Sacubitril/valsartan attenuates myocardial inflammation, hypertrophy, and fibrosis in rats with heart failure with preserved ejection fraction.

Heart failure with preserved ejection fraction (HFpEF) represents a multifaceted syndrome related to complex pathologic mechanisms. Sacubitril/valsartan (Sac/val) has demonstrated therapeutic efficacy in HFpEF treatment. However, additional research is required to elucidate its pharmacological mechanisms. Accordingly, this study aimed to explore the potential therapeutic effects of Sac/val in HFpEF rats and the underlying molecular mechanisms. In this study, rats with HFpEF were induced by subjecting spontaneously hypertensive rats to a diet rich in fats, salts, and sugars, along with administering streptozotocin. Subsequently, they were administered Sac/val at a daily dosage of 18 mg/kg. Finally, cardiac structure and function were assessed using echocardiography; Hematoxylin and eosin staining and Masson's trichrome staining were employed to evaluate the pathological changes; Quantitative real-time polymerase chain reaction and Western blot analysis were conducted to determine the expression of pertinent mRNA and proteins. Sac/val treatment attenuated left ventricular (LV) remodeling and diastolic dysfunction in HFpEF rats, possibly related to its anti-inflammatory, anti-hypertrophic, and anti-fibrotic efficacy. Mechanistically, Sac/val might inhibit inflammation by down-regulating cell adhesion molecule (intercellular adhesion molecule-1 (ICAM-1) and vascular endothelial cell adhesion molecule-1 (VCAM-1)) expression. Additionally, it blocked the phosphorylation of glycogen synthase kinase 3ß (GSK-3ß) to prevent cardiomyocyte hypertrophy. Furthermore, it effectively suppressed myocardial fibrosis by inhibiting the transforming growth factor-beta1 (TGF-ß1)/Smads pathway. Our findings suggest that Sac/val improved LV remodeling and diastolic dysfunction, potentially attributed to its anti-inflammatory, anti-hypertrophic, and anti-fibrotic effects. These results provide a sound theoretical rationale for the clinical application of Sac/val in patients with HFpEF.

[Vertical Differences in Grassland Bacterial Community Structure During Non- Growing Season in Eastern Ulansuhai Basin].

Grassland is an important part of the regional ecosystem, and its micro ecological structures play key roles in the process of element migration and the evolution of ecological diversity systems. To discover the spatial difference of the grassland soil bacterial community, we collected five total soil samples at 30 cm depth and 60 cm depth in Eastern Ulansuhai Basin in early May (before the beginning of the new growing season, with a minimum influence of human activities and other factors). Based on 16S rRNA gene-based high-throughput sequencing technology, the vertical characteristic of the bacterial community was analyzed in detail. First, Actinobacteriota, Proteobacteria, Chloroflexi, Acidobacteriota, Gemmatimonadota, Planctomycetota, Methylomirabilota, and Crenarchacota all appeared in the 30 cm and 60 cm samples, with the relative contents all being higher than 1%. In addition, there were a total of six phyla, five genera, and eight OTUs in the 60 cm sample with relative contents higher than those in the 30 cm sample. As a result, the relative abundance changes in dominant bacterial phyla, genera, and even OTUs at different sample depths did not correspond to their contribution to the bacterial community structure. Second, because of the unique contribution to the bacterial community structure in 30 cm and 60 cm samples, the norank_f__norank_o__norank_c__norank_p__Armatimonadota and Candidatus_Xiphinematobacter could be utilized as key bacterial genera during ecological system analysis, belonging to the Armatimonadota and Verrucomicrobiota, respectively. Finally, the relative abundances of ko00190, ko00910, and ko01200 were all higher in 60 cm samples than those in 30 cm samples, which showed that through the increase in metabolic function abundance, the relative contents of C, N, and P elements in grassland soil had been reduced with the increase in depth. These results will provide references for further study on the spatial change of bacterial communities in typical grassland.

