Versican Promotes Cardiomyocyte Proliferation and Cardiac Repair.

BACKGROUND: The adult mammalian heart is incapable of regeneration, whereas a transient regenerative capacity is maintained in the neonatal heart, primarily through the proliferation of preexisting cardiomyocytes. Neonatal heart regeneration after myocardial injury is accompanied by an expansion of cardiac fibroblasts and compositional changes in the extracellular matrix. Whether and how these changes influence cardiomyocyte proliferation and heart regeneration remains to be investigated. METHODS: We used apical resection and myocardial infarction surgical models in neonatal and adult mice to investigate extracellular matrix components involved in heart regeneration after injury. Single-cell RNA sequencing and liquid chromatography-mass spectrometry analyses were used for versican identification. Cardiac fibroblast-specific Vcan deletion was achieved using the mouse strains Col1a2-2A-CreER and Vcanfl/fl. Molecular signaling pathways related to the effects of versican were assessed through Western blot, immunostaining, and quantitative reverse transcription polymerase chain reaction. Cardiac fibrosis and heart function were evaluated by Masson trichrome staining and echocardiography, respectively. RESULTS: Versican, a cardiac fibroblast-derived extracellular matrix component, was upregulated after neonatal myocardial injury and promoted cardiomyocyte proliferation. Conditional knockout of Vcan in cardiac fibroblasts decreased cardiomyocyte proliferation and impaired neonatal heart regeneration. In adult mice, intramyocardial injection of versican after myocardial infarction enhanced cardiomyocyte proliferation, reduced fibrosis, and improved cardiac function. Furthermore, versican augmented the proliferation of human induced pluripotent stem cell-derived cardiomyocytes. Mechanistically, versican activated integrin ß1 and downstream signaling molecules, including ERK1/2 and Akt, thereby promoting cardiomyocyte proliferation and cardiac repair. CONCLUSIONS: Our study identifies versican as a cardiac fibroblast-derived pro-proliferative proteoglycan and clarifies the role of versican in promoting adult cardiac repair. These findings highlight its potential as a therapeutic factor for ischemic heart diseases.

Cas13b-mediated RNA targeted therapy alleviates genetic dilated cardiomyopathy in mice.

BACKGROUND: Recent advances in gene editing technology have opened up new avenues for in vivo gene therapy, which holds great promise as a potential treatment method for dilated cardiomyopathy (DCM). The CRISPR-Cas13 system has been shown to be an effective tool for knocking down RNA expression in mammalian cells. PspCas13b, a type VI-B effector that can be packed into adeno-associated viruses and improve RNA knockdown efficiency, is a potential treatment for diseases characterized by abnormal gene expression. RESULTS: Using PspCas13b, we were able to efficiently and specifically knockdown the mutant transcripts in the AC16 cell line carrying the heterozygous human TNNT2R141W (hTNNT2R141W) mutation. We used adeno-associated virus vector serotype 9 to deliver PspCas13b with specific single guide RNA into the hTNNT2R141W transgenic DCM mouse model, effectively knocking down hTNNT2R141W transcript expression. PspCas13b-mediated knockdown significantly increased myofilament sensitivity to Ca2+, improved cardiac function, and reduced myocardial fibrosis in hTNNT2R141W DCM mice. CONCLUSIONS: These findings suggest that targeting genes through Cas13b is a promising approach for in vivo gene therapy for genetic diseases caused by aberrant gene expression. Our study provides further evidence of Cas13b's application in genetic disease therapy and paves the way for future applicability of genetic therapies for cardiomyopathy.

Effects of acupuncture on regulating the hippocampal inflammatory response in rats exposed to post-traumatic stress disorder.

