Oridonin protects against the inflammatory response in diabetic nephropathy by inhibiting the TLR4/p38-MAPK and TLR4/NF-κB signaling pathways

Oridonin ameliorates renal fibrosis in diabetic nephropathy by inhibiting the Wnt/β-catenin signaling pathway

Diabetic nephropathy (DN) is one of the most serious and frequent complications among diabetes patients and presently constitutes vast the cases of end-stage renal disease worldwide. Tubulointerstitial fibrosis is a crucial factor related to the occurrence and progression of DN. Oridonin (Ori) is a diterpenoid derived from rubescens that has diverse pharmacological properties. Our previous study showed that Ori can protect against DN by decreasing the inflammatory response. However, whether Ori can alleviate renal fibrosis in DN remains unknown. Here, we investigated the mechanism through which Ori affects the Wnt/β-catenin signaling pathway in diabetic rats and human proximal tubular epithelial cells (HK-2) exposed to high glucose (HG) levels. Our results revealed that Ori treatment markedly decreased urinary protein excretion levels, improved renal function and alleviated renal fibrosis in diabetic rats. In vitro, HG treatment increased the migration of HK-2 cells while reducing their viability and proliferation rate, and treatment with Ori reversed these changes. Additionally, the knockdown of β-catenin arrested cell migration and reduced the expression levels of Wnt/β-catenin signaling-related molecules (Wnt4, p-GSK3β and β-catenin) and fibrosis-related molecules (α-smooth muscle actin, collagen I and fibronectin), and Ori treatment exerted an effect similar to that observed after the knockdown of β-catenin. Furthermore, the combination of Ori treatment and β-catenin downregulation exerted more pronounced biological effects than treatment alone. These findings may provide the first line of evidence showing that Ori alleviates fibrosis in DN by inhibiting the Wnt/β-catenin signaling pathway and thereby reveal a novel therapeutic avenue for treating tubulointerstitial fibrosis.

The mechanisms underlying Chinese medicines to treat inflammation in diabetic kidney disease

ETHNIC PHARMACOLOGICAL RELEVANCE

Diabetic kidney disease (DKD) is the main cause of end-stage renal disease (ESRD), which is a public health problem with a significant economic burden. Serious adverse effects, such as hypotension, hyperkalemia, and genitourinary infections, as well as increasing adverse cardiovascular events, limit the clinical application of available drugs. Plenty of randomized controlled trials(RCTs), meta-analysis(MAs) and systematic reviews(SRs) have demonstrated that many therapies that have been used for a long time in medical practice including Chinese patent medicines(CPMs), Chinese medicine prescriptions, and extracts are effective in alleviating DKD, but the mechanisms by which they work are still unknown. Currently, targeting inflammation is a central strategy in DKD drug development. In addition, many experimental studies have identified many Chinese medicine prescriptions, medicinal herbs and extracts that have the potential to alleviate DKD. And part of the mechanisms by which they work have been uncovered.

AIM OF THIS REVIEW

This review aims to summarize therapies that have been proven effective by RCTs, MAs and SRs, including CPMs, Chinese medicine prescriptions, and extracts. This review also focuses on the efficiency and potential targets of Chinese medicine prescriptions, medicinal herbs and extracts discovered in experimental studies in improving immune inflammation in DKD.

METHODS

We searched for relevant scientific articles in the following databases: PubMed, Google Scholar, and Web of Science. We summarized effective CPMs, Chinese medicine prescriptions, and extracts from RCTs, MAs and SRs. We elaborated the signaling pathways and molecular mechanisms by which Chinese medicine prescriptions, medicinal herbs and extracts alleviate inflammation in DKD according to different experimental studies.

RESULTS

After overviewing plenty of RCTs with the low hierarchy of evidence and MAs and SRs with strong heterogeneity, we still found that CPMs, Chinese medicine prescriptions, and extracts exerted promising protective effects against DKD. However, there is insufficient evidence to prove the safety of Chinese medicines. As for experimental studies, Experiments in vitro and in vivo jointly demonstrated the efficacy of Chinese medicines(Chinese medicine prescriptions, medicinal herbs and extracts) in DKD treatment. Chinese medicines were able to regulate signaling pathways to improve inflammation in DKD, such as toll-like receptors, NLRP3 inflammasome, Nrf2 signaling pathway, AMPK signaling pathway, MAPK signaling pathway, JAK-STAT, and AGE/RAGE.

