Berberine protects against diabetic kidney disease via promoting PGC-1α-regulated mitochondrial energy homeostasis

Modified Hu-Lu-Ba-Wan Alleviates Early-Stage Diabetic Kidney Disease via Inhibiting Interleukin-17A in Mice

OBJECTIVE

To identify the underlying molecular mechanism of Modified Hu-Lu-Ba-Wan (MHW) in alleviating renal lesions in mice with diabetic kidney disease (DKD).

METHODS

The db/db mice were divided into model group and MHW group according to a random number table, while db/m mice were settled as the control group (n=8 per group). The control and model groups were gavaged daily with distilled water [10 mL/(kg·d)], and the MHW group was treated with MHW [17.8 g/(kg·d)] for 6 weeks. After MHW administration for 6 weeks, indicators associated with glucolipid metabolism and urinary albumin were tested. Podocytes were observed by transmission electron microscopy. Kidney transcriptomics was performed after confirming therapeutic effects of MHW on DKD mice. The relevant target of MHW' effect in DKD was further determined by enzyme-linked immunosorbent assay, Western blot analysis, immunohistochemistry, and immunofluorescence staining.

RESULTS

Compared with the model group, MHW improved glucose and lipid metabolism (P<0.05), and reduced lipid deposition in the kidney. Meanwhile, MHW reduced the excretion of urinary albumin (P<0.05) and ameliorated renal damage. Transcriptomic analysis revealed that the inflammation response, particularly the interleukin-17 (IL-17) signaling pathway, may be responsible for the effect of MHW on DKD. Furtherly, our results found that MHW inhibited IL-17A and alleviated early fibrosis in the diabetic kidney.

CONCLUSION

MHW ameliorated renal damage in DKD via inhibiting IL-17A, suggesting a potential strategy for DKD therapy.

Nrf2-Mediated Ferroptosis Is Involved in Berberine-Induced Alleviation of Diabetic Kidney Disease

Diabetic kidney disease (DKD) is the most common and serious complication of diabetes mellitus. Currently, there is a lack of safe and effective preventive strategies for DKD. The study aimed to explore the preventive effects and potential mechanisms of berberine (BBR) against DKD. In the in vivo experiments, we established a DKD rat model induced by the combination of high-fat diet and streptozotocin to investigate the preventive effect of BBR on DKD. Subsequently, in vitro experiments using human renal tubular epithelial cells (HK-2 cells) were performed to further validate the effect of BBR on renal tubular epithelial cell ferroptosis induced by advanced glycation end products (AGEs). In vivo, we found that BBR improved renal function and attenuated inflammatory cell infiltration, podocyte injury, and iron deposition in renal tissue in DKD rats. In addition, in vitro experiments showed that BBR attenuated HK-2 cell ferroptosis induced by AGEs. We further identified Nrf2 as a direct binding target of BBR by molecular docking and Surface Plasmon Resonance (SPR). Then, immunohistochemistry and Western Blot results demonstrated that BBR could activate the Nrf2 pathway, initiate the endogenous antioxidant system, and inhibit the occurrence of AGEs-induced ferroptosis. Moreover, silencing of Nrf2 by siRNA technology eliminated the protective effect of BBR on AGEs-induced ferroptosis. Collectively, our results supported that BBR could inhibit oxidative stress and ferroptosis by targeting activation of the Nrf2 pathway, thereby delaying the disease progression of DKD, providing a new scientific basis and perspective for the prevention and treatment of DKD.

PRPF19 mediates the proteasomal degradation of VDR to exacerbate ferroptosis in diabetic nephropathy

Ferroptosis, an iron-dependent form of programmed cell death, is closely associated with tubular damage in diabetic nephropathy (DN). Glutathione peroxidase 4 (GPX4) is an important anti-oxidant enzyme, and plays a crucial role in protecting against ferroptosis. However, the regulatory mechanism of GPX4 expression levels in renal tubular epithelial cells (RTECs) remains elusive. This study reveals that ferroptosis occurs in the late-stage of DN, and the GPX4 level is significantly downregulated in DN patients, animal models and cell models. By applying database predictions, luciferase reporter assays and chromatin immunoprecipitation, we find that vitamin D receptor (VDR) transcription factor promotes GPX4 expression and plays a key role in inhibiting ferroptosis of RTECs. VDR knockout exacerbates ferroptosis in RTECs and worsens renal function, while intraperitoneal injection of VDR agonist paricalcitol significantly improves renal injury. Proteomics analysis suggests that E3 ligase PRPF19 mediates ubiquitination degradation of VDR and is an important therapeutic target for DN. Therefore, through molecular docking, targeted fishing technology using high-performance affinity beads, and surface plasmon resonance (SPR), we screen and identify berberine (BBR) as a novel inhibitor of PRPF19, which offers renal protection by inhibiting VDR degradation and tubular ferroptosis. These findings elucidate the role of ferroptosis in DN renal tubular injury, and suggest that PRPF19 is a promising therapeutic target.

Empagliflozin attenuates renal damage in diabetic nephropathy by modulating mitochondrial quality control via Prdx3-PINK1 pathway

In clinical practice, sodium-glucose transporter 2 inhibitor (SGLT2i) reduces the composite renal outcomes in patients with diabetic kidney disease (DKD). However, its effect on regulating renal mitochondria remains unclear. Mitochondrial quality control (MQC) has been identified as a key factor in DKD. Peroxiredoxin3 (Prdx3) serves as a primary antioxidant protein in mitochondria. In this study, we investigated the expression of Prdx3 in patients with DKD, diabetic mice and HK-2 cells exposed to high glucose and explored SGLT2i potential mechanism of action. The results also showed that empagliflozin (Empa) treatment improved proteinuria and ameliorated renal pathological damage. We observed that Empa has an impact on the expression of Prdx3 in diabetic mice and HK-2 cells exposed to high glucose, so does the mitochondrial dynamic proteins and mitophagy-related proteins Mfn2, Drp1, PINK1, Parkin, LC3II, and P62. In vitro experiments after transfected with pcDNA3.1(+)-Prdx3 and siPrdx3 the expression of Mfn2, Drp1, PINK1, Parkin, LC3II, and P62 changed. The expression of PINK1 decreased after the knockdown of Prdx3. Furthermore, the knockdown of PINK1 accelerated the MQC damage and weakened the protective effect of Empa. Because Empa has impacts on Prdx3, which plays a protective role by influencing MQC, we investigated the latent impact of Prdx3 deficiency on renal injury and its molecular mechanism in vivo and in vitro in DKD. Herein, we demonstrate that Empa treatment modulates MQC potentially via Prdx3 through interacting with PINK1.

Tangshenning formula alleviates tubular injury in diabetic kidney disease via the Sestrin2/AMPK/PGC-1α axis: Restoration of mitochondrial function and inhibition of ferroptosis

ETHNOPHARMACOLOGICAL RELEVANCE

Tangshenning (TSN) is a traditional Chinese medicinal formula developed on principles of kidney tonification and collateral unblocking. TSN, formulated from Astragalus mongholicus Bunge, Rheum palmatum L., Ligusticum chuanxiong Hort., and Rosa laevigata Michx., has demonstrated significant clinical efficacy in the treatment of diabetic kidney disease (DKD). Our previous studies have suggested that TSN mitigates tubular injury in DKD by inhibiting ferroptosis, however, the precise molecular targets and mechanistic pathways underlying these effects remain to be fully elucidated.

AIM OF THE STUDY

We investigated whether the Sestrin2/AMPK/PGC-1α axis serves as a key pathway mediating TSN's protective effects against tubular injury in DKD.

METHODS

In vivo, a spontaneous DKD mouse model was developed using KK-Ay mice. In vitro, human tubular epithelial cells (TECs) were used to establish high glucose and ferroptosis models, as well as a Sestrin2 knockdown model for further analysis. Molecular docking was utilized to examine the binding interactions between TSN's key active components and Sestrin2. Colocalization of Sestrin2 and GPX4 was assessed using dual fluorescence staining. Protein expression levels related to the Sestrin2/AMPK/PGC-1α pathway, ferroptosis markers (SLC7A11 and GPX4), and the tubular injury marker KIM-1 were quantified via Western blot analysis. In vivo, DHE staining, TUNEL staining, and ferrous ion content measurement were performed to evaluate ferroptosis levels in renal tissue. In vitro, the BODIPY 581/591 C11 probe and ferrous ion assay were used to assess ferroptosis levels in TECs. MitoSOX staining, JC-1 assay, and ATP level measurements were conducted to evaluate mitochondrial function in TECs.

RESULTS

In vivo, our results demonstrated that TSN improved renal function, alleviated tubular injury, and reduced pathological damage in DKD mice. Furthermore, TSN upregulated the protein expression of the Sestrin2/AMPK/PGC-1α axis and decreased ferroptosis-related markers in the DKD mouse model. Similarly, in vitro, TSN enhanced the expression of the Sestrin2/AMPK/PGC-1α pathway, restored mitochondrial function, and inhibited ferroptosis in TECs under high glucose and ferroptosis-inducing conditions. Additionally, downregulation of Sestrin2 impaired the therapeutic effects of TSN.

CONCLUSION

TSN alleviates tubular injury in DKD by activating the Sestrin2/AMPK/PGC-1α pathway, restoring mitochondrial function, and inhibiting ferroptosis in TECs.