Data from clinical and experimental studies have verified the efficacy and safety of acupuncture in the treatment of post-traumatic stress disorder (PTSD). However, the concrete mechanism has not been well elucidated. The stress-induced activation of inflammatory response is involved in the development and pathogenesis of PTSD. Here, we aimed to investigate the effects of acupuncture on regulating the hippocampal inflammatory response in rats exposed to PTSD. Forty male rats were randomly divided into control, model, acupuncture and sertraline group. Within 1 day after adaptive feeding, all rats were exposed to single prolonged stress (SPS), except for the rats in the control group. Rats in acupuncture group were exposed to acupuncture intervention at the acupoints of Baihui (GV20) and Yintang (GV29), 20 min once per day for 15 days. Rats in sertraline group were exposed to a suspension of sertraline and distilled water (0.2 mg/ml), once per day for 15 days continuously. Body weight and elevated plus maze experiment were detected at different time-points to evaluate the behavioral changes of rats. HE staining method was used to observe the basic pathological morphological changes in hippocampus. Immunofluorescence staining method was used to observe the activation of hippocampal microglia. The content of IL-6 and IL-1ß in serum were detected by ELISA method. Compared with the control group, the body weight of rats in model group significantly decreased on 8 days, and the percentage of time in open arms and open arm entries decreased significantly on 15 days after SPS procedures, which indicated that SPS induced PTSD-like behavior in rats. Acupuncture exerted therapeutic effect. Simultaneously, the result of HE staining confirmed that SPS induced hippocampal morphological changes in SPS rats. Notably, acupuncture reversed the reduction and pathological injury to some extent. The results have also shown that acupuncture intervention effectively reversed the activated microglia of the hippocampus in rats. Moreover, the expression of IL-1ß in serum was significantly decreased by acupuncture intervention. In summary, the present study demonstrated that the role of acupuncture in eliminating PTSD-like behavior might be connected with reversing the pathological process of the inflammatory response mediated by the activation of microglia induced by SPS.

Serum NLRP3 Inflammasome and BDNF: Potential Biomarkers Differentiating Reactive and Endogenous Depression.

Background: The highly heterogeneous pathogenesis of depression and limited response to current antidepressants call for more objective evidence for depression subtypes. Reactive and endogenous depression are two etiologically distinct subtypes associated with different treatment responses. This study aims to explore the potential biomarkers that differentiate reactive and endogenous depressions. Methods: The clinical manifestations and biological indicators of 64 unmedicated mild-to-moderate depression patients (32 reactive depression patients and 32 endogenous depression patients) and 21 healthy subjects were observed. The 24-item Hamilton rating scale for depression (HAMD-24) was used to evaluate the severity of depression. Serum levels of depression-related biological indicators were measured by using the enzyme-linked immunosorbent assay. Results: The NLRP3 level of reactive depression was significantly lower than those of endogenous depression and healthy controls. There was a significant negative correlation between the BDNF level and the HAMD-24 total scores for patients with reactive depression. Conclusion: Our findings suggested the serum NLRP3 and BDNF levels could be potential biomarkers for detecting and evaluating the severity of reactive depression.

Antidepressant effect of electroacupuncture on modulating the expression of c-Fos/AP-1 through the JNK signaling pathway.

The effectiveness and safety of electroacupuncture (EA) for depression have been identified by abundant clinical trials and experimental findings. The c-Jun-NH(2)-terminal kinase (JNK) signaling pathway is considered to be involved in the antidepressant mechanism of EA. However, the antidepressant effect of EA via modulating the expression of c-Fos/activator protein-1 (AP-1) under the condition of JNK inhibition remains unexplored. In this study, we investigated the antidepressant effect and possible mechanism of EA in regulating the expression of c-Fos/AP-1 under the condition of JNK inhibition by SP600125 in rats exposed to chronic unpredictable mild stress (CUMS). The depression-like behaviors were evaluated by the body weight, sucrose preference test (SPT), and open field test (OFT). The expression levels of c-Jun in the hypothalamus, c-Fos in the pituitary gland, and c-Fos and AP-1 in the serum of CUMS induced rat model of depression were detected by ELISA. The results indicated that treatment with EA and fluoxetine can reverse the CUMS-induced depression-like behaviors in rats and can up-regulate the expression levels of c-Jun in the hypothalamus, c-Fos in the pituitary gland, and c-Fos and AP-1 in the serum. Of note, the data demonstrated that SP600125, the inhibitor of JNK signaling pathway, can exert synergistic effect with EA in regulating CUMS-induced abnormal activation of the JNK signaling pathway. The antidepressant effect of EA might be mediated by modulating the expression of c-Fos/AP-1.

FKBP51 induces p53-dependent apoptosis and enhances drug sensitivity of human non-small-cell lung cancer cells.