Targeting epicardial adipose tissue: A potential therapeutic strategy for heart failure with preserved ejection fraction with type 2 diabetes mellitus.

Heart failure with preserved ejection fraction (HFpEF) is a heterogeneous syndrome with various comorbidities, multiple cardiac and extracardiac pathophysiologic abnormalities, and diverse phenotypic presentations. Since HFpEF is a heterogeneous disease with different phenotypes, individualized treatment is required. HFpEF with type 2 diabetes mellitus (T2DM) represents a specific phenotype of HFpEF, with about 45%-50% of HFpEF patients suffering from T2DM. Systemic inflammation associated with dysregulated glucose metabolism is a critical pathological mechanism of HFpEF with T2DM, which is intimately related to the expansion and dysfunction (inflammation and hypermetabolic activity) of epicardial adipose tissue (EAT). EAT is well established as a very active endocrine organ that can regulate the pathophysiological processes of HFpEF with T2DM through the paracrine and endocrine mechanisms. Therefore, suppressing abnormal EAT expansion may be a promising therapeutic strategy for HFpEF with T2DM. Although there is no treatment specifically for EAT, lifestyle management, bariatric surgery, and some pharmaceutical interventions (anti-cytokine drugs, statins, proprotein convertase subtilisin/kexin type 9 inhibitors, metformin, glucagon-like peptide-1 receptor agonists, and especially sodium-glucose cotransporter-2 inhibitors) have been shown to attenuate the inflammatory response or expansion of EAT. Importantly, these treatments may be beneficial in improving the clinical symptoms or prognosis of patients with HFpEF. Accordingly, well-designed randomized controlled trials are needed to validate the efficacy of current therapies. In addition, more novel and effective therapies targeting EAT are needed in the future.

Atractylenolide III ameliorates spinal cord injury in rats by modulating microglial/macrophage polarization.

BACKGROUND: Inflammatory reactions induced by spinal cord injury (SCI) are essential for recovery after SCI. Atractylenolide III (ATL-III) is a natural monomeric herbal bioactive compound that is mainly derived in Atractylodes macrocephala Koidz and has anti-inflammatory and neuroprotective effects. OBJECTIVE: Here, we speculated that ATL-III may ameliorate SCI by modulating microglial/macrophage polarization. In the present research, we focused on investigating the role of ATL-III on SCI in rats and explored the potential mechanism. METHODS: The protective and anti-inflammatory effects of ATL-III on neuronal cells were examined in a rat SCI model and lipopolysaccharide (LPS)-stimulated BV2 microglial line. The spinal cord lesion area, myelin integrity, and surviving neurons were assessed by specific staining. Locomotor function was evaluated by the Basso, Beattie, and Bresnahan (BBB) scale, grid walk test, and footprint test. The activation and polarization of microglia/macrophages were assessed by immunohistofluorescence and flow cytometry. The expression of corresponding inflammatory factors from M1/M2 and the activation of relevant signaling pathways were assessed by Western blotting. RESULTS: ATL-III effectively improved histological and functional recovery in SCI rats. Furthermore, ATL-III promoted the transformation of M1 into M2 and attenuated the activation of microglia/macrophages, further suppressing the expression of corresponding inflammatory mediators. This effect may be partly mediated by inhibition of neuroinflammation through the NF-κB, JNK MAPK, p38 MAPK, and Akt pathways. CONCLUSION: This study reveals a novel effect of ATL-III in the regulation of microglial/macrophage polarization and provides initial evidence that ATL-III has potential therapeutic benefits in SCI rats.

Effect of morroniside on the transcriptome profiles of rat in injured spinal cords.

We have previously reported that morroniside promoted motor activity after spinal cord injury (SCI) in rats. However, the mechanism by which morroniside induces recovery of injured spinal cord (SC) remains unknown. In the current study, RNA sequencing (RNA-seq) was employed to evaluate changes of gene expressions at the transcriptional level of the injured spinal cords in morroniside-administrated rats. Principal component analysis, analysis of enriched Gene Ontology (GO), enrichment analyses Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway, and other bioinformatics analyses were executed to distinguish differentially expressed genes (DEGs). The results of RNA-seq confirmed the anti-inflammatory and anti-apoptotic effects of morroniside on injured SC tissues, and provided the basis for additional research of the mechanisms involving the protective effects of morroniside on SCI.