GPR30-driven fatty acid oxidation targeted by ginsenoside Rd maintains mitochondrial redox homeostasis to restore vascular barrier in diabetic retinopathy

Blood-retinal barrier (BRB) breakdown, a pivotal contributor to multiple retinal vascular diseases, manifests as a progressive increase in vascular permeability induced by various pathological stimuli. The functional plasticity of retinal endothelial cells can be intricately shaped by metabolic alteration. However, little is known about the mechanisms through which endothelial metabolic disorders trigger the dissolution of inter-vascular junctions and the selective approaches to targeting metabolic homeostasis. Herein, we identify AMPK-associated fatty acid oxidation (FAO) inhibition as a critical driver of vascular barrier dysfunction via exacerbating redox imbalance. Pharmacological facilitation of FAO by ginsenoside Rd (Rd) suppresses BRB collapse and other secondary retinal damage in diabetic retinopathy (DR). Mechanistically, Rd targets GPR30 to phosphorylate AMPK via the PKA-LKB1-AMPK kinase cascade. The AMPK activation induced by Rd revitalizes hyperglycemia-compromised FAO, and then sustains mitochondrial NADPH regeneration by emphasis on IDH2 at various levels, including substrate supply, transcription, and post-translational modifications. Therefore, Rd alleviates the disruption of BRB integrity driven by mitochondrial oxidative stress, with the vasculoprotection of Rd diminished by GPR30 knockdown and pharmacological attenuation of AMPK. These findings collectively reveal the previously-unanticipated role of endothelial FAO in heightened retinal vascular leakage, and highlight the potential translational application of GPR30 agonism with Rd to mitigate barrier dysfunction, providing a metabolic regulatory therapeutic strategy for DR.

YY1/HIF-1α/mROS positive-feedback loop exacerbates glomerular mesangial cell proliferation in mouse early diabetic kidney disease

Mesangial cells (MCs) are the most active intrinsic cells in the glomerulus. MCs excessively proliferate at the early stage of diabetic kidney disease (DKD), eventually causing glomerular sclerosis and even renal failure; inhibiting glomerular MC proliferation in early DKD is a promising prevention and treatment strategy for early DKD. Our previous study shows that Yin Yang 1 (YY1), a zinc finger protein, is a novel regulator of DKD-induced renal fibrosis. In this study we investigated the role of YY1 in glomerular MC proliferation in DKD in vivo and in vitro. We first showed that YY1 expression levels were significantly increased in the glomerular MCs of DKD patients and db/db mice and in high glucose (HG)-treated SV40-MES13 cells. By using YY1 expression/knockdown plasmids, we confirmed that YY1 contributed to glomerular MC proliferation in vitro. We demonstrated that YY1 upregulated hypoxia-inducible factor-1 alpha (HIF-1α) expression and activity in HG-treated SV40-MES13 cells, leading to overproduction of mROS. Moreover, mROS contributed to positive feedback regulation of YY1/HIF-1α signaling, and the YY1/HIF-1α/mROS positive feedback loop exacerbated glomerular MC proliferation in HG-treated SV40-MES13 cells. In addition, renal-specific YY1 overexpression promoted glomerular MC proliferation in normal mice, whereas renal-specific YY1 knockdown mitigated MC proliferation in early diabetic mice by inactivating HIF-1α/ROS signaling. In conclusion, the YY1/HIF-1α/mROS positive feedback loop might be an attractive therapeutic target for overcoming glomerulosclerosis in early DKD.

Berberine Inhibits Migration and Apoptosis of Rat Podocytes in Diabetic Nephropathy via the Novel lncRNA LOC102549726 Related Pathway

BACKGROUND

Diabetic nephropathy (DN) stands as one of the most severe complications of diabetes. Podocytes injury, particularly its attachment to the lateral glomerular basement membrane, serves as a crucial indicator of DN. Growing evidence suggests that berberine (BBR) can mitigate the onset and progression of DN. However, the molecular mechanisms through which BBR exerts its beneficial effects in the treatment of DN remain incompletely elucidated.

PURPOSE

To explore the underlying mechanisms by which BBR exerts its therapeutic effects in DN.

METHODS

High-throughput lncRNA sequencing on the renal cortex of both the DN model group and the normal SD group was performed to dig for differentially expressed lncRNAs. The expression of LOC102549726 was evaluated using qPCR. The biological functions of LOC102549726 were analyzed in podocyets and DN rats. The bioinformatics techniques, qPCR and WB were used to explore the potential molecular mechanisms.

RESULTS

We found that lncRNA LOC102549726 was highly expressed in renal cortex of DN rats and podocytes subjected to high glucose conditions. Silencing LOC102549726 inhibited migration and apoptosis of podocytes. Mechanistically, LOC102549726 was identified as a facilitator of the expression of EGF and forkhead box O1 (FOXO1). BBR, a known therapeutic agent for DN, exhibited the ability to diminish the level of LOC102549726, EGF and FOXO1 in both DN rats and podocytes.

CONCLUSION

Our findings suggested that BBR suppresses migration and apoptosis of podocytes in DN through targeting the LOC102549726/EGF/FOXO1 axis. This sheds light on a potential therapeutic avenue for mitigating the impact of DN on podocyte function.

p21-Activated Kinase 4 and Ischemic Acute Kidney Injury in Mice and Humans

Background

AKI after ischemia-reperfusion remains a substantial perioperative challenge lacking effective treatment. p21-activated kinase 4 (PAK4), a downstream effector of Rho GTPase, has been explored in hepatic ischemia-reperfusion injury, but its role in renal ischemia-reperfusion is unknown.

Methods

Wild-type and proximal tubule–specific Pak4 knockout mice underwent 25 minutes of ischemia followed by 24 hours of reperfusion injury. Primary tubular cells and human kidney-2 cells were exposed to hypoxia-reoxygenation injury to investigate the in vitro effect of PAK4. Selective degradation of PAK4 was employed using proteolysis-targeting chimera (PROTAC) to ameliorate AKI.

Results

Post–ischemia-reperfusion, the expression of PAK4 was upregulated through hypoxia-inducible factor 1 α in mouse kidneys. Deletion of PAK4 in proximal tubule cells, but not in myeloid cells, significantly mitigated ischemia-reperfusion–induced AKI, as evidenced by decreased levels of BUN, creatinine, tubular necrosis, apoptosis, macrophage infiltration, and lipid accumulation compared with control mice. Further investigation revealed that PAK4 phosphorylated GSH peroxidase 3 (GPx3) at T47, leading to its proteasomal degradation. In addition, pretreatment of mice with the PAK4 PROTAC preserved GPx3 and enhanced fatty acid β-oxidation, thereby protecting against AKI. In kidney tissues from people with a kidney transplant, elevated levels of PAK4 protein and phosphorylation of GPx3 at T47 were observed.

Conclusions

Renal tubular PAK4 contributes to tissue damage during ischemia-reperfusion injury, whereas PAK4 PROTAC mitigates ischemia-reperfusion injury by reducing oxidative stress and promoting fatty acid β-oxidation.

Rostellularia procumbens (L) Nees. extract attenuates adriamycin-induced nephropathy by maintaining mitochondrial dynamics balance via SIRT1/PGC-1α signaling pathway activation

ETHNOPHARMACOLOGICAL RELEVANCE

Rostellularia procumbens (L) Nees. (R. procumbens) is a classical Chinese herbal medicine that has been used for effective treatment of kidney disease for nearly a thousand years in China. Recently, significant progress has been achieved in understanding the abnormal mitochondrial structure and function from chronic kidney disease (CKD). However, the regulatory mechanisms underlying R. procumbens treatment for CKD and its association with dysfunctional mitochondrial function remain elusive.

AIM OF THE STUDY

To study the protective effect of N-butanol extract from R. procumbens (J-NE) on chronic glomerulonephritis (CGN) mice using a mice model and mitochondrial function-related experiments.

MATERIALS AND METHODS

A renal injury mouse model was developed using a single tail vein injection of adriamycin (9 mg/kg). Renal pathology was analyzed through hematoxylin-eosin (HE) staining and transmission electron microscopy (TEM). Cell apoptosis in kidney tissues was analyzed using TUNEL staining. Protein levels were measured via immunohistochemistry (HIF-1α, FN, α-SMA, and Collagen I) and Western blot (Mn-SOD, p-Drp-S637, MFN1, MFN2, OPA1, TFAM, Nrf1, ATP6, SIRT1, and PGC-1α) analysis. UHPLC-MS/MS was used to analyze the presence of bioactive phytocompounds in J-NE.

RESULTS

The results reported that the levels of kidney injury markers (urinary protein, glomerular atrophy, and renal cell apoptosis), mitochondrial dysfunction markers (mitochondrial ultrastructure, Mn-SOD, HIF-1α, FN and α-SMA),mitochondrial dynamic imbalance markers (p-Drp-S637, MFN1, MFN2 and OPA1) and SIRT1/PGC-1α signaling pathway markers (TFAM, Nrf1, ATP6, SIRT1, and PGC-1α) were settled to a significant improvement by the oral administration of J-NE.

CONCLUSIONS

In conclusion, R. procumbens could be able to protect the kidneys from podocyte injury caused mitochondrial dynamics and energy metabolism dysregulation by modulating the SIRT1/PGC-1α signaling pathway.

Probiotic Limosilactobacillus reuteri DSM 17938 Alleviates Acute Liver Injury by Activating the AMPK Signaling via Gut Microbiota-Derived Propionate

Limosilactobacillus reuteri DSM 17938 (L. reuteri DSM 17938) was one of the most widely used probiotics in humans for gastrointestinal disorders, but few studies have investigated its role in drug-induced liver injury (DILI). Here, we evaluated the efficacy of L. reuteri DSM 17938 using a mouse model of DILI induced by triptolide. Pregavage of L. reuteri DSM 17938 for 1 week remarkably lowered hepatic inflammatory cytokines level and oxidative stress, with diminished serum alanine transaminase and aspartate aminotransferase levels. Metabolomics and RT-qPCR analysis confirmed its ability in ameliorating TP-disrupted hepatic fatty acid β oxidation. Genome annotation of L. reuteri showed its ability to modulate energy metabolism. Targeted metabolomics demonstrated that L. reuteri DSM 17938 modified the short fatty acid profiles in cecum, especially enhancing propionate levels. Further experiments found that L. reuteri DSM 17938 can activate AMPK signaling by upregulating gut microbiota-derived propionate level, thus restoring impaired mitochondrial biogenesis and energy supply processes to recover energy homeostasis, which leads to diminished ROS production and oxidative stress injury in hepatocytes. Besides, AMPK inhibitor dorsomorphin abolished all the effects on propionate protecting mitochondria and energy metabolism. This study established probiotic therapy of L. reuteri DSM 17938 as a preventive intervention for DILI in clinical. We also revealed that L. reuteri DSM 17938 can activate AMPK signaling by propionate, facilitating a deeper understanding of the action mechanism of L. reuteri DSM 17938 against acute liver injury and contributing to the development of its postbiotics and wider applications.

