A molecular phenotypic screen reveals that lobetyolin alleviates cardiac dysfunction in 5/6 nephrectomized mice by inhibiting osteopontin.

BACKGROUND: Cardiovascular diseases are the major cause of mortality in patients with advanced chronic kidney diseases. The predominant abnormality observed among this population is cardiac dysfunction secondary to myocardial remodelings, such as hypertrophy and fibrosis, emphasizing the need to develop potent therapies that maintain cardiac function in patients with end-stage renal disease. AIMS: To identify potential compounds and their targets as treatments for cardiorenal syndrome type 4 (CRS) using molecular phenotyping and in vivo/in vitro experiments. METHODS: Gene expression was assessed using bioinformatics and verified in animal experiments using 5/6 nephrectomized mice (NPM). Based on this information, a molecular phenotyping strategy was pursued to screen potential compounds. Picrosirius red staining, wheat germ agglutinin staining, Echocardiography, immunofluorescence staining, and real-time quantitative PCR (qPCR) were utilized to evaluate the effects of compounds on CRS in vivo. Furthermore, qPCR, immunofluorescence staining and flow cytometry were applied to assess the effects of these compounds on macrophages/cardiac fibroblasts/cardiomyocytes. RNA-Seq analysis was performed to locate the targets of the selected compounds. Western blotting was performed to validate the targets and mechanisms. The reversibility of these effects was tested by overexpressing Osteopontin (OPN). RESULTS: OPN expression increased more remarkably in individuals with uremia-induced cardiac dysfunction than in other cardiomyopathies. Lobetyolin (LBT) was identified in the compound screen, and it improved cardiac dysfunction and suppressed remodeling in NPM mice. Additionally, OPN modulated the effect of LBT on cardiac dysfunction in vivo and in vitro. Further experiments revealed that LBT suppressed OPN expression via the phosphorylation of c-Jun N-terminal protein kinase (JNK) signaling pathway. CONCLUSIONS: LBT improved CRS by inhibiting OPN expression through the JNK pathway. This study is the first to describe a cardioprotective effect of LBT and provides new insights into CRS drug discovery.

Zhen-Wu decoction and lactiflorin, an ingredient predicted by in silico modelling, alleviate uremia induced cardiac endothelial injury via Nrf2 activation.

ETHNOPHARMACOLOGICAL RELEVANCE: Cardiorenal syndrome type 4 (CRS type 4), with high rates of morbidity and mortality, has become a social and economic problem worldwide over the last few decades. Zhen-Wu decoction, a traditional medicine used in East Asia, has been widely used in the treatment of cardiovascular disease and kidney disease, and has shown potential therapeutic effects for the clinical treatment of CRS type 4. However, the underlying mechanism has not been extensively explored. AIM OF THE STUDY: The purpose of this study was to investigate the effect and underlying mechanism of Zhen-Wu decoction on uremic cardiomyopathy, offering a potential target for clinical treatment of CRS type 4. MATERIALS AND METHODS: Five/six nephrectomized mice were utilized for experiments in vivo. The cardioprotective effects of Zhen-Wu decoction were evaluated by echocardiography and tissue staining. RNA-Seq data were used to investigate the potential pharmacological mechanism. The prediction of targets and active components was based on our previous strategy. Subsequently, the protective effect of the selected compound was verified in experiments in vitro. RESULTS: Zhen-Wu decoction alleviated cardiac dysfunction and endothelial injury in 5/6 nephrectomized mice, and the mechanism may involve the inflammatory process and oxidative stress. The activation of the Nrf2 signaling pathway was predicted to be a potential target of Zhen-Wu decoction in protecting endothelial cells. Through our machine learning strategy, we found that lactiflorin as an ingredient in Zhen-Wu decoction, alleviates IS-induced endothelial cell injury by blocking Keap1 and activating Nrf2. CONCLUSIONS: The present study demonstrated that Zhen-Wu decoction and lactiflorin could protect endothelial cells against oxidative stress in mice after nephrectomy by activating the Nrf2 signaling pathway.

Infiltration of invariant natural killer T cells occur and accelerate brain infarction in permanent ischemic stroke in mice.

