Xuesaitong Protects Podocytes from Apoptosis in Diabetic Rats through Modulating PTEN-PDK1-Akt-mTOR Pathway

The Ethyl Acetate Extract of Phyllanthus emblica L. Alleviates Diabetic Nephropathy in a Murine Model of Diabetes

Oil-Gan is the fruit of the genus Phyllanthus emblica L. The fruits have excellent effects on health care and development values. There are many methods for the management of diabetic nephropathy (DN). However, there is a lack of effective drugs for treating DN throughout the disease course. The primary aim of this study was to examine the protective effects (including analyses of urine and blood, and inflammatory cytokine levels) and mechanisms of the ethyl acetate extract of P. emblica (EPE) on db/db mice, an animal model of diabetic nephropathy; the secondary aim was to examine the expression levels of p- protein kinase Cα (PKCα)/t-PKCα in the kidney and its downregulation of vascular endothelial growth factor (VEGF) and fibrosis gene transforming growth factor-β1 (TGF-β1) by Western blot analyses. Eight db/m mice were used as the control group. Forty db/db mice were randomly divided into five groups. Treatments included a vehicle, EPE1, EPE2, EPE3 (at doses of 100, 200, or 400 mg/kg EPE), or the comparative drug aminoguanidine for 8 weeks. After 8 weeks of treatment, the administration of EPE to db/db mice effectively controlled hyperglycemia and hyperinsulinemia by markedly lowering blood glucose, insulin, and glycosylated HbA1c levels. The administration of EPE to db/db mice decreased the levels of BUN and creatinine both in blood and urine and reduced urinary albumin excretion and the albumin creatine ratio (UACR) in urine. Moreover, EPE treatment decreased the blood levels of inflammatory cytokines, including kidney injury molecule-1 (KIM-1), C-reactive protein (CRP), and NLR family pyrin domain containing 3 (NLRP3). Our findings showed that EPE not only had antihyperglycemic effects but also improved renal function in db/db mice. A histological examination of the kidney by immunohistochemistry indicated that EPE can improve kidney function by ameliorating glomerular morphological damage following glomerular injury; alleviating proteinuria by upregulating the expression of nephrin, a biomarker of early glomerular damage; and inhibiting glomerular expansion and tubular fibrosis. Moreover, the administration of EPE to db/db mice increased the expression levels of p- PKCα/t-PKCα but decreased the expression levels of VEGF and renal fibrosis biomarkers (TGF-β1, collagen IV, p-Smad2, p-Smad3, and Smad4), as shown by Western blot analyses. These results implied that EPE as a supplement has a protective effect against renal dysfunction through the amelioration of insulin resistance as well as the suppression of nephritis and fibrosis in a DN model.

Notoginsenoside Fc, a novel renoprotective agent, ameliorates glomerular endothelial cells pyroptosis and mitochondrial dysfunction in diabetic nephropathy through regulating HMGCS2 pathway

BACKGROUND

Diabetic nephropathy (DN) is the primary cause of end-stage renal disease (ESRD), and the therapeutic strategies for DN are limited. Notoginsenoside Fc (Fc), a novel saponin isolated from Panax Notoginseng (PNG), has been reported to alleviate vascular injury in diabetic rats. However, the protective effects of Fc on DN remain unclear.

PURPOSE

To investigate the beneficial effects and mechanisms of Fc on DN.

METHODS

Db/db mice were treated with 2.5, 5 and 10 mg·kg-1·d-1 of Fc for 8 weeks. High glucose (HG) induced mouse glomerular endothelial cells (GECs) were treated with 2.5, 5 and 10 μM of Fc for 24 h.

RESULTS

Our data found that Fc ameliorated urinary microalbumin level, kidney dysfunction and histopathological damage in diabetic mice. Moreover, Fc alleviated the accumulation of oxidative stress, the collapse of mitochondrial membrane potential and the expression of mitochondrial fission proteins, such as Drp-1 and Fis1, while increased the expression of mitochondrial fusion protein Mfn2. Fc also decreased pyroptosis-related proteins levels, such as TXNIP, NLRP3, cleaved caspase-1, and GSDMD-NT, indicating that Fc ameliorated GECs pyroptosis. In addition, 3-hydroxy-3-methylglutaryl-CoA synthase 2 (HMGCS2) expression was increased in diabetic group, which was partially abrogated by Fc. Our data further proved that knockdown of HMGCS2 could restrain HG-induced GECs mitochondrial dysfunction and pyroptosis. These results indicated that the inhibitory effects of Fc on mitochondrial damage and pyroptosis were associated with the suppression of HMGCS2.

