IP3R1-mediated MAMs formation contributes to mechanical trauma-induced hepatic injury and the protective effect of melatonin

Zhizichi decoction alleviates depressive-like behaviors through modulating mitochondria-associated membrane via the IP3R3-GRP75-VDAC1 complex

ETHNOPHARMACOLOGICAL RELEVANCE

Zhizichi Decoction (ZZCD), a traditional Chinese medicine (TCM), is derived from the combination of Gardenia jasminoides J. Ellis [Rubiaceae] and Semen Sojae Praeparatum, a fermented derivative of Glycine max (L.) Merr. [Leguminosae]. ZZCD has demonstrated anti-inflammatory properties and the potential to promote neural plasticity. Neuroinflammation is believed to contribute to the development of depressive symptoms.

AIM OF THE STUDY

This study investigates the potential antidepressant effects of ZZCD, focusing on its role in regulating neuroinflammatory responses and mitochondria-associated membrane (MAM) structure.

MATERIALS AND METHODS

Using high-performance liquid chromatography (HPLC), we identified five active ingredients in ZZCD. We then evaluated its effect in a chronic social defeat stress (CSDS) mouse model. A combination of Network pharmacology analysis, Western-blot, immunostaining, enzyme-linked immunosorbent assay (ELISA), co-immunoprecipitation (CO-IP), mitochondrial transmembrane potential (ΔΨm), and transmission electron microscopy (TEM) was adopted to elucidate the mechanisms by which ZZCD improves MAM structure, inhibits neuroinflammation, and exerts antidepressant effects. Finally, according to the molecular docking results, a GRP75 overexpression viral vector was constructed to manipulate the MAM-related protein GRP75, further validating the mechanism of ZZCD's antidepressant effect.

RESULTS

ZZCD treatment significantly ameliorated depressive-like behaviors induced by CSDS in mice and reversed adverse changes in endoplasmic reticulum (ER) stress, MAM structure, and mitochondria injury. In addition, ZZCD effectively reduced microglial inflammatory activation and suppressed the increased expression of pro-inflammatory cytokines. Finally, the antidepressant effects of ZZCD were primarily mediated through the IP3R3-GRP75-VDAC1 complex, as demonstrated by the overexpression of the GRP75 protein.

CONCLUSION

In summary, ZZCD exerts antidepressant effects in the CSDS model by improving the MAM structure, alleviating neuroinflammation, and enhancing mitochondrial function.

The correlation between mitochondria-associated endoplasmic reticulum membranes (MAMs) and Ca2+ transport in the pathogenesis of diseases

Mitochondria and the endoplasmic reticulum (ER) are vital organelles that influence various cellular physiological and pathological processes. Recent evidence shows that about 5%-20% of the mitochondrial outer membrane is capable of forming a highly dynamic physical connection with the ER, maintained at a distance of 10-30 nm. These interconnections, known as MAMs, represent a relatively conserved structure in eukaryotic cells, acting as a critical platform for material exchange between mitochondria and the ER to maintain various aspects of cellular homeostasis. Particularly, ER-mediated Ca2+ release and recycling are intricately associated with the structure and functionality of MAMs. Thus, MAMs are integral in intracellular Ca2+ transport and the maintenance of Ca2+ homeostasis, playing an essential role in various cellular activities including metabolic regulation, signal transduction, autophagy, and apoptosis. The disruption of MAMs observed in certain pathologies such as cardiovascular and neurodegenerative diseases as well as cancers leads to a disturbance in Ca2+ homeostasis. This imbalance potentially aggravates pathological alterations and disease progression. Consequently, a thorough understanding of the link between MAM-mediated Ca2+ transport and these diseases could unveil new perspectives and therapeutic strategies. This review focuses on the changes in MAMs function during disease progression and their implications in relation to MAM-associated Ca2+ transport.

Underlying Mechanisms behind the Brain-Gut-Liver Axis and Metabolic-Associated Fatty Liver Disease (MAFLD): An Update

Metabolic-associated fatty liver disease (MAFLD) includes several metabolic dysfunctions caused by dysregulation in the brain-gut-liver axis and, consequently, increases cardiovascular risks and fatty liver dysfunction. In MAFLD, type 2 diabetes mellitus, obesity, and metabolic syndrome are frequently present; these conditions are related to liver lipogenesis and systemic inflammation. This study aimed to review the connection between the brain-gut-liver axis and MAFLD. The inflammatory process, cellular alterations in hepatocytes and stellate cells, hypercaloric diet, and sedentarism aggravate the prognosis of patients with MAFLD. Thus, to understand the modulation of the physiopathology of MAFLD, it is necessary to include the organokines involved in this process (adipokines, myokines, osteokines, and hepatokines) and their clinical relevance to project future perspectives of this condition and bring to light new possibilities in therapeutic approaches. Adipokines are responsible for the activation of distinct cellular signaling in different tissues, such as insulin and pro-inflammatory cytokines, which is important for balancing substances to avoid MAFLD and its progression. Myokines improve the quantity and quality of adipose tissues, contributing to avoiding the development of MAFLD. Finally, hepatokines are decisive in improving or not improving the progression of this disease through the regulation of pro-inflammatory and anti-inflammatory organokines.

The micro-743a-3p-GSTM1 pathway is an endogenous protective mechanism against alcohol-related liver disease in mice

BACKGROUND AND AIMS

Epidemiological evidence suggests that the phenotype of glutathione S-transferase mu 1 (GSTM1), a hepatic high-expressed phase II detoxification enzyme, is closely associated with the incidence of alcohol-related liver disease (ALD). However, whether and how hepatic GSTM1 determines the development of ALD is largely unclear. This study was designed to elucidate the role and potential mechanism(s) of hepatic GSTM1 in the pathological process of ALD.

METHODS

GSTM1 was detected in the liver of various ALD mice models and cultured hepatocytes. Liver-specific GSTM1 or/and micro (miR)-743a-3p deficiency mice were generated by adenoassociated virus-8 delivered shRNA, respectively. The potential signal pathways involving in alcohol-regulated GSTM1 and GSTM1-associated ALD were explored via both genetic manipulation and pharmacological approaches.

RESULTS

GSTM1 was significantly upregulated in both chronic alcohol-induced mice liver and ethanol-exposed murine primary hepatocytes. Alcohol-reduced miR-743a-3p directly contributed to the upregulation of GSTM1, since liver specific silencing miR-743a-3p enhanced GSTM1 and miR-743a-3p loss protected alcohol-induced liver dysfunctions, which was significantly blocked by GSTM1 knockdown. GSTM1 loss robustly aggravated alcohol-induced hepatic steatosis, oxidative stress, inflammation, and early fibrotic-like changes, which was associated with the activation of apoptosis signal-regulating kinase 1 (ASK1), c-Jun N-terminal kinase (JNK), and p38. GSTM1 antagonized ASK1 phosphorylation and its downstream JNK/p38 signaling pathway upon chronic alcohol consumption via binding with ASK1. ASK1 blockage significantly rescued hepatic GSTM1 loss-enhanced disorders in alcohol-fed mice liver.

CONCLUSIONS

Chronic alcohol consumption-induced upregulation of GSTM1 in the liver provides a feedback protection against hepatic steatosis and liver injury by counteracting ASK1 activation. Down-regulation of miR-743a-3p improves alcohol intake-induced hepatic steatosis and liver injury via direct targeting on GSTM1. The miR-743a-3p-GSTM1 axis functions as an innate protective pathway to defend the early stage of ALD.