[Characteristics of Bacterial Community Structure in Wuliangsu Lake During an Irrigation Interval in Hetao Plain].

In order to study the bacterial community composition and corresponding function in Wuliangsu Lake at the end of the Hetao Plain during the irrigation gap period, lake samples were collected in September 2020, and the pH, TN, TP, DIP, DTP, NH4+-N, Chla, EC, SAL, and other indicators were analyzed. The 16S rRNA high-throughput sequencing method was used to explore the attached bacteria and bacterioplankton in 15 samples of the surface water in Wuliangsu Lake. The experimental results showed that:① the alpha diversity Chao and Shannon indices of attached bacteria were greater than that of bacterioplankton, but the median of Shannoneven index was the same. ② In each sampling point, the bacterioplankton of Proteobacteria and Actinobacteria in the top five dominant bacteria phyla were higher than that of attached bacteria, and the abundance of attached bacteria and bacterioplankton of Bacteroidota were staggered. On the contrary, the contents of attached bacteria of Verrucomicrobiota and Cyanobacteria were all higher than that of bacterioplankton. ③ Redundant analysis showed that pH had the most significant effect on dominant attached bacteria, and the effect of conductivity and salinity in dominant bacterioplankton was the most significant. ④ PICRUSt2 function prediction analysis showed that attached bacteria and planktonic bacteria had the strongest metabolic functions, showing abundant metabolic functions. There were 29 nitrogen-related effective KOs and 88 phosphorus-related effective KOs, with the greatest nitrogen-fixing function and strong inorganic phosphorus-dissolving function, and bacterioplankton played a greater role in the two functions.

The neuroprotective role of morroniside against spinal cord injury in female rats.

Spinal cord injury (SCI) is a disabling condition that often leads to permanent neurological deficits without an effective treatment. Reactive oxygen species (ROS) produced during oxidative stress play a vital role in the pathogenesis following SCI. The antioxidant morroniside is the main active component of the Chinese medicine Cornus officinalis. In recent years, it has been reported that morroniside has therapeutic effects on damage to multiple organs mediated by oxidative damage, but the effect of morroniside on SCI has not been reported. The purpose of this study was therefore to assess the therapeutic effect of morroniside on SCI, and to identify its underlying mechanism by direct intragastric administration immediately after SCI. Our study showed that morroniside treatment improved the functional recovery of rats following SCI. This behavioral improvement was associated with the higher survival in neurons and oligodendrocytes following SCI, which increased the capacity of injured spinal cord (SC) to form myelin and repair tissue, eventually contributing to improved neurological outcome. Furthermore, our study found that oxygen free radicals increased and antioxidant enzyme activity decreased in the injured SC. Interestingly, morroniside treatment decreased oxygen free radical levels and increased antioxidant enzyme activities. Together, our results suggested that morroniside may be an effective treatment for improving outcomes following SCI, and that its antioxidant activity may be one of the mechanisms by which morroniside exerts neuroprotective effects on SCI.

VX-765 reduces neuroinflammation after spinal cord injury in mice.

