Magnoflorine Ameliorates Chronic Kidney Disease in High-Fat and High-Fructose-Fed Mice by Promoting Parkin/PINK1-Dependent Mitophagy to Inhibit NLRP3/Caspase-1-Mediated Pyroptosis

Clerodendranthus spicatus-Cordyceps cicadae regulates mitophagy and protects renal tubular epithelial cells from hyperuricemic nephropathy

ETHNOPHARMACOLOGICAL RELEVANCE

Clerodendranthus spicatus (CS) and Cordyceps cicadae (CC) are both medicine and food. They have long been used to treat kidney disease, but their mechanisms for treating hyperuricemic nephropathy (HN) are not yet clear.

AIM

We investigated the effect and mechanism of Clerodendranthus spicatus-Cordyceps cicadae (CS-CC) in HN treatment.

METHODS

We detected the chemical profiling of CS-CC freeze-dried powder, drug-containing serum and drug-containing intracellular fluid by UHPLC-Q Exactive Orbitrap-HRMS. We explored the effective components as well as underlying mechanisms of CS-CC in HN treatment via network pharmacological analysis. We constructed HN rat models induced by gavaging potassium oxonate and uric acid (UA) for three weeks, and performed biochemical and pathological tests as well as histological observation. The expressions of fibrosis-associated proteins were quantitatively analyzed using immunohistochemistry staining and western blot analysis. For in vitro studies, we measured the metabolic fluxes in UA-treated HK-2 cells using Seahorse XFe24 analyzer and flow cytometric analysis. Mitophagy-associated proteins were evaluated using immunofluorescence co-localization analysis and western blot analysis.

RESULTS

A total of 14 simultaneous constituents of CS-CC in vivo and in vitro were identified. Network pharmacological analysis highlighted CS-CC regulated mitophagy in HN. CS-CC treatment effectively enhanced renal function and ameliorate renal fibrosis in HN rats. We found PINK1-mediated mitophagy was suppressed in HN, while CS-CC treatment could restore cellular metabolism, activate mitophagy and protect tubular epithelial cells in HN.

CONCLUSIONS

PINK1-mediated mitophagy was significantly inhibited in HN, whereas CS-CC treatment demonstrated remarkable efficacy in attenuating renal fibrosis and promoting mitophagy to protect tubular epithelial cells in HN.

Dahuang Huanglian Decoction alleviates dysbiosis by inhibiting GBP5/NLRP3 signaling pathway-mediated pyroptosis of colonic epithelial cells

ETHNOPHARMACOLOGICAL RELEVANCE

Currently, the prevalence of dysbiosis is increasing, but its treatment options are limited. Dahuang Huanglian Xiexin Decoction (XXD) is a traditional herbal prescription recorded in the Treatise on Typhoid Fever, with a longstanding application in the treatment of digestive system diseases. It consists mainly of three classical chinese medicinal herbs: Dahuang (Rheum palmatum L.), Huangqin (Scutellaria baicalensis Georgi), and Huanglian (Coptis chinensis Franch.). Previous studies demonstrated the efficacy of XXD in treating dysbiosis. However, the exact underlying mechanism requires further investigation.

AIM OF THE STUDY

The effects of XXD were evaluated in this study to determine its impact on dysbiosis and to reveal the potential mechanisms underlying its alleviation using proteomics and transcriptomics.

MATERIALS AND METHODS

The components of XXD were identified through UPLC-Q-TOF-MS. Dysbiosis mice were established by mixing antibiotic solutions, and XXD was employed as the therapeutic agent in the intervention. Body weight changes, diarrhea rates, and histopathology were evaluated to determine the therapeutic effects of XXD. Proteomics and transcriptomics were subsequently employed to further elucidate the mechanisms underlying the therapeutic effects of XXD on dysbiosis. Meanwhile, TEM was used to observe tight junctions and pyroptosis in the mouse colon. Furthermore, IF, western blotting, RT-qPCR, and ELISA were employed to investigate the mechanism of XXD.

RESULTS

This study indicates that XXD promoted the recovery from dysbiosis and repair of the intestinal barrier. Integrative proteomic and transcriptomic analyses identified the NOD-like receptor signaling pathway as a potential key mechanism, with GBP5 as a possible key protein or gene. In the verification of the prediction results, XXD could significantly inhibit the protein expression of GBP5, NLRP3, ASC, Pro-Caspase1/Cleaved-Caspase1, and N-GSDMD/GSDMD; upregulate the protein levels of ZO-1 and occludin; and reduce the mRNA levels of GBP5 and NLRP3. In addition, it reduced the secretion of IL-1β and IL-18. IF confirmed the co-localization of EpCAM-GSDMD, GBP5-NLRP3, and NLRP3-ASC in colon tissues, whereas TEM suggested that XXD alleviated the ultrastructural damage caused by pyroptosis.