Lipidomics-based natural products for chronic kidney disease treatment

Chronic kidney disease (CKD) is by far the most prevalent disease in the world and is now a major global public health problem because of the increase in diabetes, hypertension and obesity. Traditional biomarkers of kidney function lack sensitivity and specificity for early detection and monitoring of CKD progression, necessitating more sensitive biomarkers for early diagnostic intervention. Dyslipidemia is a hallmark of CKD. Advancements in mass spectrometry (MS)-based lipidomics platforms have facilitated comprehensive analysis of lipids in biological samples and have revealed changes in the lipidome that are associated with metabolic disorders, which can be used as new biomarkers for kidney diseases. It is also critical for the discovery of new therapeutic targets and drugs. In this article, we focus on lipids in CKD, lipidomics methodologies and their applications in CKD. Additionally, we introduce novel biomarkers identified through lipidomics approaches and natural products derived from lipidomics for the treatment of CKD. We believe that our study makes a significant contribution to literature by demonstrating that natural products can improve CKD from a lipidomic perspective.

1-Bromopropane induces mitochondrial damage and lipid metabolism imbalance in respiratory epithelial cells through the PGC-1α/PPARα pathway

1-Bromopropane (1-BP) has become a new air pollutant in occupational and living environments due to its advantages in industrial applications and as a representative compound of volatile organic compounds (VOCs). As an irritant, its damaging effects on respiratory epithelium are worthy of further study. This study aimed to explore the damage effects of 1-BP on respiratory epithelial cells and reveal its underlying mechanisms. We found that exposure to 1-BP markedly reduced the viability of respiratory epithelial cells in a dose-dependent manner, and induced oxidative stress and vacuolation changes in respiratory epithelial cells. Subsequently, through RNA-seq analysis, we identified that the 1-BP-induced damage of respiratory epithelial cells was related to the mitochondrial function pathway and further verified that 1-BP caused mitochondrial damage of respiratory epithelial cells, which was manifested as ultrastructural damage, decreased membrane potential, ATP, and MFN2 levels. These damages were associated with cellular oxidative stress responses. Pretreating cells with the agonists of PGC-1α and PPARα, we revealed that 1-BP affected the expression of PGC-1α and interfered with its coactivator PPARα levels, causing an increase in the expression of lipid-producing genes and a decrease in the expression of lipid-decomposing genes, thus leading to a lipid accumulation in respiratory epithelial cells. Meanwhile, the imbalance of lipid metabolism in respiratory epithelial cells induced by 1-BP further caused mitochondrial damage, and the effect was bidirectional. These findings suggested that 1-BP has a potential role in inducing respiratory epithelial cell damage and is associated with the PGC-1α/PPARα signaling pathway.

Berberine attenuates neuronal ferroptosis via the AMPK-NRF2-HO-1-signaling pathway in spinal cord-injured rats

Ferroptosis, characterized by iron-dependent accumulation of lipid peroxides, plays an important role in spinal cord injury (SCI). Berberine (BBR), as a lipid peroxide scavenger, has been widely used in treating other diseases; however, its role in ferroptosis has not been fully elucidated. Therefore, here, to test our hypothesis that BBR can reduce the severity of SCI and promote motor function recovery by inhibiting neuronal ferroptosis, we evaluated the changes in ferroptosis-related indicators after BBR administration by establishing a cellular ferroptosis model and an SCI contusion model. We found that BBR administration significantly reduces lipid peroxidation damage, maintains normal mitochondrial function, reduces excessive accumulation of iron ions, enhances antioxidant capacity, and activates the ferroptosis defense system in vivo and in vitro. Mechanistically, BBR alleviates neuronal ferroptosis by inducing adenosine monophosphate-activated protein kinase (AMPK) phosphorylation and up-regulating nuclear factor erythroid 2-related factor 2 (NRF2) and heme oxygenase-1 (HO-1) protein expression to promote glutathione production. BBR administration also significantly improves motor function recovery in SCI rats. Meanwhile, applying the AMPK inhibitor Compound C blocks the neuroprotective and all other effects of BBR. Collectively, our findings demonstrate that BBR can attenuate neuronal ferroptosis after SCI by activating the AMPK-NRF2-HO-1 pathway.

M6A RNA Methylation-Mediated TUG1 Stability Maintains Mitochondrial Homeostasis during Kidney Aging by Epigenetically Regulating PGC1-α Expression

Background: Aging is a significant risk factor for the increased incidence of acute kidney injury and chronic kidney disease, posing significant challenges to global public health. The role of N6-methyladenosine (m6A) in the development of chronic kidney disease has been reported, but the regulatory mechanism of m6A in kidney aging remains unclear. Results: In this study, we identified a long noncoding RNA (lncRNA), called taurine up-regulated 1 (TUG1), which exhibited a significantly decreased level of m6A modification in human aged kidney through the m6A-lncRNA epitranscriptome microarray. Bioinformatics analysis and machine learning predicted that TUG1 had potentially strong interaction with PGC1-α. RNA immunoprecipitation and chromatin immunoprecipitation analysis showed that TUG1 promoted proliferator-activated receptor γ coactivator-1α (PGC1-α) expression by directly interacting with its TUG-1 binding element region, thereby impacting mitochondrial quality control (MQC), cellular senescence, and renal fibrosis. Silencing the RNA m6A methylase methyltransferase 14 (METTL14) or the reader protein insulin-like growth factor 2 mRNA-binding proteins (IGF2BP2) resulted in the weakened stability of lncRNA TUG1, contributing to an imbalance in MQC. Conclusion: Our study demonstrated that the m6A modification and stability of TUG1 were mediated by METTL14 in an IGF2BP2-dependent manner, and modulate the mitochondrial homeostasis in kidney aging by direct targeting PGC-1α. These findings provide a new perspective on potential therapeutic targets for kidney aging. Antioxid. Redox Signal. 41, 993-1013.

Telomerase reverse transcriptase protects against diabetic kidney disease by promoting AMPK/PGC-1a-regulated mitochondrial energy homeostasis

Disordered glucose and lipid metabolism, coupled with disturbed mitochondrial bioenergetics, are pivotal in the initiation and development of diabetic kidney disease (DKD). While the essential role of telomerase reverse transcriptase (TERT) in regulating mitochondrial function in the cardiovascular system has been recognized, its specific function in maintaining mitochondrial homeostasis in DKD remains unclear. This study aimed to explore how TERT regulates mitochondrial function and the underlying mechanisms. In vitro, human renal proximal tubular HK-2 cells exposed to high glucose/high fat (HG/HF) presented significant downregulation of TERT and AMPK dephosphorylation. This led to decreased ATP production, altered NAD+/NADH ratios, reduced mitochondrial complex activities, increased mitochondrial dysfunction, lipid accumulation, and reactive oxygen species (ROS) production. Knockdown of TERT (si-TERT) further exacerbated mitochondrial dysfunction, decreased mitochondrial membrane potential, and lowered levels of cellular oxidative phosphorylation and glycolysis, as determined via a Seahorse X24 flux analyzer. Conversely, mitochondrial dysfunction was significantly alleviated after pcDNA-TERT plasmid transfection and adeno-associated virus (AAV) 9-TERT gene therapy in vivo. Notably, treatment with an AMPK inhibitor, activator, and si-PGC-1a (peroxisome proliferator-activated receptor γ coactivator-1α), resulted in mitochondrial dysfunction and decreased expression of genes related to energy metabolism and mitochondrial biogenesis. Our findings reveal that TERT protects mitochondrial function and homeostasis by partially activating the AMPK/PGC-1a signaling pathway. These results establish a crucial foundation for understanding TERT's critical role inmitochondrial regulation and its protective effect on DKD.

Metabolic reprogramming and renal fibrosis: what role might Chinese medicine play?

Metabolic reprogramming is a pivotal biological process in which cellular metabolic patterns change to meet the energy demands of increased cell growth and proliferation. In this review, we explore metabolic reprogramming and its impact on fibrotic diseases, providing a detailed overview of the key processes involved in the metabolic reprogramming of renal fibrosis, including fatty acid decomposition and synthesis, glycolysis, and amino acid catabolism. In addition, we report that Chinese medicine ameliorates renal inflammation, oxidative stress, and apoptosis in chronic kidney disease by regulating metabolic processes, thereby inhibiting renal fibrosis. Furthermore, we reveal that multiple targets and signaling pathways contribute to the metabolic regulatory effects of Chinese medicine. In summary, this review aims to elucidate the mechanisms by which Chinese medicine inhibits renal fibrosis through the remodeling of renal cell metabolic processes, with the goal of discovering new therapeutic drugs for treating renal fibrosis.