Inflammation is a major cause of neuronal injury after spinal cord injury. We hypothesized that inhibiting caspase-1 activation may reduce neuroinflammation after spinal cord injury, thus producing a protective effect in the injured spinal cord. A mouse model of T9 contusive spinal cord injury was established using an Infinite Horizon Impactor, and VX-765, a selective inhibitor of caspase-1, was administered for 7 successive days after spinal cord injury. The results showed that: (1) VX-765 inhibited spinal cord injury-induced caspase-1 activation and interleukin-1ß and interleukin-18 secretion. (2) After spinal cord injury, an increase in M1 cells mainly came from local microglia rather than infiltrating macrophages. (3) Pro-inflammatory Th1Th17 cells were predominant in the Th subsets. VX-765 suppressed total macrophage infiltration, M1 macrophages/microglia, Th1 and Th1Th17 subset differentiation, and cytotoxic T cells activation; increased M2 microglia; and promoted Th2 and Treg differentiation. (4) VX-765 reduced the fibrotic area, promoted white matter myelination, alleviated motor neuron injury, and improved functional recovery. These findings suggest that VX-765 can reduce neuroinflammation and improve nerve function recovery after spinal cord injury by inhibiting caspase-1/interleukin-1ß/interleukin-18. This may be a potential strategy for treating spinal cord injury. This study was approved by the Animal Care Ethics Committee of Bengbu Medical College (approval No. 2017-037) on February 23, 2017.

Serum exosomal microRNA transcriptome profiling in subacute spinal cord injured rats.

MicroRNAs (miRNAs) are involved in a series of pathology of spinal cord injury (SCI). Although, locally expressed miRNAs have advantages in studying the pathological mechanism, they cannot be used as biomarkers. The "free circulation" miRNAs can be used as biomarkers, but they have low concentration and poor stability in body fluids. Exosomal miRNAs in body fluids have many advantages comparing with free miRNAs. Therefore, we hypothesized that the specific miRNAs in the central nervous system might be transported to the peripheral circulation and concentrated in exosomes after injury. Using next-generation sequencing, miRNA profiles in serum exosomes of sham and subactue SCI rats were analyzed. The results showed that SCI can lead to changes of serum exosomal miRNAs. These changed miRNAs and their associated signaling pathways may explain the pathological mechanism of suacute SCI. More importantly, we found some valuable serum exosomal miRNAs for diagnosis and prognosis of SCI.

CRID3, a blocker of apoptosis associated speck like protein containing a card, ameliorates murine spinal cord injury by improving local immune microenvironment.

BACKGROUND: After spinal cord injury (SCI), destructive immune cell subsets are dominant in the local microenvironment, which are the important mechanism of injury. Studies have shown that inflammasomes play an important role in the inflammation following SCI, and apoptosis-associated speck-like protein containing a card (ASC) is the adaptor protein shared by inflammasomes. Therefore, we speculated that inhibiting ASC may improve the local microenvironment of injured spinal cord. Here, CRID3, a blocker of ASC oligomerization, was used to study its effect on the local microenvironment and the possible role in neuroprotection following SCI. METHODS: Murine SCI model was created using an Infinite Horizon impactor at T9 vertebral level with a force of 50 kdynes and CRID3 (50 mg/kg) was intraperitoneally injected following injury. ASC and its downstream molecules in inflammasome signaling pathway were measured by western blot. The immune cell subsets were detected by immunohistofluorescence (IHF) and flow cytometry (FCM). The spinal cord fibrosis area, neuron survival, myelin preservation, and functional recovery were assessed. RESULTS: Following SCI, CRID3 administration inhibited inflammasome-related ASC and caspase-1, IL-1ß, and IL-18 activation, which consequently suppressed M1 microglia, Th1 and Th1Th17 differentiation, and increased M2 microglia and Th2 differentiation. Accordingly, the improved histology and behavior have also been found. CONCLUSIONS: CRID3 may ameliorate murine SCI by inhibiting inflammasome activation, reducing proinflammatory factor production, restoring immune cell subset balance, and improving local immune microenvironment, and early administration may be a promising therapeutic strategy for SCI.

Effect of VX­765 on the transcriptome profile of mice spinal cords with acute injury.