CONCLUSION

This study demonstrated that XXD can repair the intestinal mucosal barrier and regulate dysbiosis and its associated symptoms. Multiomics approaches have been used to predict the potential mechanisms of XXD. Evidence from experiments indicates that the regulation of dysbiosis by XXD may involve alleviating pyroptosis via inhibition of the GBP5/NLRP3 pathway.

Magnoflorine alleviates nonalcoholic fatty liver disease by modulating lipid metabolism, mitophagy and inflammation

BACKGROUND

Nonalcoholic fatty liver disease (NAFLD) is a prevalent liver condition associated with metabolic syndrome, often aggravated by inflammation and mitochondrial dysfunction. This study aims to explore the therapeutic potential of magnoflorine, an alkaloid with known anti-inflammatory properties, in ameliorating NAFLD by modulating mitochondrial autophagy and inhibiting the NLRP3 inflammasome.

METHODS

Male C57BL/6 J mice were fed a high-fat diet (HFD) for 16 weeks to induce NAFLD. Magnoflorine (5 and 10 mg/kg) was administered by gavage daily for 16 weeks. Liver and serum samples were analyzed for lipid profiles, inflammation markers, and autophagy-related proteins, and liver histology was examined to assess changes.

RESULTS

Magnoflorine treatment improved dyslipidemia in NAFLD mice, shown by decreased serum triglycerides, total cholesterol, and LDL-C, and increased HDL-C. Histological analysis showed reduced hepatic steatosis and inflammation, with less lipid droplet accumulation and hepatocyte ballooning. Western blot results indicated upregulation of Parkin and PINK1, and downregulation of NLRP3, ASC, and caspase-1, with lower serum IL-1β levels, reflecting reduced inflammation.

CONCLUSIONS

Magnoflorine offers a promising approach for mitigating NAFLD progression through modulating mitochondrial autophagy and inhibiting inflammation.

Metformin Alleviates Liver Metabolic Dysfunction in Polycystic Ovary Syndrome by Activating the Ethe1/Keap1/PINK1 Pathway

Background: Polycystic ovary syndrome (PCOS) is a reproductive endocrine disease characterized by metabolic abnormalities, with 34-70% of patients with PCOS also presenting non-alcoholic fatty liver disease (NAFLD). Metformin is a first-line treatment for relieving insulin resistance in PCOS; however, the potential therapeutic application of metformin for preventing NAFLD/metabolic dysfunction-associated fatty liver disease (MAFLD) in PCOS remains under-explored. Here, we investigated the potential protective effects and the underlying mechanisms of metformin against hepatic lipid metabolic disorders in prenatal anti-Müllerian hormone (PAMH)-induced PCOS mice. Methods: First, we developed a prenatal AMH-induced PCOS-like model using pregnant C57BL/6N mice. Female offspring of mice were then subjected to the glucose tolerance test and insulin tolerance test pre- and post-treatment with metformin. H&E staining, serum hormone, and biochemical analyses were performed to determine the effects of metformin on metabolic abnormalities and liver damage in the PCOS-like model. To verify the specific mechanism of action of metformin, dehydroepiandrosterone (DHEA) and free fatty acids (FFAs; palmitic acid and oleic acid) induced alpha mouse liver 12 (AML-12) cells were used to establish a mouse liver cell model of adipose-like degeneration and lipid deposition. Results: Metformin effectively alleviated hepatic lipid accumulation in the PCOS mice. Furthermore, mitochondrial dysfunction and loss of redox homeostasis in the liver of PCOS mice were rescued upon metformin administration. Mechanistic insights reveal that metformin regulates mitochondrial autophagy in PCOS liver tissue via the activation of the Ethe1/Keap1/Nrf2/PINK1/Parkin pathway, thereby improving liver recovery in PCOS mice. Conclusions: Our findings highlight the role and mechanism of metformin in ameliorating abnormal mitophagy and lipid metabolic disorders in the PCOS mice livers and the potential of metformin for addressing NAFLD in PCOS mice.