Early Diagnosis and Treatment of Kidney Injury: A Focus on Urine Protein

The kidney, an essential excretory organ of the body, performs a series of crucial physiological functions such as waste removal, maintenance of electrolyte and acid-base balance, and endocrine regulation. Due to its rich blood flow and high metabolic activity, the kidney is susceptible to damage. Currently, kidney injury is classified into acute kidney injury (AKI) and chronic kidney disease (CKD), both of which are associated with high rates of morbidity and mortality on a global scale. The current clinical diagnosis of renal injury relies on the assessment of renal filtration function using creatinine and urea nitrogen as "gold-standard" markers. However, the delayed response time, limited specificity, and reduced accuracy of creatinine and urea nitrogen in evaluating kidney injury have significantly hindered advancements in diagnostic methods for kidney injury. Urinary protein is widely utilized as a biomarker for the early diagnosis of kidney injury due to the selectivity of the glomerular filtration system determining whether proteins can pass through the filtration barrier based on their size and charge. Therefore, as a complex biological sample with varying charges and particle sizes, urinary protein is considered an ideal indicator for monitoring the progression of kidney disease. Exploring the relationship between urinary protein and the advancement of kidney injury based on differences in particle size and charge offers a new perspective for assessing and treating such injuries. Hence, we conducted a comprehensive review of 74 relevant studies to gain a thorough understanding of the physiological mechanism and significance of proteinuria production. The aim was to explore the challenges and opportunities in clinical urine protein detection, as well as to discuss strategies targeting glomerular filtration barriers in order to effectively reduce urine protein levels and treat kidney injury, which could provide a new perspective for identifying the progression of kidney injury.

RIPK3 causes mitochondrial dysfunction and albuminuria in diabetic podocytopathy through PGAM5-Drp1 signaling

BACKGROUND

Receptor-interacting protein kinase (RIPK)3 is an essential molecule for necroptosis and its role in kidney fibrosis has been investigated using various kidney injury models. However, the relevance and the underlying mechanisms of RIPK3 to podocyte injury in albuminuric diabetic kidney disease (DKD) remain unclear. Here, we investigated the role of RIPK3 in glomerular injury of DKD.

METHODS

We analyzed RIPK3 expression levels in the kidneys of patients with biopsy-proven DKD and animal models of DKD. Additionally, to confirm the clinical significance of circulating RIPK3, RIPK3 was measured by ELISA in plasma obtained from a prospective observational cohort of patients with type 2 diabetes, and estimated glomerular filtration rate (eGFR) and urine albumin-to-creatinine ratio (UACR), which are indicators of renal function, were followed up during the observation period. To investigate the role of RIPK3 in glomerular damage in DKD, we induced a DKD model using a high-fat diet in Ripk3 knockout and wild-type mice. To assess whether mitochondrial dysfunction and albuminuria in DKD take a Ripk3-dependent pathway, we used single-cell RNA sequencing of kidney cortex and immortalized podocytes treated with high glucose or overexpressing RIPK3.

RESULTS

RIPK3 expression was increased in podocytes of diabetic glomeruli with increased albuminuria and decreased podocyte numbers. Plasma RIPK3 levels were significantly elevated in albuminuric diabetic patients than in non-diabetic controls (p = 0.002) and non-albuminuric diabetic patients (p = 0.046). The participants in the highest tertile of plasma RIPK3 had a higher incidence of renal progression (hazard ratio [HR] 2.29 [1.05-4.98]) and incident chronic kidney disease (HR 4.08 [1.10-15.13]). Ripk3 knockout improved albuminuria, podocyte loss, and renal ultrastructure in DKD mice. Increased mitochondrial fragmentation, upregulated mitochondrial fission-related proteins such as phosphoglycerate mutase family member 5 (PGAM5) and dynamin-related protein 1 (Drp1), and mitochondrial ROS were decreased in podocytes of Ripk3 knockout DKD mice. In cultured podocytes, RIPK3 inhibition attenuated mitochondrial fission and mitochondrial dysfunction by decreasing p-mixed lineage kinase domain-like protein (MLKL), PGAM5, and p-Drp1 S616 and mitochondrial translocation of Drp1.

CONCLUSIONS

The study demonstrates that RIPK3 reflects deterioration of renal function of DKD. In addition, RIPK3 induces diabetic podocytopathy by regulating mitochondrial fission via PGAM5-Drp1 signaling through MLKL. Inhibition of RIPK3 might be a promising therapeutic option for treating DKD.

Gui Qi Zhuang Jin Decoction ameliorates mitochondrial dysfunction in sarcopenia mice via AMPK/PGC-1α/Nrf2 axis revealed by a metabolomics approach

OBJECTIVE

Sarcopenia, as a condition of muscle mass loss and functional decline typically diagnosed in elderly individuals, severely affects human physical activity, metabolic homeostasis, and quality of life. Gui Qi Zhuang Jin Decoction (GQZJD), an approved hospital-based prescription with years of clinical application, has been demonstrated to have a notable therapeutic effect on sarcopenia. However, its potential mechanism of action in the treatment of sarcopenia remains uncertain.

METHODS

Ultra-performance liquid chromatography paired with Q Exactive™ HF-X mass spectrometry (UPLC-QE-MS) was used to identify the ingredients of GQZJD. Subsequently, GQZJD observed the basic growth and muscles of the sarcopenia mouse, while the behavioral indicators were also tested. Muscle histopathology and serum oxidative stress biochemicals were also detected, and mitochondrial function and energy metabolism-related indicators in the gastrocnemius muscle were examined. Then, a metabolomics strategy was applied to predict possible pathways involving mitochondria by which GQZJD could improve sarcopenia. Finally, quantitative real-time polymerase chain reaction and western blot analyses were carried out to validate the effects of GQZJD on sarcopenia-induced mitochondrial dysfunction, together with uncovering the associated mechanisms.

RESULTS

Twenty-seven ingredients absorbed into the blood (IAIBs) of GQZJD were identified using UPLC-QE-MS, which were regarded as the main active ingredients behind its sarcopenia treatment effects. GQZJD administration increased the body weight, gastrocnemius muscle mass, and autonomic activity, mitigated muscle tissue morphology and pathology; and alleviated the oxidative stress levels in sarcopenia mice. Treatment with GQZJD also decreased the mitochondrial reactive oxygen species level and serum lipid peroxide Malonaldehyde concentration. and increased the mitochondrial membrane potential, adenosine triphosphate level, 8‑hydroxy-2-deoxyguanosine content, mitochondrial DNA copy number, and the mitochondrial fission factor dynamin-related protein 1. Non-targeted metabolomics suggested that the sarcopenia therapeutic effect of GQZJD on sarcopenia may occur through the glycerophospholipid metabolism, choline metabolism in cancer, phenylalanine metabolism and tyrosine metabolism pathways, implying an association with AMP-activated protein kinase (AMPK) and related signals. Further, the molecular docking results hinted that AMPK performed well in terms of binding energy with the 27 IAIBs of GQZJD (average binding energy, -7.5 kcal/mol). Finally, we determined that GQZJD significantly activated the key targets of the AMPK/peroxisome proliferator-activated receptor γ coactivator-1α (PGC-1α)/nuclear factor erythroid 2-related factor 2 (Nrf2) axis..

CONCLUSIONS

Our results demonstrated that GQZJD ameliorated d-galactose-induced sarcopenia by promoting the animal behaviours, facilitating mitochondrial function and restoring mitochondrial energy metabolism. with its effects mediated by the AMPK/PGC-1α/Nrf2 axis. Over all, GQZJD represents a promising therapeutic candidate that ameliorated sarcopenia in aging mice.

Novel Insights into Diabetic Kidney Disease

Diabetic kidney disease (DKD) is a major complication of diabetes mellitus (DM), affecting over one-third of type 1 and nearly half of type 2 diabetes patients. As the leading cause of end-stage renal disease (ESRD) globally, DKD develops through a complex interplay of chronic hyperglycemia, oxidative stress, and inflammation. Early detection is crucial, with diagnosis based on persistent albuminuria and reduced estimated glomerular filtration rate (eGFR). Treatment strategies emphasize comprehensive management, including glycemic control, blood pressure regulation, and the use of nephroprotective agents such as angiotensin-converting enzyme (ACE) inhibitors, angiotensin II receptor blockers (ARBs), sodium-glucose cotransporter-2 (SGLT2) inhibitors, and glucagon-like peptide-1 (GLP-1) receptor agonists. Ongoing research explores novel therapies targeting molecular pathways and non-coding RNAs. Preventive measures focus on rigorous control of hyperglycemia and hypertension, aiming to mitigate disease progression. Despite therapeutic advances, DKD remains a leading cause of ESRD, highlighting the need for continued research to identify new biomarkers and innovative treatments.

Morroniside attenuates podocytes lipid deposition in diabetic nephropathy: A network pharmacology, molecular docking and experimental validation study

BACKGROUND

Dysregulation of lipid metabolism is a key factor influencing the progression of diabetic nephropathy (DN). Morroniside (MOR) is a major active compound isolated from the traditional Chinese herb Cornus officinalis, our previous research found that it can improve the lipid deposition of renal tubular epithelial cells. The purpose of this study is to explore whether MOR can improve podocyte lipid deposition and its mechanism of reducing DN.

METHODS

Initially, we used network pharmacology and bioinformatics techniques to predict the relationship between renal lipid metabolism of MOR and DN. Subsequently, the binding activity of MOR with lipid-related proteins was studied by molecular docking to determine how MOR acts through these proteins. After determining the target of MOR, animal experiments and cell tests were carried out to verify it.

RESULTS

Using network pharmacology, bioinformatics, and molecular docking, target proteins for MOR treatment of DN were predicted and screened, including PGC-1α, LXRs, ABCA1, PPARY, CD36, and nephrin. It is particularly noted that MOR effectively binds to PGC-1α, while LXRs, ABCA1, PPARY and CD36 are downstream molecules of PGC-1α. Silencing the PGC-1α gene significantly reduced the therapeutic effects of MOR. Conversely, in groups without PGC-1α knockdown, MOR was able to increase the expression levels of PGC-1α and influence the expression of downstream proteins. Furthermore, through in vivo and in vitro experiments, utilizing techniques such as lipid droplet staining, PAS, MASSON staining, immunofluorescence, and Western blot, we found that MOR effectively elevated the expression levels of the podocyte protein nephrin and lipid metabolism-regulating proteins PGC-1α, PPARY, and ABCA1, while significantly inhibiting the expression of the lipid accumulation promoter CD36.