CONCLUSION

Taken together, this study clearly demonstrated that Fc ameliorated GECs pyroptosis and mitochondrial dysfunction partly through regulating HMGCS2 pathway, which might provide a novel drug candidate for DN.

Acteoside protects podocyte against apoptosis through regulating AKT/GSK-3β signaling pathway in db/db mice

BACKGROUND

Podocyte apoptosis is one of the important pathological mechanisms of diabetic kidney disease (DKD). Acteoside (Act), a major active component of Rehmannia glutinosa leaves total glycoside, has a strong renoprotective action. Our study aims to demonstrate Act's renoprotective actions in db/db mice.

METHODS

We adopted C57BLKS/J db/db mice as DKD animal models. After 8 weeks of Act administration, the 24-hour urine albumin, renal function index, and blood lipid levels were quantified using matching kits. Renal pathology was evaluated by HE and PAS staining. The podocyte damage and apoptosis-related signaling pathway were observed by using immunohistochemistry, western blot, and TUNEL staining.

RESULTS

The albuminuria of db/db mice was reduced from 391 ug/24 h to 152 ug/24 h, and renal pathology changes were alleviated after Act administration. The western blot and immunohistochemistry showed that Act treatment upregulated the synaptopodin and podocin expression compared with db/db mice, while the TUNEL staining indicated podocyte apoptosis was inhibited. The B-cell lymphoma-2 (Bcl-2) level was upregulated in the Act group, but cleaved caspase-3 and Bcl-2 associated X protein (Bax) expression declined, while the protein kinase B/glycogen synthase kinase-3β (AKT/GSK-3β) signaling pathway was repressed.

CONCLUSIONS

By inhibiting the AKT/GSK-3β signaling pathway, Act protected podocytes from apoptosis, decreasing the urine albumin of db/db mice and delaying the course of DKD.

Pericyte Loss in Diseases

Pericytes are specialized cells located in close proximity to endothelial cells within the microvasculature. They play a crucial role in regulating blood flow, stabilizing vessel walls, and maintaining the integrity of the blood-brain barrier. The loss of pericytes has been associated with the development and progression of various diseases, such as diabetes, Alzheimer's disease, sepsis, stroke, and traumatic brain injury. This review examines the detection of pericyte loss in different diseases, explores the methods employed to assess pericyte coverage, and elucidates the potential mechanisms contributing to pericyte loss in these pathological conditions. Additionally, current therapeutic strategies targeting pericytes are discussed, along with potential future interventions aimed at preserving pericyte function and promoting disease mitigation.

Xuesaitong promotes myocardial angiogenesis in myocardial infarction mice by inhibiting MiR-3158-3p targeting Nur77

This study aims to investigate the regulatory effect of Xuesaitong (XST) and miR-3158-3p on angiogenesis. All mice were randomly assigned into Sham group, Model group, XST group, XST + miR-3158-3P-overexpression (miRNA-OE) group. XST was found to increase the left ventricular anterior wall thickness at end diastole and end systole (LVAWd and LVAWs), left ventricular internal dimension at end diastole and end systole (LVIDd and LVIDs), fractional shortening (FS), and ejection fraction (EF) and decrease the proportion of fibrotic areas in mice. In contrast to those in Sham group, the protein expressions of Nur77, p-PI3K, HIF-1α, VEGFs, COX-2 in the heart tissues of mice in Model group were elevated and further increased after XST treatment in comparison with those in Model group. Nur77-/- mice were utilized. It was found that XST enhanced cell viability through a methyl thiazolyl tetrazolium assay and facilitated angiogenesis in each group, as assessed by a catheter formation assay. Specifically, XST was shown to promote the formation of blood vessels. Moreover, the protein expression levels of Associated proteins in the heart tissues of Nur77-/- mice were dramatically reduced in mice in Model and XST group compared with those in WT mice. Additionally, the above-mentioned protein expressions in the heart tissues of Nur77-/- mice did not change significantly in mice in Model + miRNA-OE + XST group compared with those in WT mice, suggesting that miR-3158-3p can specifically inhibit the expression of Nur77. In conclusion, XST inhibits miR-3158-3p targeting Nur77 to facilitate myocardial angiogenesis in mice with myocardial infarction.

