Farnesoid X receptor (FXR) is a promising target for nonalcoholic steatohepatitis (NASH) and fibrosis. Although various FXR agonists have shown anti-fibrotic effects in diverse preclinical animal ...models, the response rate and efficacies in clinical trials were not optimum. Here we report that prophylactic but not therapeutic administration of obeticholic acid (OCA) prevents hepatic stellate cell (HSC) activation and fibrogenesis. Activated HSCs show limited response to OCA and other FXR agonists due to enhanced FXR SUMOylation. SUMOylation inhibitors rescue FXR signaling and thereby increasing the efficacy of OCA against HSC activation and fibrosis. FXR upregulates Perilipin-1, a direct target gene of FXR, to stabilize lipid droplets and thereby prevent HSC activation. Therapeutic coadministration of OCA and SUMOylation inhibitors drastically impedes liver fibrosis induced by CCl
, bile duct ligation, and more importantly NASH. In conclusion, we propose a promising therapeutic approach by combining SUMOylation inhibitors and FXR agonists for liver fibrosis.
Cholestasis is a common complication of sepsis, and the increased plasma levels of bile acids are predictive of sepsis-associated mortality. However, the exact mechanism by which cholestasis ...aggravates sepsis development remains elusive. Here, we show that bile acids are danger-associated molecular patterns (DAMPs) that can activate both signal 1 and 2 of the NLRP3 inflammasome in inflammatory macrophages. Mechanistically, bile acids induce a prolonged calcium influx and activate the NLRP3 inflammasome synergistically with ATP. Experimental cholestasis sensitizes, while cholestyramine, a bile acid sequestrant, protects mice from LPS-induced sepsis. FXR negatively regulates the NLRP3 inflammasome via physical interaction with NLRP3 and caspase 1. Fxr-null mice are more sensitive, while FXR-overexpressing mice are more resistant, to endoxemia shock. These findings suggest that bile acids and FXR play pivotal roles in sepsis via controlling the NLRP3 inflammasome, and that targeting FXR may represent a therapeutic strategy for cholestasis-associated sepsis.
Dietary patterns and psychosocial factors, ubiquitous part of modern lifestyle, critically shape the gut microbiota and human health. However, it remains obscure how dietary and psychosocial inputs ...coordinately modulate the gut microbiota and host impact. Here, we show that dietary raffinose metabolism to fructose couples stress-induced gut microbial remodeling to intestinal stem cells (ISC) renewal and epithelial homeostasis. Chow diet (CD) and purified diet (PD) confer distinct vulnerability to gut epithelial injury, microbial alternation and ISC dysfunction in chronically restrained mice. CD preferably enriches Lactobacillus reuteri, and its colonization is sufficient to rescue stress-triggered epithelial injury. Mechanistically, dietary raffinose sustains Lactobacillus reuteri growth, which in turn metabolizes raffinose to fructose and thereby constituting a feedforward metabolic loop favoring ISC maintenance during stress. Fructose augments and engages glycolysis to fuel ISC proliferation. Our data reveal a diet-stress interplay that dictates microbial metabolism-shaped ISC turnover and is exploitable for alleviating gut disorders.
Apigenin is a non-toxic natural flavonoid that is abundantly present in common fruits and vegetables. It has been reported that apigenin has various beneficial health effects such as ...anti-inflammation and chemoprevention. Multiple studies have shown that inflammation is an important risk factor for atherosclerosis, diabetes, sepsis, various liver diseases, and other metabolic diseases. Although it has been long realized that apigenin has anti-inflammatory activities, the underlying functional mechanisms are still not fully understood.
In the present study, we examined the effect of apigenin on LPS-induced inflammatory response and further elucidated the potential underlying mechanisms in human THP-1-induced macrophages and mouse J774A.1 macrophages. By using the PrimePCR array, we were able to identify the major target genes regulated by apigenin in LPS-mediated immune response. The results indicated that apigenin significantly inhibited LPS-induced production of pro-inflammatory cytokines, such as IL-6, IL-1β, and TNF-α through modulating multiple intracellular signaling pathways in macrophages. Apigenin inhibited LPS-induced IL-1β production by inhibiting caspase-1 activation through the disruption of the NLRP3 inflammasome assembly. Apigenin also prevented LPS-induced IL-6 and IL-1β production by reducing the mRNA stability via inhibiting ERK1/2 activation. In addition, apigenin significantly inhibited TNF-α and IL-1β-induced activation of NF-κB.