CONCLUSION

MOR can regulate the cholesterol efflux in podocytes via the PGC-1α/LXRs/ABCA1 signaling pathway, and control cholesterol intake via the PGC-1α/PPARY/CD36 signaling pathway, thereby ameliorating lipid deposition in DN.

Mechanisms of hepatic and renal injury in lipid metabolism disorders in metabolic syndrome

Metabolic syndrome (MetS) is a group of metabolic abnormalities that identifies people at risk for diabetes and cardiovascular disease. MetS is characterized by lipid disorders, and non-alcoholic fatty liver disease (NAFLD) and diabetic kidney disease (DKD) are thought to be the common hepatic and renal manifestations of MetS following abnormal lipid metabolism. This paper reviews the molecular mechanisms of lipid deposition in NAFLD and DKD, highlighting the commonalities and differences in lipid metabolic pathways in NAFLD and DKD. Hepatic and renal steatosis is the result of lipid acquisition exceeding lipid processing, i.e., fatty acid uptake and lipid regeneration exceed fatty acid oxidation and export. This process is directly regulated by the interactions of nuclear receptors, transporter proteins and transcription factors, whereas pathways such as oxidative stress, autophagy, cellular pyroptosis and gut flora are also key regulatory hubs for lipid metabolic homeostasis but act slightly differently in the liver and kidney. Such insights based on liver-kidney similarities and differences offer potential options for improved treatment.

Research hotspots and future trends in lipid metabolism in chronic kidney disease: a bibliometric and visualization analysis from 2004 to 2023

Background

Disorders of lipid metabolism play a key role in the initiation and progression of chronic kidney disease (CKD). Recently, research on lipid metabolism in CKD has rapidly increased worldwide. However, comprehensive bibliometric analyses in this field are lacking. Therefore, this study aimed to evaluate publications in the field of lipid metabolism in CKD over the past 20 years based on bibliometric analysis methods to understand the important achievements, popular research topics, and emerging thematic trends.

Methods

Literature on lipid metabolism in CKD, published between 2004 and 2023, was retrieved from the Web of Science Core Collection. The VOSviewer (v.1.6.19), CiteSpace (v.6.3 R1), R language (v.4.3.2), and Bibliometrix (v.4.1.4) packages (https://www.bibliometrix.org) were used for the bibliometric analysis and visualization. Annual output, author, country, institution, journal, cited literature, co-cited literature, and keywords were also included. The citation frequency and H-index were used to evaluate quality and influence.

Results

In total, 1,285 publications in the field of lipid metabolism in CKD were identified in this study. A total of 7,615 authors from 1,885 institutions in 69 countries and regions published articles in 466 journals. Among them, China was the most productive (368 articles), and the United States had the most citations (17,880 times) and the highest H-index (75). Vaziri Nosratola D, Levi Moshe, Fornoni Alessia, Zhao Yingyong, and Merscher Sandra emerged as core authors. Levi Moshe (2,247 times) and Vaziri Nosratola D (1,969 times) were also authors of the top two most cited publications. The International Journal of Molecular Sciences and Kidney International are the most published and cited journals in this field, respectively. Cardiovascular disease (CVD) and diabetic kidney disease (DKD) have attracted significant attention in the field of lipid metabolism. Oxidative stress, inflammation, insulin resistance, autophagy, and cell death are the key research topics in this field.

Conclusion

Through bibliometric analysis, the current status and global trends in lipid metabolism in CKD were demonstrated. CVD and DKD are closely associated with the lipid metabolism of patients with CKD. Future studies should focus on effective CKD treatments using lipid-lowering targets.

Ginsenoside Rh4 prevents endothelial dysfunction as a novel AMPK activator

BACKGROUND AND PURPOSE

The AMP-activated protein kinase (AMPK) signalling pathway is a desirable target for various cardiovascular diseases (CVD), while the involvement of AMPK-mediated specific downstream pathways and effective interventions in hyperlipidaemia-induced endothelial dysfunction remain largely unknown. Herein, we aim to identify an effective AMPK activator and to explore its efficacy and mechanism against endothelial dysfunction.

EXPERIMENTAL APPROACH

Molecular docking technique was adopted to screen for the potent AMPK activator among 11 most common rare ginsenosides. In vivo, poloxamer 407 (P407) was used to induce acute hyperlipidaemia in C57BL/6J mice. In vitro, palmitic acid (PA) was used to induce lipid toxicity in HAEC cells.

KEY RESULTS

We discovered the strongest binding of ginsenoside Rh4 to AMPKα1 and confirmed the action of Rh4 on AMPK activation. Rh4 effectively attenuated hyperlipidaemia-related endothelial injury and oxidative stress both in vivo and in vitro and restored cell viability, mitochondrial membrane potential and mitochondrial oxygen consumption rate in HAEC cells. Mechanistically, Rh4 bound to AMPKα1 and simultaneously up-regulated AKT/eNOS-mediated NO release, promoted PGC-1α-mediated mitochondrial biogenesis and inhibited P38 MAPK/NFκB-mediated inflammatory responses in both P407-treated mice and PA-treated HAEC cells. The AMPK inhibitor Compound C treatment completely abrogated the regulation of Rh4 on the above pathways and weakened the lowering effect of Rh4 on endothelial impairment markers, suggesting that the beneficial effects of Rh4 are AMPK dependent.

CONCLUSION AND IMPLICATIONS

Rh4 may serve as a novel AMPK activator to protect against hyperlipidaemia-induced endothelial dysfunction, providing new insights into the prevention and treatment of endothelial injury-associated CVD.

PGC-1α/LDHA signaling facilitates glycolysis initiation to regulate mechanically induced bone remodeling under inflammatory microenvironment

The mechanosensitivity of inflammation can alter cellular mechanotransduction. However, the underlying mechanism remains unclear. This study aims to investigate the metabolic mechanism of inflammation under mechanical force to guide tissue remodeling better. Herein, we found that inflammation hindered bone remodeling under mechanical force, accompanied by a simultaneous enhancement of oxidative phosphorylation (OXPHOS) and glycolysis. The control of metabolism direction through GNE-140 and Visomitin revealed that enhanced glycolysis might act as a compensatory mechanism to resist OXPHOS-induced osteoclastogenesis by promoting osteogenesis. The inhibited osteogenesis induced by inflammatory mechanical stimuli was concomitant with a reduced expression of peroxisome proliferator-activated receptor gamma coactivator 1-alpha (PGC-1α). PGC-1α knockdown impeded osteogenesis under mechanical force and facilitated osteoclastogenesis by enhancing OXPHOS. Conversely, PGC-1α overexpression attenuated the impairment of bone remodeling by inflammatory mechanical signals through promoting glycolysis. This process benefited from the PGC-1α regulation on the transcriptional and translational activity of lactate dehydrogenase A (LDHA) and the tight control of the extracellular acidic environment. Additionally, the increased binding between PGC-1α and LDHA proteins might contribute to the glycolysis promotion within the inflammatory mechanical environment. Notably, LDHA suppression effectively eliminated the bone repair effect mediated by PGC-1α overexpression within inflammatory mechanical environments. In conclusion, this study demonstrated a novel molecular mechanism illustrating how inflammation orchestrated glucose metabolism through glycolysis and OXPHOS to affect mechanically induced bone remodeling.

Prepubertal Repeated Berberine Supplementation Enhances Cerebrocerebellar Functions by Modulating Neurochemical and Behavioural Changes in Wistar Rats

Antioxidant-rich supplementation plays an essential role in the function of mammals' central nervous system. However, no research has documented the effect of berberine (BER) supplementation on the cerebrocerebellar function of prepubertal rats. The present study was designed to investigate the impact of BER supplementation on neurochemical and behavioural changes in prepubertal male rats. Five groups (90 ± 5 g, n = 7 each) of experimental rats were orally treated with corn oil or different doses of BER (25, 50, 100, and 200 mg/kg bw) from the 28th at 68 post-natal days. On the 69 days of life, animals underwent behavioural assessment in the open field, hanging wire, and negative geotaxis tests. The result revealed that BER administration improved locomotive and motor behaviour by increasing distance travelled, line crossings, average speed, time mobile, and absolute turn angle in open field test and decrease in time to re-orient on an incline plane, a decrease in immobility time relative to the untreated control. Furthermore, BER supplementation increased (p < 0.05) antioxidant enzyme activities such as SOD, CAT, GPx, GSH, and TSH and prevented increases (p < 0.05) in oxidative and inflammatory levels as indicated by decreases in RONS, LPO, XO, carbonyl protein, NO, MPO, and TNF-α compared to the untreated control. BER-treated animals a lessened number of dark-stained Nissl cells compared to the untreated control rats. Our findings revealed that BER minimised neuronal degeneration and lesions, improved animal behaviour, and suppressed oxidative and inflammatory mediators, which may probably occur through its agonistic effect on PPAR-α, PPAR-δ, and PPAR-γ - essential proteins known to resolve inflammation and modulate redox signalling towards antioxidant function.

Lipid homeostasis in diabetic kidney disease

Lipid homeostasis is crucial for proper cellular and systemic functions. A growing number of studies confirm the importance of lipid homeostasis in diabetic kidney disease (DKD). Lipotoxicity caused by imbalance in renal lipid homeostasis can further exasperate renal injury. Large lipid deposits and lipid droplet accumulation are present in the kidneys of DKD patients. Autophagy plays a critical role in DKD lipid homeostasis and is involved in the regulation of lipid content. Inhibition or reduction of autophagy can lead to lipid accumulation, which in turn further affects autophagy. Lipophagy selectively recognizes and degrades lipids and helps to regulate cellular lipid metabolism and maintain intracellular lipid homeostasis. Therefore, we provide a systematic review of fatty acid, cholesterol, and sphingolipid metabolism, and discuss the responses of different renal intrinsic cells to imbalances in lipid homeostasis. Finally, we discuss the mechanism by which autophagy, especially lipophagy, maintains lipid homeostasis to support the development of new DKD drugs targeting lipid homeostasis.