PINK1 link mitochondria-ER contacts controls deposition of intramuscular fat in pigs

Intramuscular fat (IMF) is a key determinant of meat quality in pigs, influencing characteristics such as tenderness, flavor, and marbling. The regulation of IMF deposition involves complex metabolic processes, with mitochondrial function playing a central role. PTEN-induced kinase 1 (PINK1), a protein involved in mitophagy and mitochondrial quality control, has recently been implicated in regulating fat deposition, although its role in IMF deposition in pigs remains unclear. This study investigates how PINK1 regulates IMF deposition by modulating mitochondrial-endoplasmic reticulum (ER) interactions. We utilized single-cell RNA sequencing to demonstrate that PINK1 is predominantly expressed in fibro-adipogenic progenitors (FAPs) and adipocytes, and its expression is negatively correlated with IMF content in multiple pig breeds. Knockdown of PINK1 in vivo led to increased intramuscular triglyceride content and enhanced adipogenic differentiation in primary porcine IMF cells. Additionally, PINK1 depletion resulted in impaired mitochondrial respiration, increased mitochondrial biogenesis, and disruption of mitochondria-ER contacts, further suggesting that PINK1 mediated of mitochondrial function and communication between mitochondria and ER is essential for controlling lipid deposition. These findings provide novel insights into the molecular mechanisms governing IMF accumulation and highlight PINK1 as a potential target for manipulating fat deposition in both agricultural and biomedical contexts.

PINK1 activation by MTK458 ameliorates neurological impairments and pyroptosis after intracerebral hemorrhage in mice

Intracerebral hemorrhage (ICH) is often linked to severe neurological impairments, including cognitive deficits and anxiety-like behaviors. This study aimed to evaluate the therapeutic potential of PTEN-induced kinase 1 (PINK1), which is activated during ICH, as a target for mitigating these effects. C57/BL6 wild-type mice underwent ICH induction through an intrastriatal injection of autologous blood. The PINK1 activator, MTK458, was administered daily doses of 10-50 mg/kg starting one week before ICH induction and continuing for three days post-surgery. The modified neurological severity score (mNSS) was used to assess neurological deficits, while brain edema was measured through brain water content. The open field test and Y-maze test were used to evaluate anxiety-like behavior, and cognitive function respectively. The effects of ICH on cortical cell pyroptosis, Parkin/PINK1-mediated mitophagy, and the activation of the NOD-, LRR- and pyrin domain-containing protein 3 (NLRP3) inflammasome were analyzed via Western blotting, ELISA, and qRT-PCR. MTK458 effectively reduced brain water content in the basal ganglia, ipsilateral cortex, and cerebellum, with improvements in mNSS extending to 14 days post-injury. Additionally, MTK458 alleviated both neurological deficits and anxiety-like behavior in ICH mouse models. It also reversed ICH-induced cortical cell pyroptosis by promoting Parkin/PINK1-mediated mitophagy and inhibiting NLRP3 inflammasome activation, as well as the expression of IL-1β and IL-18. These results suggest that MTK458 effectively reduces neurological impairments, brain edema, and anxiety-related behaviors in mice following ICH, highlighting PINK1 activation as a promising therapeutic strategy for ICH-induced neurological deficits.

Morroniside Ameliorates High-Fat and High-Fructose-Driven Chronic Kidney Disease by Motivating AMPK-TFEB Signal Activation to Accelerate Lipophagy and Inhibiting Inflammatory Response

Studies have substantiated that dietary-fat- and fructose-overconsumption-caused lipid metabolism disorders can trigger renal lipotoxicity to drive the progression of chronic kidney disease (CKD). This study was conducted to evaluate the efficacy of morroniside, a natural active substance extracted from the fruit of Cornus officinalis, in inhibiting the progression of CKD in high-fat and high-fructose-fed mice. Our results showed histological changes such as fatty degeneration of renal tubular cells, tubular dilatation, glomerular fibrosis, and abnormal renal function in the kidneys of high-fat- and high-fructose-fed mice, which was significantly improved after morroniside treatment. Mechanistically, morroniside maintained renal lipid metabolism homeostasis and inhibited NLRP3 inflammatory vesicle activation by activating AMPKα to promote TFEB nuclear translocation-mediated lipophagy. Consistent results were observed in palmitic acid-induced HK-2 cells. Notably, silencing AMPKα or TFEB both reversed the effects of morroniside in promoting lipophagy and inhibiting the activation of inflammatory responses in vivo and in vitro. Therefore, our study provides compelling evidence that morroniside delays CKD progression by promoting AMPK/TFEB-mediated lipophagy and inhibiting NLRP3 inflammasome activation, suggesting that dietary supplementation with morroniside and morroniside-rich foods (such as Cornus officinalis) might be an effective strategy for the prevention of CKD.

