Coffeeberry Activates the CaMKII/CREB/BDNF Pathway, Normalizes Autophagy and Apoptosis Signaling in Nonalcoholic Fatty Liver Rodent Model

Cav3.2 deletion attenuates nonalcoholic fatty liver disease in mice

Nonalcoholic fatty liver disease (NAFLD) is the most common chronic liver disease and represents the main cause of liver cirrhosis and hepatocellular carcinoma. Cav3.2 is a T-type calcium channel that is widely present in tissues throughout the body and plays a vital role in energy and metabolic balance. However, the effects of Cav3.2 on the NFALD remain unclear. Here, we investigated the role of Cav3.2 channel in the development and progression of NAFLD. After 16 weeks on a high-fat diets (HFD), Cav3.2 knockout (Cav3.2 KO) improved hepatic steatosis, liver injury and metabolic syndrome in an NAFLD mouse model. We provided evidence that Cav3.2 KO inhibited HFD-induced hepatic oxidative stress, inflammation and hepatocyte apoptosis. In addition, Cav3.2 KO also attenuated hepatic lipid accumulation, oxidative stress, inflammation and hepatocyte apoptosis in palmitic acid/oleic acid (PAOA)-treated primary hepatocytes. These results suggest that therapeutic approaches targeting Cav3.2 provide effective approaches for treating NAFLD.

Fanlian Huazhuo Formula alleviates high-fat diet-induced non-alcoholic fatty liver disease by modulating autophagy and lipid synthesis signaling pathway

BACKGROUND

Fanlian Huazhuo Formula (FLHZF) has the functions of invigorating spleen and resolving phlegm, clearing heat and purging turbidity. It has been identified to have therapeutic effects on type 2 diabetes mellitus (T2DM) in clinical application. Non-alcoholic fatty liver disease (NAFLD) is frequently diagnosed in patients with T2DM. However, the therapeutic potential of FLHZF on NAFLD and the underlying mechanisms need further investigation.

AIM

To elucidate the effects of FLHZF on NAFLD and explore the underlying hepatoprotective mechanisms in vivo and in vitro.

METHODS

HepG2 cells were treated with free fatty acid for 24 hours to induce lipid accumulation cell model. Subsequently, experiments were conducted with the different concentrations of freeze-dried powder of FLHZF for 24 hours. C57BL/6 mice were fed a high-fat diet for 8-week to establish a mouse model of NAFLD, and then treated with the different concentrations of FLHZF for 10 weeks.

RESULTS

FLHZF had therapeutic potential against lipid accumulation and abnormal changes in biochemical indicators in vivo and in vitro. Further experiments verified that FLHZF alleviated abnormal lipid metabolism might by reducing oxidative stress, regulating the AMPKα/SREBP-1C signaling pathway, activating autophagy, and inhibiting hepatocyte apoptosis.

CONCLUSION

FLHZF alleviates abnormal lipid metabolism in NAFLD models by regulating reactive oxygen species, autophagy, apoptosis, and lipid synthesis signaling pathways, indicating its potential for clinical application in NAFLD.

Phosphorylation: new star of pathogenesis and treatment in steatotic liver disease

Steatotic liver disease poses a serious threat to human health and has emerged as one of the most significant burdens of chronic liver disease worldwide. Currently, the research mechanism is not clear, and there is no specific targeted drug for direct treatment. Phosphorylation is widely regarded as the most common type of protein modification, closely linked to steatotic liver disease in previous studies. However, there is no systematic review to clarify the relationship and investigate from the perspective of phosphorylation. Phosphorylation has been found to mainly regulate molecule stability, affect localization, transform molecular function, and cooperate with other protein modifications. Among them, adenosine 5'-monophosphate-activated protein kinase (AMPK), serine/threonine kinase (AKT), and nuclear factor kappa-B (NF-kB) are considered the core mechanisms in steatotic liver disease. As to treatment, lifestyle changes, prescription drugs, and herbal ingredients can alleviate symptoms by influencing phosphorylation. It demonstrates the significant role of phosphorylation as a mechanism occurrence and a therapeutic target in steatotic liver disease, which could be a new star for future exploration.