CONCLUSION

Chinese medicines (Chinese medicine prescriptions, medicinal herbs and extracts) can improve inflammation in DKD. For drugs that are effective in RCTs, the underlying bioactive components or extracts should be identified and isolated. Attention should be given to their safety and pharmacokinetics. Acute, subacute, and subchronic toxicity studies should be designed to determine the magnitude and tolerability of side effects in humans or animals. For drugs that have been proven effective in experimental studies, RCTs should be designed to provide reliable evidence for clinical translation. In a word, Chinese medicines targeting immune inflammation in DKD are a promising direction.

Pathological mechanism of immune disorders in diabetic kidney disease and intervention strategies

Diabetic kidney disease is one of the most severe chronic microvascular complications of diabetes and a primary cause of end-stage renal disease. Clinical studies have shown that renal inflammation is a key factor determining kidney damage during diabetes. With the development of immunological technology, many studies have shown that diabetic nephropathy is an immune complex disease, and that most patients have immune dysfunction. However, the immune response associated with diabetic nephropathy and autoimmune kidney disease, or caused by ischemia or infection with acute renal injury, is different, and has a com-plicated pathological mechanism. In this review, we discuss the pathogenesis of diabetic nephropathy in immune disorders and the intervention mechanism, to provide guidance and advice for early intervention and treatment of diabetic nephropathy.

Reno-protective effect of nicorandil and pentoxifylline against potassium dichromate-induced acute renal injury via modulation p38MAPK/Nrf2/HO-1 and Notch1/TLR4/NF-κB signaling pathways

BACKGROUND

Occupational and environmental exposure to chromium compounds such as potassium dichromate (PDC) (K2Cr2O7) has emerged as a potential aetiologic cause for renal disease through apoptotic, and inflammatory reactions. The known potent antioxidants such as nicorandil (NIC) and/or pentoxifylline (PTX) were studied for their possible nephroprotective effect in PDC-treated rats.

METHODS

Forty male Wistar rats were divided into five groups; control, PDC group, NIC+PDC, PTX+PDC group, and combination+PDC group. Nephrotoxicity was evaluated histopathologically and biochemically. Invasive blood pressure, renal function parameters urea, creatinine, uric acid and albumin, glomerular filtration rate markers Cys-C, Kim-1 and NGAL, inflammatory markers IL-1β, IL-6, TNF-α, TGF-β, COX-II, p38MAPK, NF-κB and TLR4, oxidative stress SOD, GSH, MDA, MPO, HO-1 and Nrf2 and apoptotic mediators Notch1 and PCNA were evaluated. Besides, renal cortical histopathology was assayed as well.

RESULTS

PDC led to a considerable increase in indicators for kidney injury, renal function parameters, invasive blood pressure, oxidative stress, and inflammatory markers. They were markedly reduced by coadministration of PDC with either/or NIC and PTX. The NIC and PTX combination regimen showed a more significant improvement than either medication used alone. Our results demonstrated the nephroprotective effect of NIC, PTX, and their combined regimen on PDC-induced kidney injury through suppression of oxidative stress, apoptosis, and inflammatory response.

CONCLUSION

Renal recovery from PDC injury was achieved through enhanced MAPK/Nrf2/HO-1 and suppressed Notch1/TLR4/NF-κB signaling pathways. This study highlights the role of NIC and PTX as effective interventions to ameliorate nephrotoxicity in patients undergoing PDC toxicity.

Oridonin Inhibits Mycobacterium marinum Infection-Induced Oxidative Stress In Vitro and In Vivo

Prior to the COVID-19 pandemic, tuberculosis (TB) was the leading cause of death globally attributable to a single infectious agent, ranking higher than HIV/AIDS. Consequently, TB remains an urgent public health crisis worldwide. Oridonin (7a,20-Epoxy-1a,6b,7,14-tetrahydroxy-Kaur-16-en-15-one Isodonol, C₂₀H₂₈O₆, Ori), derived from the Rabdosia Rrubescens plant, is a natural compound that exhibits antioxidant, anti-inflammatory, and antibacterial properties. Our objective was to investigate whether Ori's antioxidant and antibacterial effects could be effective against the infection Mycobacterium marinum (Mm)-infected cells and zebrafish. We observed that Ori treatment significantly impeded Mm infection in lung epithelial cells, while also suppressing inflammatory response and oxidative stress in Mm-infected macrophages. Further investigation revealed that Ori supplementation inhibited the proliferation of Mm in zebrafish, as well as reducing oxidative stress levels in infected zebrafish. Additionally, Ori promoted the expression of NRF2/HO-1/NQO-1 and activated the AKT/AMPK-α1/GSK-3β signaling pathway, which are both associated with anti-inflammatory and antioxidant effects. In summary, our results demonstrate that Ori exerts inhibitory effects on Mm infection and proliferation in cells and zebrafish, respectively. Additionally, Ori regulates oxidative stress by modulating the NRF2/HO-1/NQO-1 and AKT/AMPK-α1/GSK-3β signaling pathways.