Invariant natural killer T (iNKT) cells are a unique subset of T cells that have been implicated in inflammation, atopy, autoimmunity, infections, and cancer. Although iNKT cells have been extensively studied over the past decade, its role in the pathogenesis of ischemic brain injury is still largely unknown. In our study, we determined whether iNKT cells infiltration occur in a mouse model of permanent cerebral ischemia. C57BL6/J male mice were treated with either alpha-galactosylceramide (α-GalCer) or vehicle control before undergoing permanent middle cerebral artery occlusion (pMCAO). α-GalCer, a glycolipid antigen, specifically activates iNKT cells by a CD1d-restricted mechanism. Using flow cytometry, 10,000 leukocytes (CD45 high cells) from the ischemic hemisphere and peripheral blood respectively were analyzed to determine the number of NK1.1+CD3+ cells at 3, 12, 24 and 48h post-pMCAO. Cerebral infarct size, brain edema and morphological characteristics were measured at the stipulated time points by 2,3,5-triphenyltetrazolium chloride (TTC) staining, weighing, and H&E staining. The levels of IFN-γ and TNF-α in brain tissue and serum were assessed by immunohistochemistry and ELISA respectively. We found that the number of iNKT cells started increasing from 12h (PB sample) and 24h (ischemic hemisphere sample) respectively in the vehicle treated group. iNKT cells infiltration occurred at an earlier time-point compared in the α-GalCer treated group (T=3H vs T=12H in PB sample; T=12H vs T=24H in ischemic hemisphere sample). Brain water content at 12h and 24h was significantly higher in pMCAO+α-GalCer mice compared to pMCAO+vehicle mice which was in turn higher than mice that underwent sham surgery. Aggravated morphological abnormalities in HE-stained neurons and significantly increased neurons with pyknotic nuclei and cavitation in the ischemic region were observed at 24h in the pMCAO+α-GalCer and pMCAO+vehicle groups. Cerebral infarct volume, neurological deficit Scores and brain edema were significantly increased at 24h in the pMCAO+α-GalCer group compared to pMCAO+vehicle group. In the pMCAO+vehicle group, the serum concentrations of TNF-α and IFN-γ were increased at 12h and 24h post-pMCAO, and remained elevated up to 48h. In mice treated with pMCAO+α-GalCer, TNF-α and IFN-γ were both increased at 12h post-pMCAO, and remained elevated up to 48h. Immunohistochemistry showed that protein expression of TNF-α and IFN-γ in brain tissues was higher in α-GalCer-treated mice. Our results demonstrate that within 48h of focal permanent cerebral ischemia, iNKT cells infiltrate into the brain and contribute to brain infarction.

[Expression and function of Cx32 and Cx43 junctions in medically intractable temporal lobe epilepsy in human].

OBJECTIVE: To study the expression of Cx32 and Cx43 in medically intractable temporal lobe epilepsy in human and investigate the pathogenic relationship between gap junctions and seizures. METHODS: The expression of Cx32 and Cx43 was detected by Western blot and immunohistochemistry in 14 consecutive samples of hippocampus from epileptic patients undergoing an amygdalohippocampectomy for the treatment of intractable seizures. During postmortem dissection, 8 samples of hippocampus in nonepileptic patients dying of other diseases were taken as control group. RESULTS: The expression of Cx32 and Cx43 was at a low level in the control group [Cx32: count of positive cell (9.4 +/- 1.1), ratios of gray scale (0.2 +/- 0.1); Cx43: count of positive cell (9.2 +/- 4.7), ratios of gray scale (0.5 +/- 0.2)], but Cx43 and Cx32 appeared to be expressed at a higher level in epileptic patients compared with that of the control group by immunohistochemistry [Cx32: count of positive cell (14.6 +/- 3.4), Cx43: count of positive cell (16.5 +/- 3.1)] (P < 0.01), and their expression significantly increased by Western blot [Cx32: ratios of gray scale (1.5 +/- 0.2), Cx43: ratios of gray scale (1.4 +/- 0.3)] (P < 0.01). Over-expression of Cx32 and Cx43 was found in 14 consecutive samples of hippocampus from epileptic patients. CONCLUSION: Gap junctions play an important role in the occurrence and progression of intractable seizures.