Fenofibrate improves hepatic steatosis, insulin resistance, and shapes the gut microbiome via TFEB-autophagy in NAFLD mice

Non-alcoholic fatty liver disease (NAFLD) is a major liver disease subtype worldwide, is commonly associated with insulin resistance and obesity. NAFLD is characterized by an excessive hepatic lipid accumulation, as well as hepatic steatosis. Fenofibrate is a peroxisome proliferator-activated receptor α agonist widely used in clinical therapy to effectively ameliorate the development of NAFLD, but its mechanism of action is incompletely understood. Here, we found that fenofibrate dramatically modulate the gut microbiota composition of high-fat diet (HFD)-induced NAFLD mouse model, and the change of gut microbiota composition is dependent on TFEB-autophagy axis. Furthermore, we also found that fenofibrate improved hepatic steatosis, and increased the activation of TFEB, which severed as a regulator of autophagy, thus, the protective effects of fenofibrate against NAFLD are depended on TFEB-autophagy axis. Our study demonstrates the host gene may influence the gut microbiota and highlights the role of TFEB and autophagy in the protective effect of NAFLD. This work expands our understanding of the regulatory interactions between the host and gut microbiota and provides novel strategies for alleviating obesity.

Dysfunction of inhibitory interneurons contributes to synaptic plasticity via GABABR-pNR2B signaling in a chronic migraine rat model

Background

According to our previous study, the loss of inhibitory interneuron function contributes to central sensitization in chronic migraine (CM). Synaptic plasticity is a vital basis for the occurrence of central sensitization. However, whether the decline in interneuron-mediated inhibition promotes central sensitization by regulating synaptic plasticity in CM remains unclear. Therefore, this study aims to explore the role of interneuron-mediated inhibition in the development of synaptic plasticity in CM.

Methods

A CM model was established in rats by repeated dural infusion of inflammatory soup (IS) for 7 days, and the function of inhibitory interneurons was then evaluated. After intraventricular injection of baclofen [a gamma-aminobutyric acid type B receptor (GABABR) agonist] or H89 [a protein kinase A (PKA) inhibitor), behavioral tests were performed. The changes in synaptic plasticity were investigated by determining the levels of the synapse-associated proteins postsynaptic density protein 95 (PSD95), synaptophysin (Syp) and synaptophysin-1(Syt-1)]; evaluating the synaptic ultrastructure by transmission electron microscopy (TEM); and determining the density of synaptic spines via Golgi-Cox staining. Central sensitization was evaluated by measuring calcitonin gene-related peptide (CGRP), brain-derived neurotrophic factor (BDNF), c-Fos and substance P (SP) levels. Finally, the PKA/Fyn kinase (Fyn)/tyrosine-phosphorylated NR2B (pNR2B) pathway and downstream calcium-calmodulin-dependent kinase II (CaMKII)/c-AMP-responsive element binding protein (pCREB) signaling were assessed.

Results

We observed dysfunction of inhibitory interneurons, and found that activation of GABABR ameliorated CM-induced hyperalgesia, repressed the CM-evoked elevation of synapse-associated protein levels and enhancement of synaptic transmission, alleviated the CM-triggered increases in the levels of central sensitization-related proteins, and inhibited CaMKII/pCREB signaling via the PKA/Fyn/pNR2B pathway. The inhibition of PKA suppressed the CM-induced activation of Fyn/pNR2B signaling.

Conclusion

These data reveal that the dysfunction of inhibitory interneurons contributes to central sensitization by regulating synaptic plasticity through the GABABR/PKA/Fyn/pNR2B pathway in the periaqueductal gray (PAG) of CM rats. Blockade of GABABR-pNR2B signaling might have a positive influence on the effects of CM therapy by modulating synaptic plasticity in central sensitization.

Regulatory Networks, Management Approaches, and Emerging Treatments of Nonalcoholic Fatty Liver Disease

The pathogenesis of NAFLD is complex and diverse, involving multiple signaling pathways and cytokines from various organs. Hepatokines, stellakines, adipokines, and myokines secreted by hepatocytes, hepatic stellate cells, adipose tissue, and myocytes play an important role in the occurrence and development of nonalcoholic fatty liver disease (NAFLD). The nuclear factor kappa-light-chain-enhancer of activated B cells (NF-κB) contributes to the progression of NAFLD by mediating liver inflammation, immune response, hepatocyte death, and later compensatory proliferation. In this review, we first discuss the crosstalk and interaction between hepatokines, stellakines, adipokines, and myokines and NF-κB in NAFLD. The characterization of the crosstalk of NF-κB with these factors will provide a better understanding of the molecular mechanisms involved in the progression of NAFLD. In addition, we examine new expert management opinions for NAFLD and explore the therapeutic potential of silymarin in NAFLD/NASH.