Previous studies have shown that caspase-1 plays an important role in the acute inflammatory response of spinal cord injury (SCI). VX­765, a novel and irreversible caspase­1 inhibitor, has been reported to effectively intervene in inflammation. However, the effect of VX­765 on genome­wide transcription in acutely injured spinal cords remains unknown. Therefore, in the present study, RNA­sequencing (RNA­Seq) was used to analyze the effect of VX­765 on the local expression of gene transcription 8 h following injury. The differentially expressed genes (DEGs) underwent enrichment analysis of functions and pathways by Gene Ontology and Kyoto Encyclopedia of Genes and Genomes analyses, respectively. Parallel analysis of western blot confirmed that VX­765 can effectively inhibit the expression and activation of caspase­1. RNA­Seq showed that VX­765 treatment resulted in 1,137 upregulated and 1,762 downregulated DEGs. These downregulated DEGs and their associated signaling pathways, such as focal adhesion, cytokine­cytokine receptor interaction, leukocyte transendothelial migration, extracellular matrix­receptor interaction, phosphatidylinositol 3­kinase­protein kinase B, Rap1 and hypoxia inducible factor­1 signaling pathway, are mainly associated with inflammatory response, local hypoxia, macrophage differentiation, adhesion migration and apoptosis of local cells. This suggests that the application of VX­765 in the acute phase can improve the local microenvironment of SCI by inhibiting caspase­1. However, whether VX­765 can be used as a therapeutic drug for SCI requires further exploration. The sequence data have been deposited into the Sequence Read Archive (https://www.ncbi.nlm.nih.gov/sra/PRJNA548970).

Serum exosomal microRNA transcriptome profiling in subacute spinal cord injured rats.

MicroRNAs (miRNAs) are involved in a series of pathology of spinal cord injury (SCI). Although, locally expressed miRNAs have advantages in studying the pathological mechanism, they cannot be used as biomarkers. The "free circulation" miRNAs can be used as biomarkers, but they have low concentration and poor stability in body fluids. Exosomal miRNAs in body fluids have many advantages comparing with free miRNAs. Therefore, we hypothesized that the specific miRNAs in the central nervous system might be transported to the peripheral circulation and concentrated in exosomes after injury. Using next-generation sequencing, miRNA profiles in serum exosomes of sham and subactue SCI rats were analyzed. The results showed that SCI can lead to changes of serum exosomal miRNAs. These changed miRNAs and their associated signaling pathways may explain the pathological mechanism of suacute SCI. More importantly, we found some valuable serum exosomal miRNAs for diagnosis and prognosis of SCI.

Hypoxia amplifies lipopolysaccharide-induced IL-1β expression in macrophages / 基础医学与临床

Objective To investigate the effect of hypoxia on the expression of IL-1βin macrophages.Methods RAW264.7 cells were treated with normoxia(21%O2),hypoxia(2%O2), normoxia(21%O2)plus LPS and hypoxia(2%O2)plus LPS.RT-qPCR was used to detect the mRNA expression of Vegf,Nlrp3 and Il1b.Western blot was used to detect the protein expression of HIF-1α,NLRP3,caspase-1,cleaved caspase-1,Pro-IL-1βand IL-1β.The peritoneal macrophages of Vhlfl/fl/Apoe-/-mice and VhlΔMac/Apoe-/-mice were treated with or without LPS.RT-qPCR was used to detect the mRNA expression of Vhl,Nlrp3,Il1b and Il6.Results Compared with nor-moxia, hypoxia significantly increased mRNA of Vegf, Nlrp3 and Il1b in RAW264.7(P<0.01).Hypoxia increased mRNA and protein of NLRP 3 and IL-1βin RAW264.7 induced with LPS comparing with normoxia(P<0.01).Hypoxia had no effects on the activation of caspase-1 and the subsequent maturation of Pro-IL-1βinduced with LPS in RAW264.7.Compared with Vhlfl/fl/Apoe-/-peritoneal macrophages,VhlΔMac/Apoe-/-peritoneal macro-phages showed significantly increased mRNA levels of Nlrp3,Il1b and Il6 induced with LPS(P<0.05).Conclu-sions Hypoxia amplifies lipopolysaccharide-induced IL-1βexpression in macrophages.