unprotected "bare-handed" food distribution among cases with diarrhea (OR=9.512, 95%CI: 4.261‒21.234) and close contact with diarrhea cases (OR=3.656, 95%CI: 1.719‒7.778) were the possible cause of the outbreak. The SEIR model (r₀=5, α=0.3, β₁=0.08, β₂=0.04) was constructed using prison inmates as susceptible population, aiming at fitting the initial transmission trend of the outbreak, and the epidemic rate declined rapidly after intervention measures were implemented (r_t≈0). ConclusionThis rare rotavirus infection diarrhea outbreak among adults in confined settings suggests that the construction of public health prevention and control systems in prison may be overlooked. Cross infection during meal processing and distribution in the canteens of such settings is likely to be the cause of the outbreak. Given the potential neglect of public heath system construction in special settings, it is imperative to enhance the surveillance and monitoring of rotavirus and other intestinal multi-pathogens among adults, as well as the construction of public health prevention and control systems in these special settings.

ObjectiveTo elucidate the potential mechanism of modified Sinisan （MSNS） in alleviating anxiety-like behaviors induced by chronic restraint stress （CRS） in mice at the metabolic level based on serum untargeted metabolomics and identify key metabolites and metabolic pathways regulated by MSNS. MethodsSeventy-two male C57BL/6 mice were randomly assigned into six groups： control， model， high-dose （2.4 g·kg^-1） MSNS， medium-dose （1.2 g·kg^-1） MSNS， low-dose （0.6 g·kg^-1） MSNS， and positive control （fluoxetine， 2.6 mg·kg^-1）. Except the control group， the other groups were subjected to CRS for the modeling of anxiety. Mice were administrated with corresponding agents by gavage 2 h before daily restraint for 14 days. Anxiety-like behaviors were evaluated by the open field test （OFT）， elevated plus maze （EPM） test， and light/dark box （LDB） test. Serum levels of corticotropin-releasing hormone （CRH）， adrenocorticotrophic hormone （ACTH）， and corticosterone （CORT） were measured via ELISA to assess stress levels. Ultra-performance liquid chromatography-tandem mass spectrometry （UPLC-MS/MS） was employed to detect 9 metabolites in the brain tissue and serum metabolites. Orthogonal partial least squares-discriminant analysis （OPLS-DA） was adopted to identify differential metabolites （VIP>1.0， P<0.05）. MetaboAnalyst 5.0 was used for metabolic pathway enrichment analysis of the differential metabolites. ResultsCompared with the control group， the model group showed reductions in the central activity time and central distance in the OFT （P<0.05）， the proportions of open-arm residence time and open-arm residence times in the EPM test （P<0.01）， and the proportions of open box activity time and open box activity distance in the LDB test （P<0.05）， which were increased in the medium- and high-dose MSNS groups compared with the model group （P<0.05）. Compared with the control group， the model group showed elevated levels of CRH， ACTH， and CORT in the serum （P<0.01）， and the elevations were diminished in the medium- and high-dose MSNS groups （P<0.05）. UPLC-MS results indicated that compared with the control group， the model group presented declined DA， GABA， 5-HIAA， 5-HT， and 5-HT/Trp levels （P<0.05， P<0.01） and raised Glu， NE， Kyn， and Kyn/Trp levels （P<0.05）. Compared with the model group， high-dose MSNS increased the GABA， 5-HIAA， and 5-HT/Trp levels （P<0.05） and lowered the Glu and Kyn/Trp levels （P<0.05）. Untargeted metabolomics identified that 16 CRS-induced metabolic disturbances were reversed by MSNS. KEGG pathway analysis indicated that MSNS primarily modulated eight core pathways including alanine/aspartate/glutamate metabolism， butyrate metabolism， arginine-proline metabolism， TCA cycle， unsaturated fatty acid biosynthesis， and tryptophan metabolism. The mechanisms involved multidimensional biological processes， including neurotransmitter homeostasis regulation， TCA cycle energy metabolism optimization， and inflammatory response suppression. ConclusionMSNS alleviates CRS-induced anxiety-like behaviors in mice by mitigating hypothalamic-pituitary-adrenal axis hyperactivity， improving hippocampal neurotransmitter and tryptophan metabolic pathways， and regulating alanine/aspartate/glutamate metabolism， butyrate metabolism， arginine-proline metabolism， and TCA cycle.