Notoginsenoside Fc ameliorates renal tubular injury and mitochondrial damage in acetaminophen-induced acute kidney injury partly by regulating SIRT3/SOD2 pathway

Introduction

Mitochondria dysfunction is one of the primary causes of tubular injury in acute kidney injury (AKI). Notoginsenoside Fc (Fc), a new saponin isolated from Panax notoginseng, exhibited numerous pharmacological actions. However, the beneficial effects of Fc on renal tubular impairment and mitochondrial dysfunction in AKI have not been fully studied.

Methods

In this study, we established acetaminophen (APAP)-induced AKI model in mice to examine the therapeutic impacts of Fc on AKI.

Results

Our results showed that Fc could decrease the levels of the serum creatinine (Scr), blood urea nitrogen (BUN) and Cystatin C in mice with AKI. Fc also ameliorated renal histopathology, renal tubular cells apoptosis and restored expression of apoptosis-related proteins such as Bax, Bcl-2 and caspase3 (C-caspase3). Additionally, Fc increased the protein expression of SIRT3 and SOD2 in kidneys from mice with AKI. In vitro studies further showed Fc reduced the apoptosis of HK-2 cells exposure to APAP, attenuated the loss of mitochondrial membrane potential and decreased the formation of mitochondrial superoxide. Fc also partly restored the protein expression of Bax, Bcl-2, C-Caspase3, SIRT3, and SOD2 in HK-2 cells exposure to APAP.

Conclusion

In summary, Fc might reduce renal tubular injury and mitochondrial dysfunction in AKI partly through the regulation of SIRT3/SOD2 pathway.

Exploring the Mechanism of Panax notoginseng Saponins against Alzheimer's Disease by Network Pharmacology and Experimental Validation

Background

Panax notoginseng saponins (PNS) have been used for neurodegenerative disorders such as cerebral ischemia and Alzheimer's disease (AD). Although increasing evidences show the neuron protective effects of PNS, the vital compounds and their functional targets remain elusive. To explore the potential functional ingredients of PNS for the AD treatment and their molecular mechanisms, an in vitro neuron injured model induced by Aβ was investigated, and the potential mechanism was predicted by network pharmacology approach and validated by molecular biology methods.

Methods

Network pharmacology approach was used to reveal the relationship between ingredient-target disease and function-pathway of PNS on the treatment of AD. The active ingredients of PNS were collected from TCMSP, PubChem database, and literature mining in PubMed database. DrugBank and GeneCards database were used to predict potential targets for AD. The STRING database was performed to reveal enrichment of these target proteins, protein-protein interactions, and related pathways. Networks were visualized by utilizing Cytoscape software. The enrichment analysis was performed by the DAVID database. Finally, neuroprotective effect and predictive mechanism of PNS were investigated in an in vitro AD model established by Aβ_25–35-treated PC12 cells.

Results

An ingredient-target disease and function-pathway network demonstrated that 38 active ingredients were derived from PNS modulated 364 common targets shared by PNS and AD. GO and KEGG analysis, further clustering analysis, showed that mTOR signaling targets were associated with the neuroprotective effects of PNS. In Aβ-treated PC12 cells, PNS treatment improved neuroprotective effect, including mTOR inhibition and autophagy activation.

Conclusions

Collectively, the protective effects of PNS on AD-neuron injury are related to the inhibition of mTOR and autophagy activation.

Panax notoginseng saponin attenuates the hypoxic-ischaemic injury in neonatal rats by regulating the expression of neurotrophin factors

Neonatal hypoxic-ischaemic (HI) injury is a serious complication of neonatal asphyxia and the leading cause of neonatal acute death and chronic neurological injury, and the effective therapeutic method is lacking to improve patients' outcomes. We reported in this study that panax notoginseng saponin (PNS) may provide a treatment option for HI. HI model was established using neonatal Sprague-Dawley rats and then intraperitoneally injected with different dosage of PNS, once a day for 7 days. Histological staining and behavioural evaluations were performed to elucidate the pathological changes and neurobehavioural variation after PNS treatment. We found PNS administration significantly reduced the infarct volume of brain tissues and improved the autonomous activities of neonatal rats, especially with higher dosage. PNS treatment at 40 mg/kg reduced neuronal damage, suppressed neuronal apoptosis and depressed astroglial reactive response. Moreover, the long-term cognitive and motor functions were also improved after PNS treatment at 40 mg/kg. Importantly, PNS treatment elevated the levels of BDNF and TrkB but decreased the expression of p75NTR both in the cortex and hippocampus of HI rats. The therapeutic efficacy of PNS might be correlated with PNS-activated BDNF/TrkB signalling and inactivation of p75NTR expression, providing a novel potential therapy for alleviating HI injury.