Lung cancer is one of the most prevalent cancer types worldwide, and non-small-cell lung cancer (NSCLC) accounts for ~85% of all lung cancer cases. Despite the notable prevalence of NSCLC, the mechanisms underlying its progression remain unclear. The present study investigated the involvement of FK506-binding protein 51 (FKBP51) in NSCLC development and determined the factors associated with FKBP51 modification for NSCLC treatment. Immunohistochemical analysis was performed to analyze FKBP51 expression in human NSCLC tissue samples. Additionally, flow cytometry was performed to observe the apoptosis of FKBP51-overexpressing A549 cells. A dual-luciferase reporter assay was performed to confirm the association between FKBP51 and p53 expression, and western blotting was performed to analyze the effects of FKBP51 on the p53 signaling pathway. Finally, cell viability was measured using a Cell Counting Kit-8 assay. The results suggested FKBP51 downregulation in human lung cancer. Furthermore, apoptosis rates may be increased in FKBP51-overexpressing A549 cells. Moreover, FKBP51 promoted p53 expression and subsequent p53 signaling pathway activation. These results indicated that FKBP51 promoted A549 cell apoptosis via the p53 signaling pathway. Additionally, FKBP51 enhanced the sensitivity of A549 cells to cisplatin. Collectively, these data suggested that FKBP51 could serve as a biomarker for human lung cancer and can thus be tailored for incorporation into NSCLC therapy in the future.

[Acupuncture improved depressive behavior by regulating expression of hippocampal apoptosis-related factors in psychological stress-induced depression rats].

OBJECTIVE: To investigate the effect of acupuncture on behavior changes and the expression of reactive oxygen species (ROS), cytochrome C, cysteine-containing aspartate-specific proteases-3 (caspase-3), apoptosis inducing factor (AIF) in the hippocampus of rats exposed to chronic restraint stress (CRS), so as to provide experimental evidence for the prevention and treatment of depression. METHODS: Thirty two male SD rats were equally randomized into control, model, acupuncture and medication (Fluoxetine) groups according to the random number table. The depression model was established by chronic psychological stress stimulation (fasting, water deprivation, chronic restraint combined with solitary raising for 28 days). Manual acupuncture stimulation (2 circles/s) was applied to "Baihui" (GV20), "Yintang" (GV29) and bilateral "Sanyinjiao" (SP6) for 2 min, followed by retaining the needles for 20 min. Rats in the medication group were treated by gavage of Fluoxetine (0.18 mg/mL, 1 mL/100 g body weight). The treatment was conducted once daily for 28 days. The depression-like behavior was evaluated by using open-field test, sucrose preference test, and body weight. The content of ROS of the right hippocampus tissue was detected by using dichloro-dihydro-fluorescein diacetate (DCFH-DA) assay, and the expression levels of cytochrome C, caspase-3 and AIF proteins of hippocampus were determined by using Western blot. RESULTS: After 28 days' stress procedure, the depression rats in the model group showed a significant decrease in the numbers of crossing and rearing of open-field test, sucrose preference index and the body weight compared to the control group (P<0.01). The content of ROS and expression levels of cytochrome C, caspase-3 and AIF in the hippocampus of the model group were significantly increased relevant to the control group (all P<0.01). After the intervention and compared with the model group, the decreased levels of the numbers of crossing and rearing, body weight and sucrose preference index, and the up-regulated levels of content of ROS and expression of cytochrome C, caspase-3 and AIF proteins were all reversed in both acupuncture and medication groups (P<0.01，P<0.05), displaying an anti-depressant effect. The effect of acupuncture was significantly superior to that of medication in up-regulating the numbers of crossing and rearing (P<0.01, P<0.05), and in down-regulating the expression of caspase-3 (P<0.01). No significant differences were found between the medication and acupuncture groups in increasing the body weight and sucrose preference index, and in down-regulating the expression of cytochrome C and AIF proteins (P>0.05). CONCLUSION: Acupuncture intervention can significantly reduce ROS content and expression level of cytochrome C, caspase-3 and AIF proteins in the hippocampus possibly by inhibiting the chronic psychological stress-hippocampal oxidative stress-mitochondrial apoptotic pathway in psychological stress-induced depression rats, which may contribute to its effect in relieving depression.