Magnoflorine ameliorates cartilage degradation in osteoarthritis through inhibition of mitochondrial reactive oxygen species-mediated activation of the NLRP3 inflammasome

This study investigated the role of magnoflorine (MAG) on cartilage protection in osteoarthritis. In vitro studies showed that MAG decreased the expression of inflammatory factors and inhibited extracellular matrix degradation in lipopolysaccharide- and ATP-stimulated C28/I2 cells. Importantly, MAG reduced the levels of pyroptosis-related proteins, including NLRP3, ASC, cleaved-caspase 1, GSDMD-N, IL-18, and IL-1β. Mechanistically, MAG reduced mtROS production and inhibited the activation of the NF-κB signaling pathway. In vivo study demonstrated that sodium iodoacetate-induced cartilage degradation and inflammatory factor release were reversed by MAG. Overall, MAG could inhibit mtROS-mediated NLRP3 inflammasome activation by suppressing mitochondrial dysfunction to ameliorate osteoarthritis.

CREG1 attenuates intervertebral disc degeneration by alleviating nucleus pulposus cell pyroptosis via the PINK1/Parkin-related mitophagy pathway

Intervertebral disc degeneration (IVDD) is a chronic degenerative disease with a complex pathophysiological mechanism. Increasing evidence suggests that the NOD-like receptor thermal protein domain associated protein 3 (NLRP3)-mediated pyroptosis of nucleus pulposus cells (NPCs) plays a crucial role in the pathological progression of IVDD. Pyroptosis is a novel form of programmed cell death characterized by the formation of plasma membrane pores by gasdermin family proteins, leading to cell swelling, membrane rupture, and the release of inflammatory cytokines, which trigger an inflammatory response. The close relationship between pyroptosis and mitophagy has been previously described in various diseases, but the crosstalk between pyroptosis and mitophagy in IVDD remains unexplored. Cellular repressor of E1A-stimulated genes 1 (CREG1) is a secreted glycoprotein involved in cell differentiation and homeostasis regulation and has been shown to promote lysosomal biogenesis and function. However, the potential role and underlying mechanisms of CREG1 in the progression of IVDD have not yet been reported. In this study, we first observed that CREG1 is downregulated following IVDD and that pyroptosis occurs. Furthermore, CREG1 knockdown inhibited NPC proliferation and exacerbated apoptosis and degeneration. Moreover, we confirmed that CREG1 knockdown induced NLRP3 activation while also leading to mitophagy inhibition and mitochondrial dysfunction in NPCs. CREG1 overexpression ameliorated LPS-induced mitophagy inhibition and mitochondrial dysfunction by promoting PINK1/Parkin-mediated mitophagy, thereby suppressing NLRP3 inflammasome activation. However, these protective effects were reversed by pretreatment with the mitophagy inhibitor cyclosporin A (CsA). In a rat model of IVDD, imaging and histological assessments revealed that CREG1 overexpression effectively alleviated the progression of IVDD. Additionally, CREG1 overexpression reduced the expression of NLRP3, caspase-1, and IL-1β while increasing the expression of collagen II, PINK1 and LC3, delaying the course of IVDD. Overall, this study highlights the importance of the interplay between CREG1-mediated regulation of mitophagy and pyroptosis in the pathogenesis of IVDD, identifying CREG1 as a promising therapeutic target for IVDD treatment.

Advances in research on the impact and mechanisms of pathogenic microorganism infections on pyroptosis

Pyroptosis, also known as inflammatory necrosis, is a form of programmed cell death characterized by the activation of gasdermin proteins, leading to the formation of pores in the cell membrane, continuous cell swelling, and eventual membrane rupture. This process results in the release of intracellular contents, including pro-inflammatory cytokines like IL-1β and IL-18, which subsequently trigger a robust inflammatory response. This process is a crucial component of the body's innate immune response and plays a significant role in combating infections. There are four main pathways through which pathogenic microorganisms induce pyroptosis: the canonical inflammasome pathway, the non-canonical inflammasome pathway, the apoptosis-associated caspase-mediated pathway, and the granzyme-mediated pathway. This article provides a brief overview of the effects and mechanisms of pathogen infections on pyroptosis.