YiQi GuBen capsule alleviates OVA-induced asthma through improving mitochondrial dysfunction

Objective: This study aims to explore the effect of YiQi GuBen capsule on improving mitochondrial dysfunction in an animal model of asthma.Methods: The mice (n = 8) were divided into four groups including control (NC), ovalbumin (OVA), dexamethasone (OVA + DEX), and YiQi GuBen (OVA + YQGB) groups. Firstly, we established an OVA-induced mouse asthma model except for the NC group, which then were treated with dexamethasone and YiQi GuBen capsule. Subsequently, HE staining and Masson staining were used for pathological analysis of mice lung tissues. Next, we used transmission electron microscopy (TEM) to observe the effect of the Yiqi Guben capsule on the ultrastructure of mitochondria. Flow cytometry was used to analyze the ROS level, membrane potential, and the number of mitochondria in lung tissue. Moreover, we analyzed the copy number of mitochondrial DNA (mtDNA) and the expression levels of activator peroxisome proliferator-activated receptor γ coactivator-1α (PGC-1α) and mitochondrial transcription factor A (TFAM).Results: The results of the pathological analysis showed that after treatment with the YiQi GuBen capsule, the lung tissue damage was significantly reduced. In addition, we observed that the ultrastructural damage of mitochondria was improved. Flow cytometry proved that after treatment with the YiQi GuBen capsule, the level of ROS in the mitochondria was effectively reduced, while the mitochondrial membrane potential decreased and the number increased significantly. Moreover, we found that the copy number of mtDNA was significantly increased and the expression levels of PGC-1α and TFAM were significantly upgraded.Conclusion: This study suggests YiQi GuBen capsule can effectively improve mitochondrial dysfunction in the OVA-induced mouse model.

Mitochondrial metabolic reprogramming in diabetic kidney disease

Diabetic kidney disease, known as a glomerular disease, arises from a metabolic disorder impairing renal cell function. Mitochondria, crucial organelles, play a key role in substance metabolism via oxidative phosphorylation to generate ATP. Cells undergo metabolic reprogramming as a compensatory mechanism to fulfill energy needs for survival and growth, attracting scholarly attention in recent years. Studies indicate that mitochondrial metabolic reprogramming significantly influences the pathophysiological progression of DKD. Alterations in kidney metabolism lead to abnormal expression of signaling molecules and activation of pathways, inducing oxidative stress-related cellular damage, inflammatory responses, apoptosis, and autophagy irregularities, culminating in renal fibrosis and insufficiency. This review delves into the impact of mitochondrial metabolic reprogramming on DKD pathogenesis, emphasizing the regulation of metabolic regulators and downstream signaling pathways. Therapeutic interventions targeting renal metabolic reprogramming can potentially delay DKD progression. The findings underscore the importance of focusing on metabolic reprogramming to develop safer and more effective therapeutic approaches.

Roles of Mitochondrial Dysfunction in Diabetic Kidney Disease: New Perspectives from Mechanism to Therapy

Diabetic kidney disease (DKD) is a common microvascular complication of diabetes and the main cause of end-stage renal disease around the world. Mitochondria are the main organelles responsible for producing energy in cells and are closely involved in maintaining normal organ function. Studies have found that a high-sugar environment can damage glomeruli and tubules and trigger mitochondrial dysfunction. Meanwhile, animal experiments have shown that DKD symptoms are alleviated when mitochondrial damage is targeted, suggesting that mitochondrial dysfunction is inextricably linked to the development of DKD. This article describes the mechanisms of mitochondrial dysfunction and the progression and onset of DKD. The relationship between DKD and mitochondrial dysfunction is discussed. At the same time, the progress of DKD treatment targeting mitochondrial dysfunction is summarized. We hope to provide new insights into the progress and treatment of DKD.

Mechanism and bioinformatics analysis of the effect of berberine-enhanced fluconazole against drug-resistant Candida albicans

Biofilms produced by Candida albicans present a challenge in treatment with antifungal drug. Enhancing the sensitivity to fluconazole (FLC) is a reasonable method for treating FLC-resistant species. Moreover, several lines of evidence have demonstrated that berberine (BBR) can have antimicrobial effects. The aim of this study was to clarify the underlying mechanism of these effects. We conducted a comparative study of the inhibition of FLC-resistant strain growth by FLC treatment alone, BBR treatment alone, and the synergistic effect of combined FLC and BBR treatment. Twenty-four isolated strains showed distinct biofilm formation capabilities. The antifungal effect of combined FLC and BBR treatment in terms of the growth and biofilm formation of Candida albicans species was determined via checkerboard, time-kill, and fluorescence microscopy assays. The synergistic effect of BBR and FLC downregulated the expression of the efflux pump genes CDR1 and MDR, the hyphal gene HWP1, and the adhesion gene ALS3; however, the gene expression of the transcriptional repressor TUP1 was upregulated following treatment with this drug combination. Furthermore, the addition of BBR led to a marked reduction in cell surface hydrophobicity. To identify resistance-related genes and virulence factors through genome-wide sequencing analysis, we investigated the inhibition of related resistance gene expression by the combination of BBR and FLC, as well as the associated signaling pathways and metabolic pathways. The KEGG metabolic map showed that the metabolic genes in this strain are mainly involved in amino acid and carbon metabolism. The metabolic pathway map showed that several ergosterol (ERG) genes were involved in the synthesis of cell membrane sterols, which may be related to drug resistance. In this study, BBR + FLC combination treatment upregulated the expression of the ERG1, ERG3, ERG4, ERG5, ERG24, and ERG25 genes and downregulated the expression of the ERG6 and ERG9 genes compared with fluconazole treatment alone (p < 0.05).

Berberine attenuates brain aging via stabilizing redox homeostasis and inflammation in an accelerated senescence model of Wistar rats

Aging is a multifaceted and progressive physiological change of the organism categorized by the accumulation of deteriorating processes, which ultimately compromise the biological functions. The objective of this study was to investigate the anti-aging potential of berberine (BBR) in D-galactose (D-Gal) induced aging in rat models. In this study, male Wistar rats were divided into four groups: The control group was given only vehicle, the BBR group was treated with berberine orally, the D-Gal group was treated with D-galactose subcutaneously and the BBR + D-Gal group was treated with D-galactose and berberine simultaneously. D-galactose exposure elevated the pro-oxidants such as malondialdehyde (MDA) level, protein carbonyl and advanced oxidation protein products (AOPP) in the brain. It decreased the anti-oxidants such as reduced glutathione (GSH) and ferric reducing antioxidant potential (FRAP) in the brain. D-galactose treatment also reduced the mitochondrial complexes (I, II, III and IV) activities and elevated the inflammatory markers such as interleukine-6 (IL-6), tumor necrosis factor- α (TNF-α) and C-reactive protein (CRP). The mRNA expressions of IL-6 and TNF-α in the brain were upregulated following D-galactose exposure. Berberine co-treatment in D-galactose induced aging rat model prevented the alteration of pro-oxidant and anti-oxidant in the brain. Berberine treatment restored the mitochondrial complex activities in the brain and also normalized the inflammatory markers. Based on these findings we conclude that berberine treatment has the potential to mitigate brain aging in rats via stabilizing the redox equilibrium and neuroinflammation.

Differences in Metabolite Profiles of Dihydroberberine and Micellar Berberine in Caco-2 Cells and Humans-A Pilot Study

We investigated the pharmacokinetic pathway of berberine and its metabolites in vitro, in Caco-2 cells, and in human participants following the administration of dihydroberberine (DHB) and micellar berberine (LipoMicel®, LMB) formulations. A pilot trial involving nine healthy volunteers was conducted over a 24 h period; blood samples were collected and subjected to Ultra High-Performance Liquid Chromatography-High Resolution Mass Spectrometry (UHPLC-HRMS) analyses to quantify the concentrations of berberine and its metabolites. Pharmacokinetic correlations indicated that berberrubine and thalifendine follow distinct metabolic pathways. Additionally, jatrorrhizine sulfate appeared to undergo metabolism differently compared to the other sulfated metabolites. Moreover, berberrubine glucuronide likely has a unique metabolic pathway distinct from other glucuronides. The human trial revealed significantly higher blood concentrations of berberine metabolites in participants of the DHB treatment group compared to the LMB treatment group-except for berberrubine glucuronide, which was only detected in the LMB treatment group. Similarly, results from in vitro investigations showed significant differences in berberine metabolite profiles between DHB and LMB. Dihydroberberine, dihydroxy-berberrubine/thalifendine and jatrorrhizine sulfate were detected in LMB-treated cells, but not in DHB-treated cells; thalifendine and jatrorrhizine-glucuronide were detected in DHB-treated cells only. While DHB treatment provided higher blood concentrations of berberine and most berberine metabolites, both in vitro (Caco-2 cells) and in vivo human studies showed that treatment with LMB resulted in a higher proportion of unmetabolized berberine compared to DHB. These findings suggest potential clinical implications that merit further investigation in future large-scale trials.

Lipid metabolism disorder in diabetic kidney disease

Diabetic kidney disease (DKD), a significant complication associated with diabetes mellitus, presents limited treatment options. The progression of DKD is marked by substantial lipid disturbances, including alterations in triglycerides, cholesterol, sphingolipids, phospholipids, lipid droplets, and bile acids (BAs). Altered lipid metabolism serves as a crucial pathogenic mechanism in DKD, potentially intertwined with cellular ferroptosis, lipophagy, lipid metabolism reprogramming, and immune modulation of gut microbiota (thus impacting the liver-kidney axis). The elucidation of these mechanisms opens new potential therapeutic pathways for DKD management. This research explores the link between lipid metabolism disruptions and DKD onset.