ObjectiveTo elucidate the potential mechanism of modified Sinisan （MSNS） in alleviating anxiety-like behaviors induced by chronic restraint stress （CRS） in mice at the metabolic level based on serum untargeted metabolomics and identify key metabolites and metabolic pathways regulated by MSNS. MethodsSeventy-two male C57BL/6 mice were randomly assigned into six groups： control， model， high-dose （2.4 g·kg^-1） MSNS， medium-dose （1.2 g·kg^-1） MSNS， low-dose （0.6 g·kg^-1） MSNS， and positive control （fluoxetine， 2.6 mg·kg^-1）. Except the control group， the other groups were subjected to CRS for the modeling of anxiety. Mice were administrated with corresponding agents by gavage 2 h before daily restraint for 14 days. Anxiety-like behaviors were evaluated by the open field test （OFT）， elevated plus maze （EPM） test， and light/dark box （LDB） test. Serum levels of corticotropin-releasing hormone （CRH）， adrenocorticotrophic hormone （ACTH）， and corticosterone （CORT） were measured via ELISA to assess stress levels. Ultra-performance liquid chromatography-tandem mass spectrometry （UPLC-MS/MS） was employed to detect 9 metabolites in the brain tissue and serum metabolites. Orthogonal partial least squares-discriminant analysis （OPLS-DA） was adopted to identify differential metabolites （VIP>1.0， P<0.05）. MetaboAnalyst 5.0 was used for metabolic pathway enrichment analysis of the differential metabolites. ResultsCompared with the control group， the model group showed reductions in the central activity time and central distance in the OFT （P<0.05）， the proportions of open-arm residence time and open-arm residence times in the EPM test （P<0.01）， and the proportions of open box activity time and open box activity distance in the LDB test （P<0.05）， which were increased in the medium- and high-dose MSNS groups compared with the model group （P<0.05）. Compared with the control group， the model group showed elevated levels of CRH， ACTH， and CORT in the serum （P<0.01）， and the elevations were diminished in the medium- and high-dose MSNS groups （P<0.05）. UPLC-MS results indicated that compared with the control group， the model group presented declined DA， GABA， 5-HIAA， 5-HT， and 5-HT/Trp levels （P<0.05， P<0.01） and raised Glu， NE， Kyn， and Kyn/Trp levels （P<0.05）. Compared with the model group， high-dose MSNS increased the GABA， 5-HIAA， and 5-HT/Trp levels （P<0.05） and lowered the Glu and Kyn/Trp levels （P<0.05）. Untargeted metabolomics identified that 16 CRS-induced metabolic disturbances were reversed by MSNS. KEGG pathway analysis indicated that MSNS primarily modulated eight core pathways including alanine/aspartate/glutamate metabolism， butyrate metabolism， arginine-proline metabolism， TCA cycle， unsaturated fatty acid biosynthesis， and tryptophan metabolism. The mechanisms involved multidimensional biological processes， including neurotransmitter homeostasis regulation， TCA cycle energy metabolism optimization， and inflammatory response suppression. ConclusionMSNS alleviates CRS-induced anxiety-like behaviors in mice by mitigating hypothalamic-pituitary-adrenal axis hyperactivity， improving hippocampal neurotransmitter and tryptophan metabolic pathways， and regulating alanine/aspartate/glutamate metabolism， butyrate metabolism， arginine-proline metabolism， and TCA cycle.

The current study aimed to clarify the roles of apolipoprotein A5 (ApoA5) and milk fat globule-epidermal growth factor 8 (Mfge8) in regulating myocardial lipid deposition and the regulatory relationship between them. The serum levels of ApoA5 and Mfge8 in obese and healthy people were compared, and the obesity mouse model induced by the high-fat diet (HFD) was established. In addition, primary cardiomyocytes were purified and identified from the hearts of suckling mice. The 0.8 mmol/L sodium palmitate treatment was used to establish the lipid deposition cardiomyocyte model in vitro. ApoA5-overexpressing adenovirus was used to observe its effects on cardiac function and lipids. The expressions of the fatty acid uptake-related molecules and Mfge8 on transcription or translation levels were detected. Co-immunoprecipitation was used to verify the interaction between ApoA5 and Mfge8 proteins. Immunofluorescence was used to observe the co-localization of Mfge8 protein with ApoA5 or lysosome-associated membrane protein 2 (LAMP2). Recombinant rMfge8 was added to cardiomyocytes to investigate the regulatory mechanism of ApoA5 on Mfge8. The results showed that participants in the simple obesity group had a significant decrease in serum ApoA5 levels (P < 0.05) and a significant increase in Mfge8 levels (P < 0.05) in comparison with the healthy control group. The adenovirus treatment successfully overexpressed ApoA5 in HFD-fed obese mice and palmitic acid-induced lipid deposition cardiomyocytes, respectively. ApoA5 reduced the weight of HFD-fed obese mice (P < 0.05), shortened left ventricular isovolumic relaxation time (IVRT), increased left ventricular ejection fraction (LVEF), and significantly reduced plasma levels of triglycerides (TG) and cholesterol (CHOL) (P < 0.05). In myocardial tissue and cardiomyocytes, the overexpression of ApoA5 significantly reduced the deposition of TG (P < 0.05), transcription of fatty acid translocase (FAT/CD36) (P < 0.05), fatty acid-binding protein (FABP) (P < 0.05), and fatty acid transport protein (FATP) (P < 0.05), and protein expression of Mfge8 (P < 0.05), while the transcription levels of Mfge8 were not significantly altered (P > 0.05). In vitro, the Mfge8 protein was captured using ApoA5 as bait protein, indicating a direct interaction between them. Overexpression of ApoA5 led to an increase in co-localization of Mfge8 with ApoA5 or LAMP2 in cardiomyocytes under lipid deposition status. On this basis, exogenous added recombinant rMfge8 counteracted the improvement of lipid deposition in cardiomyocytes by ApoA5. The above results indicate that the overexpression of ApoA5 can reduce fatty acid uptake in myocardial cells under lipid deposition status by regulating the content and cellular localization of Mfge8 protein, thereby significantly reducing myocardial lipid deposition and improving cardiac diastolic and systolic function.
Animals ; Humans ; Mice ; Myocytes, Cardiac/metabolism* ; Obesity/physiopathology* ; Male ; Apolipoprotein A-V/blood* ; Lipid Metabolism/physiology* ; Milk Proteins/blood* ; Myocardium/metabolism* ; Diet, High-Fat ; Antigens, Surface/physiology* ; Mice, Inbred C57BL ; Cells, Cultured ; Female