Protective Effects of Ethanolic Extract from Rhizome of Polygoni avicularis against Renal Fibrosis and Inflammation in a Diabetic Nephropathy Model

Progressive diabetic nephropathy (DN) in diabetes leads to major morbidity and mortality. The major pathological alterations of DN include mesangial expansion, extracellular matrix alterations, tubulointerstitial fibrosis, and glomerular sclerosis. Polygoni avicularis is widely used in traditional oriental medicine and has long been used as a diuretic, astringent, insecticide and antihypertensive. However, to the best of the authors' knowledge, the effects of the ethanolic extract from rhizome of Polygoni avicularis (ER-PA) on DN have not yet been assessed. The present study aimed to identify the effect of ER-PA on renal dysfunction, which has been implicated in DN in human renal mesangial cells and db/db mice and investigate its mechanism of action. The in vivo experiment was performed using Polygoni avicularis-ethanol soluble fraction (ER-PA) and was administrated to db/db mice at 10 and 50 mg/kg dose. For the in vitro experiments, the human renal mesangial cells were induced by high glucose (HG, 25 mM). The ER-PA group showed significant amelioration in oral glucose tolerance, and insulin resistance index. ER-PA significantly improved the albumin excretion and markedly reduced plasma creatinine, kidney injury molecule-1 and C-reactive protein. In addition, ER-PA significantly suppressed inflammatory cytokines. Histopathologically, ER-PA attenuated glomerular expansion and tubular fibrosis in db/db mice. Furthermore, ER-PA suppressed the expression of renal fibrosis biomarkers (TGF and Collagen IV). ER-PA also reduced the NLR family pyrin domain containing 3 inflammatory factor level. These results suggest that ER-PA has a protective effect against renal dysfunction through improved insulin resistance as well as the inhibition of nephritis and fibrosis in DN.

Therapeutic options of TCM for organ injuries associated with COVID-19 and the underlying mechanism

BACKGROUND

Coronavirus disease-2019 (COVID-19) caused by infection with severe acute respiratory coronavirus-2 (SARS-CoV-2) has been spreading rapidly throughout China and in other countries since the end of 2019. The World Health Organization (WHO) has declared that the epidemic is a public health emergency of international concerns. The timely and appropriate measures for treating COVID-19 in China, which are inseparable from the contribution of traditional Chinese medicine (TCM), have won much praise of the world.

PURPOSE

This review aimed to summarize and discuss the essential role of TCM in protecting tissues from injuries associated with COVID-19, and accordingly to clarify the possible action mechanisms of TCM from the perspectives of anti-inflammatory, antioxidant and anti-apoptotic effects.

METHODS

Electronic databases such as Pubmed, ResearchGate, Science Direct, Web of Science, medRixv and Wiley were used to search scientific literatures.

RESULTS

The present review found that traditional Chinese herbs commonly used for the clinical treatment of organ damages caused by COVID-19, such as Scutellaria baicalensis, Salvia miltiorrhizaSalvia miltiorrhiza, and ginseng, could act on multiple signaling pathways involved in inflammation, oxidative stress and apoptosis.

CONCLUSION

TCM could protect COVID-19 patients from tissue injuries, a protection that might be, at least partially, attributed to the anti-inflammatory, antioxidant and anti-apoptotic effects of the TCM under investigation. This review provides evidence and support for clinical treatment and novel drug research using TCM.

Research Progress on the Pathological Mechanisms of Podocytes in Diabetic Nephropathy

Diabetic nephropathy (DN) is not only an important microvascular complication of diabetes but also the main cause of end-stage renal disease. Studies have shown that the occurrence and development of DN are closely related to morphological and functional changes in podocytes. A series of morphological changes after podocyte injury in DN mainly include podocyte hypertrophy, podocyte epithelial-mesenchymal transdifferentiation, podocyte detachment, and podocyte apoptosis; functional changes mainly involve podocyte autophagy. More and more studies have shown that multiple signaling pathways play important roles in the progression of podocyte injury in DN. Here, we review research progress on the pathological mechanism of morphological and functional changes in podocytes associated with DN, to provide a new target for delaying the occurrence and development of this disorder.