Berberine attenuates inflammation and oxidative stress and modulates lymphocyte E-NTPDase in acute hyperlipidemia

Hyperlipidemia is a common clinically encountered health condition worldwide that promotes the development and progression of cardiovascular diseases, including atherosclerosis. Berberine (BBR) is a natural product with acknowledged anti-inflammatory, antioxidant, and metabolic effects. This study evaluated the effect of BBR on lipid alterations, oxidative stress, and inflammatory response in rats with acute hyperlipidemia induced by poloxamer-407 (P-407). Rats were pretreated with BBR (25 and 50 mg/kg) for 14 days and acute hyperlipidemia was induced by a single dose of P-407 (500 mg/kg). BBR ameliorated hypercholesterolemia, hypertriglyceridemia, and plasma lipoproteins in P-407-adminsitered rats. Plasma lipoprotein lipase (LPL) activity was decreased, and hepatic 3-hydroxy-3-methylglutaryl CoA (HMG-CoA) reductase activity was enhanced in hyperlipidemic rats. The expression of low-density lipoprotein receptor (LDL-R) and ATP-binding cassette transporter 1 (ABCA1) was downregulated in hyperlipidemic rats. BBR enhanced LPL activity, upregulated LDL-R, and ABCA1, and suppressed HMG-CoA reductase in P-407-administered rats. Pretreatment with BBR ameliorated lipid peroxidation, nitric oxide (NO), pro-inflammatory mediators (interleukin [IL]-6, IL-1β, tumor necrosis factor [TNF]-α, interferon-γ, IL-4 and IL-18) and enhanced antioxidants. In addition, BBR suppressed lymphocyte ecto-nucleoside triphosphate diphosphohydrolase (E-NTPDase) and ecto-adenosine deaminase (E-ADA) as well as NO and TNF-α release by macrophages isolated from normal and hyperlipidemic rats. In silico investigations revealed the binding affinity of BBR toward LPL, HMG-CoA reductase, LDL-R, PSK9, ABCA1, and E-NTPDase. In conclusion, BBR effectively prevented acute hyperlipidemia and its associated inflammatory responses by modulating LPL, cholesterolgenesis, cytokine release, and lymphocyte E-NTPDase and E-ADA. Therefore, BBR is an effective and safe natural compound that might be employed as an adjuvant against hyperlipidemia and its associated inflammation.

Empowering mitochondrial metabolism: Exploring L-lactate supplementation as a promising therapeutic approach for metabolic syndrome

Mitochondrial dysfunction plays a critical role in the pathogenesis of metabolic syndrome (MetS), affecting various cell types and organs. In MetS animal models, mitochondria exhibit decreased quality control, characterized by abnormal morphological structure, impaired metabolic activity, reduced energy production, disrupted signaling cascades, and oxidative stress. The aberrant changes in mitochondrial function exacerbate the progression of metabolic syndrome, setting in motion a pernicious cycle. From this perspective, reversing mitochondrial dysfunction is likely to become a novel and powerful approach for treating MetS. Unfortunately, there are currently no effective drugs available in clinical practice to improve mitochondrial function. Recently, L-lactate has garnered significant attention as a valuable metabolite due to its ability to regulate mitochondrial metabolic processes and function. It is highly likely that treating MetS and its related complications can be achieved by correcting mitochondrial homeostasis disorders. In this review, we comprehensively discuss the complex relationship between mitochondrial function and MetS and the involvement of L-lactate in regulating mitochondrial metabolism and associated signaling pathways. Furthermore, it highlights recent findings on the involvement of L-lactate in common pathologies of MetS and explores its potential clinical application and further prospects, thus providing new insights into treatment possibilities for MetS.

Peroxisome proliferator-activated receptor gamma coactivator-1 (PGC-1) family in physiological and pathophysiological process and diseases

Peroxisome proliferator-activated receptor gamma coactivator-1 (PGC-1) family (PGC-1s), consisting of three members encompassing PGC-1α, PGC-1β, and PGC-1-related coactivator (PRC), was discovered more than a quarter-century ago. PGC-1s are essential coordinators of many vital cellular events, including mitochondrial functions, oxidative stress, endoplasmic reticulum homeostasis, and inflammation. Accumulating evidence has shown that PGC-1s are implicated in many diseases, such as cancers, cardiac diseases and cardiovascular diseases, neurological disorders, kidney diseases, motor system diseases, and metabolic disorders. Examining the upstream modulators and co-activated partners of PGC-1s and identifying critical biological events modulated by downstream effectors of PGC-1s contribute to the presentation of the elaborate network of PGC-1s. Furthermore, discussing the correlation between PGC-1s and diseases as well as summarizing the therapy targeting PGC-1s helps make individualized and precise intervention methods. In this review, we summarize basic knowledge regarding the PGC-1s family as well as the molecular regulatory network, discuss the physio-pathological roles of PGC-1s in human diseases, review the application of PGC-1s, including the diagnostic and prognostic value of PGC-1s and several therapies in pre-clinical studies, and suggest several directions for future investigations. This review presents the immense potential of targeting PGC-1s in the treatment of diseases and hopefully facilitates the promotion of PGC-1s as new therapeutic targets.

A new direction in Chinese herbal medicine ameliorates for type 2 diabetes mellitus: Focus on the potential of mitochondrial respiratory chain complexes

ETHNOPHARMACOLOGICAL RELEVANCE

Diabetes is a common chronic disease. Chinese herbal medicine (CHM) has a history of several thousand years in the treatment of diabetes, and active components with hypoglycemic effects extracted from various CHM, such as polysaccharides, flavonoids, terpenes, and steroidal saponins, have been widely used in the treatment of diabetes.

AIM OF THE STUDY

Research exploring the potential of various CHM compounds to regulate the mitochondrial respiratory chain complex to improve type 2 diabetes mellitus (T2DM).

MATERIALS AND METHODS

The literature data were primarily obtained from authoritative databases such as PubMed, CNKI, Wanfang, and others within the last decade. The main keywords used include "type 2 diabetes mellitus", "Chinese medicine", "Chinese herbal medicine", "mitochondrial respiratory chain complex", and "mitochondrial dysfunction".

RESULTS

Chinese herbal medicine primarily regulates the activity of mitochondrial respiratory chain complexes in various tissues such as liver, adipose tissue, skeletal muscle, pancreatic islets, and small intestine. It improves cellular energy metabolism through hypoglycemic, antioxidant, anti-inflammatory and lipid-modulating effects. Different components of CHM can regulate the same mitochondrial respiratory chain complexes, while the same components of a particular CHM can regulate different complex activities. The active components of CHM target different mitochondrial respiratory chain complexes, regulate their aberrant changes and effectively improve T2DM and its complications.

CONCLUSION

Chinese herbal medicine can modulate the function of mitochondrial respiratory chain complexes in various cell types and exert their hypoglycemic effects through various mechanisms. CHM has significant therapeutic potential in regulating mitochondrial respiratory chain complexes to improve T2DM, but further research is needed to explore the underlying mechanisms and conduct clinical trials to assess the safety and efficacy of these medications. This provides new perspectives and opportunities for personalized improvement and innovative developments in diabetes management.

Canagliflozin improves fatty acid oxidation and ferroptosis of renal tubular epithelial cells via FOXA1-CPT1A axis in diabetic kidney disease

Impaired fatty acid oxidation (FAO) is a metabolic hallmark of renal tubular epithelial cells (RTECs) under diabetic conditions. Disturbed FAO may promote cellular oxidative stress and insufficient energy production, leading to ferroptosis subsequently. Canagliflozin, an effective anti-hyperglycemic drug, may exert potential reno-protective effects by upregulating FAO and inhibiting ferroptosis in RTECs. However, the mechanisms involved remain unclear. The present study is aimed to characterize the detailed mechanisms underlying the impact of canagliflozin on FAO and ferroptosis. Type 2 diabetic db/db mice were administrated daily by gavage with canagliflozin (20 mg/kg/day, 40 mg/kg/day) or positive control drug pioglitazone (10 mg/kg/day) for 12 weeks. The results showed canagliflozin effectively improved renal function and structure, reduced lipid droplet accumulation, enhanced FAO with increased ATP contents and CPT1A expression, a rate-limiting enzyme of FAO, and relieved ferroptosis in diabetic mice. Moreover, overexpression of FOXA1, a transcription factor related with lipid metabolism, was observed to upregulate the level of CPT1A, and further alleviated ferroptosis in high glucose cultured HK-2 cells. Whereas FOXA1 knockdown had the opposite effect. Mechanistically, chromatin immunoprecipitation assay and dual-luciferase reporter gene assay results demonstrated that FOXA1 transcriptionally promoted the expression of CPT1A through a sis-inducible element located in the promoter region of the protein. In conclusion, these data suggest that canagliflozin improves FAO and attenuates ferroptosis of RTECs via FOXA1-CPT1A axis in diabetic kidney disease.