The development of bone in human body and the maintenance of bone mass in adulthood are regulated by a variety of biological factors. Myocyte enhancer factor 2C (MEF2C), as one of the many factors regulating bone tissue development and balance, has been shown to play a key role in bone development and metabolism. However, there is limited systematic analysis on the effects of MEF2C on bone tissue. This article reviews the role of MEF2C in bone development and metabolism. During bone development, MEF2C promotes the development of neural crest cells (NC) into craniofacial cartilage and directly promotes cartilage hypertrophy. In terms of bone metabolism, MEF2C exhibits a differentiated regulatory model across different types of osteocytes, demonstrating both promoting and other potential regulatory effects on bone formation, with its stimulating effect on osteoclasts being determined. In view of the complex roles of MEF2C in bone tissue, this paper also discusses its effects on some bone diseases, providing valuable insights for the physiological study of bone tissue and strategies for the prevention of bone diseases.
Humans ; MEF2 Transcription Factors/physiology* ; Bone and Bones/metabolism* ; Animals ; Bone Development/physiology* ; Osteogenesis/physiology* ; Myogenic Regulatory Factors/physiology*

This study aims to investigate the effects of renin inhibitor aliskiren on kidney injury in human angiotensinogen-renin (AGT-REN) double transgenic hypertensive (dTH) mice and explore its possible mechanism. The dTH mice were divided into hypertension group (HT group) and aliskiren intervention group (HT+Aliskiren group), while wild-type C57BL/6 mice were served as the control group (WT group). Blood pressure data of mice in HT+Aliskiren group were collected after 28 d of subcutaneous penetration of aliskiren (20 mg/kg), and the damage of renal tissue structure and collagen deposition were observed by HE, Masson and PAS staining. The ultrastructure of kidney was observed by transmission electron microscope. Coomassie bright blue staining and biochemical analyzer were used to detect renal function injury. The expression of renin-angiotensin system (RAS) was determined by ELISA and immunohistochemistry. The contents of superoxide dismutase (SOD) and malondialdehyde (MDA) in kidney were determined by chemiluminescence method. The content of nicotinamide adenine dinucleotide phosphate (NADPH) oxidase subunit p47^phox, inducible nitric oxide synthase (iNOS), 3-nitrotyrosine (3-NT), NADPH oxidase 2 (NOX2) and NADPH oxidase 4 (NOX4) were detected by Western blot analysis. The results showed that compared with WT group, the blood pressure of mice in HT group was significantly increased. The renal tissue structure in HT group showed glomerular sclerosis, severe interstitial tubular injury, and increased collagen deposition. In addition, 24 h urinary protein, serum creatinine and urea levels increased. Serum and renal tissue levels of angiotensin II (Ang II) were increased, serum angiotensin-(1-7) [Ang-(1-7)] expression was decreased, and renal Ang-(1-7) expression was elevated. The expressions of ACE, Ang II type 1 receptor (AT₁R) and MasR in renal tissue were increased, while the expression of ACE2 was decreased. MDA content increased, SOD content decreased, and the expressions of p47^phox, iNOS, 3-NT, NOX2 and NOX4 were increased. However, aliskiren reduced blood pressure in dTH mice, improved renal structure and renal function, reduced Ang II and Ang-(1-7) levels in serum and renal tissue, reduced the expression of ACE and AT₁R in renal tissue, increased the expression of ACE2 and MasR in renal tissue, and decreased the above levels of oxidative stress indexes in dTH mice. These results suggest that aliskiren may play a protective role in hypertensive renal injury by regulating the balance between ACE-Ang II-AT₁R and ACE2-Ang-(1-7)-MasR axes and inhibiting oxidative stress.
Animals ; Fumarates/therapeutic use* ; Mice ; Renin/antagonists & inhibitors* ; Amides/therapeutic use* ; Mice, Inbred C57BL ; Hypertension/physiopathology* ; Mice, Transgenic ; Kidney/pathology* ; Angiotensinogen/genetics* ; Renin-Angiotensin System/drug effects* ; NADPH Oxidases/metabolism* ; Male ; Antihypertensive Agents/pharmacology* ; Humans ; Superoxide Dismutase/metabolism* ; NADPH Oxidase 4