Apigenin Inhibits LPS-induced Inflammatory Response through multiple mechanisms in macrophages. These results provided important scientific evidences for the potential application of apigenin as a therapeutic agent for inflammatory diseases.
Matrine is a well-known anti-inflammatory quinolizidine alkaloid derived from leguminous plant Sophora flavescens Ait. (Leguminosae).
This study was designed to uncover the potential application of ...matrine in treating spinal cord injury (SCI).
Neuron-like PC12 cells in experimental groups were pre-treated with/without matrine (200 μM) for 24 h and then stimulated by lipopolysaccharide (LPS, 5 μg/mL) for 12 h. PC12 cells in control group were cultured in complete medium. CCK-8 assay, flow cytometry, qRT-PCR, western blot and ELISA were performed to evaluate cell damage. Moreover, after cells were transfected with miR-9 inhibitor for 48 h, above indicators were tested again. qRT-PCR and western blot were also conducted to uncover the downstream effectors and signalling pathways for matrine.
LPS (5 μg/mL) decreased cell viability about 50%. Matrine (200 μM) decreased cell viability about 0%, 13.8% and 30% at 24 h, 48 h and 72 h, respectively. The loss of viability, stimulation of apoptosis, and release of pro-inflammatory cytokines (IL-1β, IL-6, and TNF-α) evoked by LPS were attenuated by the pre-treatment of matrine partly. Meanwhile, LPS reduced miR-9 expression about 60%, but matrine completely reversed LPS-decreased miR-9 level. By silencing miR-9 expression, the protective properties of matrine towards PC12 cells were impeded. Besides, matrine inhibited the activation of JNK and NF-κB pathways even under the condition of LPS. And the impact of matrine on the signalling were attenuated by miR-9 silencing.
This paper provided in vitro evidence that matrine was able to protect PC12 cells against LPS-evoked damage. The neuroprotective properties of matrine may be due to its regulation of miR-9 expression as well as JNK and NF-κB pathways.
Farnesoid X receptor (FXR), a nuclear receptor mainly expressed in enterohepatic tissues, is a master for bile acid, lipid and glucose homeostasis. Additionally, it acts as a cell protector with ...unclear mechanism but may be implicated in combating against inflammation, fibrosis and cancers. FXR is thus accepted as a promising target particularly for the enterohepatic diseases, and numerous FXR modulators have been patented and developed.
This review provides an update on the development of FXR modulators for enterohepatic diseases and offers an in-depth perspective on new strategies for the development of novel FXR modulators.
Despite the development of numerous FXR modulators, which culminated in the successful launch of obeticholic acid (OCA), it remains a matter of debate on how the function of FXR should be exploited for therapeutic purposes. The improvement for obesity achieved by either FXR agonists or antagonists is still in confusion. Whether the side effect of pruritus induced by OCA could be exempted for non-steroidal FXR agonists needs further validation. Apart from the development of conventional FXR ligands, emerging evidence support that restoration of FXR protein level may represent a new strategy in targeting FXR for enterohepatic and metabolic diseases.
Trimethylamine N-oxide (TMAO) is closely related to cardiovascular diseases, particularly heart failure (HF). Recent studies shows that 3,3-dimethyl-1-butanol (DMB) can reduce plasma TMAO levels. ...However, the role of DMB in overload-induced HF is not well understood. In this research study, we explored the effects and the underlying mechanisms of DMB in overload-induced HF. Aortic banding (AB) surgery was performed in C57BL6/J mice to induce HF, and a subset group of mice underwent a sham operation. After surgery, the mice were fed with a normal diet and given water supplemented with or without 1% DMB for 6 weeks. Cardiac function, plasma TMAO level, cardiac hypertrophy and fibrosis, expression of inflammatory, electrophysiological studies and signaling pathway were analyzed at the sixth week after AB surgery. DMB reduced TMAO levels in overload-induced HF mice. Adverse cardiac structural remodeling, such as cardiac hypertrophy, fibrosis and inflammation, was elevated in overload-induced HF mice. Susceptibility to ventricular arrhythmia also significantly increased in overload-induced HF mice. However, these changes were prevented by DMB treatment. DMB attenuated all of these changes by reducing plasma TMAO levels, hence negatively inhibiting the p65 NF-κB signaling pathway and TGF-β1/Smad3 signaling pathway. DMB plays an important role in attenuating the development of cardiac structural remodeling and electrical remodeling in overload-induced HF mice. This may be attributed to the p65 NF-κB signaling pathway and TGF-β1/Smad3 signaling pathway inhibition.