Isorhamnetin alleviates cisplatin-induced acute kidney injury via enhancing fatty acid oxidation

Cisplatin is an effective chemotherapy drug widely used in the treatment of various solid tumors. However, the clinical usage of cisplatin is limited by its nephrotoxicity. Isorhamnetin, a natural flavanol compound, displays remarkable pharmacological effects, including anti-inflammatory and anti-oxidation. In this study, we aimed to investigate the potential of isorhamnetin in alleviating acute kidney injury induced by cisplatin. In vitro study showed that isorhamnetin significantly suppressed the cytotoxic effects of cisplatin on human tubular epithelial cells. Furthermore, isorhamnetin exerted significantly inhibitory effects on cisplatin-induced apoptosis and inflammatory response. In acute kidney injury mice induced by a single intraperitoneal injection with 20 mg/kg cisplatin, oral administration of isorhamnetin two days before or 2 h after cisplatin injection effectively ameliorated renal function and renal tubule injury. Transcriptomics RNA-seq analysis of the mice kidney tissues suggested that isorhamnetin treatment may protect against cisplatin-induced nephrotoxicity via PGC-1α mediated fatty acid oxidation. Isorhamnetin achieved significant enhancements in the lipid clearance, ATP level, as well as the expression of PGC-1α and its downstream target genes PPARα and CPT1A, which were otherwise impaired by cisplatin. In addition, the protection effects of isorhamnetin against cisplatin-induced nephrotoxicity were abolished by a PGC-1α inhibitor, SR-18292. In conclusion, our findings indicate that isorhamnetin could protect against cisplatin-induced acute kidney injury by inducing PGC-1α-dependent reprogramming of fatty acid oxidation, which highlights the clinical potential of isorhamnetin as a therapeutic approach for the management of cisplatin-induced nephrotoxicity.

PGC1-α in diabetic kidney disease: unraveling renoprotection and molecular mechanisms

Mitochondrial dysfunction represents a pivotal aspect of the pathogenesis and progression of diabetic kidney disease (DKD). Central to the orchestration of mitochondrial biogenesis is the peroxisome proliferator-activated receptor γ coactivator 1-α (PGC1-α), a master regulator with a profound impact on mitochondrial function. In the context of DKD, PGC1-α exhibits significant downregulation within intrinsic renal cells, precipitating a cascade of deleterious events. This includes a reduction in mitochondrial biogenesis, heightened levels of mitochondrial oxidative stress, perturbed mitochondrial dynamics, and dysregulated mitophagy. Concurrently, structural and functional abnormalities within the mitochondrial network ensue. In stark contrast, the sustained expression of PGC1-α emerges as a beacon of hope in maintaining mitochondrial homeostasis within intrinsic renal cells, ultimately demonstrating an impressive renoprotective potential in animal models afflicted with DKD. This comprehensive review aims to delve into the recent advancements in our understanding of the renoprotective properties wielded by PGC1-α. Specifically, it elucidates the potential molecular mechanisms underlying PGC1-α's protective effects within renal tubular epithelial cells, podocytes, glomerular endothelial cells, and mesangial cells in the context of DKD. By shedding light on these intricate mechanisms, we aspire to provide valuable insights that may pave the way for innovative therapeutic interventions in the management of DKD.

Natural products as pharmacological modulators of mitochondrial dysfunctions for the treatment of diabetes and its complications: An update since 2010

Diabetes, characterized as a well-known chronic metabolic syndrome, with its associated complications pose a substantial and escalating health and healthcare challenge on a global scale. Current strategies addressing diabetes are mainly symptomatic and there are fewer available curative pharmaceuticals for diabetic complications. Thus, there is an urgent need to identify novel pharmacological targets and agents. The impaired mitochondria have been associated with the etiology of diabetes and its complications, and the intervention of mitochondrial dysfunction represents an attractive breakthrough point for the treatments of diabetes and its complications. Natural products (NPs), with multicenter characteristics, multi-pharmacological activities and lower toxicity, have been caught attentions as the modulators of mitochondrial functions in the therapeutical filed of diabetes and its complications. This review mainly summarizes the recent progresses on the potential of 39 NPs and 2 plant-extracted mixtures to improve mitochondrial dysfunction against diabetes and its complications. It is expected that this work may be useful to accelerate the development of innovative drugs originated from NPs and improve upcoming therapeutics in diabetes and its complications.

Mechanisms and efficacy of traditional Chinese herb monomers in diabetic kidney disease

Diabetic kidney disease (DKD) is a serious complication of diabetes and is the primary cause of end-stage renal disease. Current treatment strategies primarily focus on the inhibition of the renin-angiotensin-aldosterone system and the attainment of blood glucose control. Although current medical therapies for DKD have been shown to delay disease progression and improve long-term outcomes, their efficacy is limited and they may be restricted in certain cases, particularly when hyperkalemia is present. Traditional Chinese medicine (TCM) treatment has emerged as a significant complementary approach for DKD. TCM monomers, derived from various Chinese herbs, have been found to modulate multiple therapeutic targets and exhibit a broad range of therapeutic effects in patients with DKD. This review aims to summarize the mechanisms of action of TCM monomers in the treatment of DKD, based on findings from clinical trials, as well as cell and animal studies. The results of these investigations demonstrate the potential effective use of TCM monomers in treating or preventing DKD, offering a promising new direction for future research in the field. By providing a comprehensive overview of the mechanisms and efficacy of TCM monomers in DKD, this review highlights the potential of these natural compounds as alternative therapeutic options for improving outcomes in patients with DKD.

From Energy Metabolic Change to Precision Therapy: a Holistic View of Energy Metabolism in Heart Failure

Heart failure (HF) is a complex and multifactorial disease that affects millions of people worldwide. It is characterized by metabolic disturbances of substrates such as glucose, fatty acids (FAs), ketone bodies, and amino acids, which lead to changes in cardiac energy metabolism pathways. These metabolic alterations can directly or indirectly promote myocardial remodeling, thereby accelerating the progression of HF, resulting in a vicious cycle of worsening symptoms, and contributing to the increased hospitalization and mortality among patients with HF. In this review, we summarized the latest researches on energy metabolic profiling in HF and provided the related translational therapeutic strategies for this devastating disease. By taking a holistic approach to understanding energy metabolism changes in HF, we hope to provide comprehensive insights into the pathophysiology of this challenging condition and identify novel precise targets for the development of more effective treatments.

Exploring the molecular mechanism of berberine for treating diabetic nephropathy based on network pharmacology

BACKGROUND AND PURPOSE

Diabetic nephropathy (DN) is a prevalent complication of diabetes mellitus characterized by hyperglycemia, hyperlipidemia, albuminuria and edema. Increasing evidence indicated that berberine (BBR) could alleviate the occurrence and development of DN. However, the molecular mechanism underlying the beneficial effects of BBR in the treatment of DN remains unclear.

METHODS

The online public databases were chosen to screen the relevant targets of BBR and DN and the screened overlapped targets were analyzed by GO enrichment analysis, KEGG enrichment analysis and protein-protein interaction network analysis. The interaction between BBR and the key proteinwas verified by molecular docking and cellularthermalshiftassay. Additionally, the expression of key proteins and related indicators of DN were verified by immunofluorescence and western blot in vitro and in vivo.

RESULTS

We successfully identified 92 overlapped targets of BBR and DN based on network pharmacology. Notably, VEGFR2 was identified to be the main target of BBR. Meanwhile, we found that BBR exhibited a high binding affinity to VEGFR2 protein, as confirmed by molecular docking and CETSA. This binding led to interfering with the PI3K/AKT/mTOR signaling pathway. In addition, we found that BBR could inhibit the abnormal proliferation of mesangial cells and reduce the expression of downstream pathway protein in vitro and in vivo. Finally, BBR was found to effectively lower the level of blood glucose and improve kidney function in mice, highlighting its potential as a therapeutic agent for the treatment of DN.

CONCLUSION

Berberine interfered the PI3K/AKT/mTOR signaling pathway via targeting VEGFR2 protein, further led to the inhibition of abnormal proliferation of mesangial cells and ultimately resulted in improved renal function.

MiR-29b Alleviates High Glucose-induced Inflammation and Apoptosis in Podocytes by Down-regulating PRKAB2

BACKGROUND

Podocyte injury and inflammatory response are the core contributors to the pathogenesis of diabetic nephropathy. This study aims to identify novel regulatory miRNAs and elucidate their underlying mechanisms, which will help us understand the pathogenesis of diabetic nephropathy more comprehensively.

MATERIALS AND METHODS

Different glucose concentrations were used to treat podocytes to mimic the pathology of diabetic nephropathy in vitro. Flow cytometry was used to determine cell apoptosis. Inflammatory cytokines released by podocytes were measured by using an enzymelinked immunosorbent assay (ELISA). Western Blot was used to detect the expression of PRKAB2 protein in podocytes.

RESULTS

Genecard and g: profiler results revealed that miR-29b might be involved in regulating HG-induced cell injury. QRT-PCR indicated that HG-induced downregulation of miR-29b in podocytes. MiR-29b knockdown promoted cell apoptosis and inflammatory response in podocytes. MiR-29b overexpression repressed cell apoptosis and inflammatory response induced by high glucose treatment in podocytes. Luciferase reporter assay and Western Blot showed that miR-29b targeted PRKAB2 to negatively regulate PRKAB2 expression directly. Knockdown of PRKAB2 reversed the increased cell apoptosis and inflammation induced by miR-29b inhibitors.

CONCLUSION

MiR-29b plays a role in inhibiting inflammation and apoptosis in high glucose (HG) treated podocytes by negatively regulating PRKAB2 expression. This study provides new potential targets and ideas for the treatment of diabetic nephropathy.

Interplay of lipid metabolism and inflammation in podocyte injury

Podocytes are critical for maintaining permselectivity of the glomerular filtration barrier, and podocyte injury is a major cause of proteinuria in various primary and secondary glomerulopathies. Lipid dysmetabolism and inflammatory activation are the distinctive hallmarks of podocyte injury. Lipid accumulation and lipotoxicity trigger cytoskeletal rearrangement, insulin resistance, mitochondrial oxidative stress, and inflammation. Subsequently, inflammation promotes the progression of glomerulosclerosis and renal fibrosis via multiple pathways. These data suggest that lipid dysmetabolism positively or negatively regulates inflammation during podocyte injury. In this review, we summarize recent advances in the understanding of lipid metabolism and inflammation, and highlight the potential association between lipid metabolism and podocyte inflammation.