Few medications are available for meeting the increasing disease burden of nonalcoholic fatty liver disease (NAFLD) and its progressive stage, nonalcoholic steatohepatitis (NASH). Traditional herbal ...medicines (THM) have been used for centuries to treat indigenous people with various symptoms but without clarified modern-defined disease types and mechanisms. In modern times, NAFLD was defined as a common chronic disease leading to more studies to understand NAFLD/NASH pathology and progression. THM have garnered increased attention for providing therapeutic candidates for treating NAFLD. In this review, a new model called “multiple organs-multiple hits” is proposed to explain mechanisms of NASH progression. Against this proposed model, the effects and mechanisms of the frequently-studied THM-yielded single anti-NAFLD drug candidates and multiple herb medicines are reviewed, among which silymarin and berberine are already under U.S. FDA-sanctioned phase 4 clinical studies. Furthermore, experimental designs for anti-NAFLD drug discovery from THM in treating NAFLD are discussed. The opportunities and challenges of reverse pharmacology and reverse pharmacokinetic concepts-guided strategies for THM modernization and its global recognition to treat NAFLD are highlighted. Increasing mechanistic evidence is being generated to support the beneficial role of THM in treating NAFLD and anti-NAFLD drug discovery.
This review summarized the role and mechanisms of frequently studied traditional herbs in treating NAFLD. Four frequently studied traditional herbs (silymarin, berberine, curcumin and resveratrol) that are registered in ClinicalTrials.gov preclinically benefits NAFLD/NASH treatment via various molecular pathways including cell death modulation, lipid metabolism modulation, anti-inflammation, anti-oxidative stress, and liver–gut axis. Display omitted
A mild and metal‐free DEAD‐promoted (DEAD = diethyl azodicarboxylate) oxidative Ugi‐type reaction of tertiary amines has been demonstrated. The reaction gives easy access to α‐amino amides and imides ...with diverse functional groups in good isolated yields. This Ugi‐type approach achieves an unprecedented synthesis of α‐amino amide analogues with the assistance of dicarboxylic acids, and not water, for the introduction of the carbonyl oxygen atom of the amide moiety. Mechanistic studies indicated that the dicarboxylic acids may readily undergo an intramolecular annulation, instead of the Mumm rearrangement, to give the desired amide with one molecule of anhydride released.
A new oxidative Ugi‐type reaction promoted by DEAD (diethyl azodicarboxylate) leads to α‐amino imides or amides when mono‐ or dicarboxylic acids, respectively, are used. This metal‐free transformation is highly efficient and has a good tolerance of various functional groups.
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Silybin shows good effects against obesity and metabolic syndrome, but the systemic modulation effect of silybin has not been fully revealed. This study aims to investigate the ...metabolic regulation by silybin of nonalcoholic fatty liver disease (NAFLD). C57BL/6 J mice were fed a high-fat/high-cholesterol diet for 8 weeks and treated with silybin (50 or 100 mg/kg/day) and sodium tauroursodeoxycholate (TUDCA, 50 mg/kg/day) by gavage for the last 4 weeks. Blood biochemical indexes and hepatic lipid measurement as well as Oil red O staining of the liver were conducted to evaluate the model and the lipid-lowering effect of silybin and TUDCA. Furthermore, serum and liver samples were detected by a metabolomic platform based on gas chromatography-mass spectrometry (GC/MS). Multivariate/univariate data analysis and pathway analysis were used to investigate differential metabolites and metabolic pathways. The results showed that the mouse NAFLD model was established successfully and that silybin and TUDCA significantly lowered both serum and hepatic lipid accumulation. Metabolomic analysis of serum and liver showed that a high-fat/high-cholesterol diet caused abnormal metabolism of metabolites involved in lipid metabolism, polyol metabolism, amino acid metabolism, the urea cycle and the TCA cycle. Silybin and TUDCA treatment both reversed metabolic disorders caused by HFD feeding. In conclusion, a high-fat/high-cholesterol diet caused metabolic abnormalities in the serum and liver of mice, and silybin treatment improved hepatic lipid accumulation and modulated global metabolic pathways, which provided a possible explanation of its multiple target mechanism.
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