Oridonin Attenuates Thioacetamide-Induced Osteoclastogenesis Through MAPK/NF-κB Pathway and Thioacetamide-Inhibited Osteoblastogenesis Through BMP-2/RUNX2 Pathway

Osteoporosis, an age-related metabolic bone disease, is mainly caused by an imbalance between osteoblast-mediated bone formation and osteoclast-mediated bone resorption. At present, there are many osteoporosis drugs that can promote bone formation or inhibit bone resorption. However, there were few therapeutic drugs that can simultaneously promote bone formation and inhibit bone resorption. Oridonin (ORI), a tetracyclic diterpenoid compound isolated from Rabdosia rubescens, has been proved to have anti-inflammatory, anti-tumor effects. However, little is known about the osteoprotective effect of oridonin. Thioacetamide (TAA) is a common organic compound with significant hepatotoxicity. Recent studies have found that there was a certain association between TAA and bone injury. In this work, we investigated the effect and mechanism of ORI on TAA-induced osteoclastogenesis and inhibition of osteoblast differentiation. The results showed that TAA could promote the osteoclastogenesis of RAW264.7 by promoting the MAPK/NF-κB pathway, and also promoted p65 nuclear translocation and activated intracellular ROS generation, and ORI can inhibit these effects to inhibit TAA-induced osteoclastogenesis. Moreover, ORI can also promote the osteogenic differentiation pathway and inhibit adipogenic differentiation of BMSCs to promote bone formation. In conclusion, our results revealed that ORI, as a potential therapeutic drug for osteoporosis, could protect against TAA-induced bone loss and TAA-inhibited bone formation.

rFGF4 alleviates lipopolysaccharide-induced acute lung injury by inhibiting the TLR4/NF-κB signaling pathway

Acute lung injury (ALI) is a serious and common clinical disease. Despite significant progress in ALI treatment, the morbidity and mortality rates remain high. However, no effective drug has been discovered for ALI. FGF4, a member of the FGF family, plays an important role in the regulation of various physiological and pathological processes. Therefore, in the present study, we aimed to study the protective effects of FGF4 against LPS-induced lung injury in vivo and in vitro. We found that rFGF4 treatment improved the lung W/D weight ratio, the survival rate, immune cell infiltration and protein concentrations in mice with LPS-induced ALI. Histological analysis revealed that rFGF4 significantly attenuated lung tissue injury and cell apoptosis. Furthermore, rFGF4 inhibited the activation of the TLR4/NF-κB signaling pathway and the production of pro-inflammatory mediators in LPS-injured lung tissues, murine alveolar macrophages (MH-S) and murine pulmonary epithelial (MLE-12) cells. The results of cell experiments further verified that rFGF4 inhibited the production of inflammatory mediators in MH-S cells and MLE-12 cells by regulating the TLR4/NF-κB signaling pathway. These results revealed that rFGF4 protected lung tissues and inhibited inflammatory mediators in mice with LPS-induced ALI by inhibiting the TLR4/NF-κB signaling pathway in MH-S and MLE-12 cells.

A natural products solution to diabetic nephropathy therapy

Diabetic nephropathy is one of the most common complications in diabetes. It has been shown to be the leading cause of end-stage renal disease. However, due to their complex pathological mechanisms, effective therapeutic drugs other than angiotensin-converting enzyme inhibitors (ACEIs) and angiotensin receptor blockers (ARBs), which have been used for 20 years, have not been developed so far. Recent studies have shown that diabetic nephropathy is characterized by multiple signalling pathways and multiple targets, including inflammation, apoptosis, pyroptosis, autophagy, oxidative stress, endoplasmic reticulum stress and their interactions. It definitely exacerbates the difficulty of therapy, but at the same time it also brings out the chance for natural products treatment. In the most recent two decades, a large number of natural products have displayed their potential in preclinical studies and a few compounds are under invetigation in clinical trials. Hence, many compounds targeting these singals have been emerged as a comprehensive blueprint for treating strategy of diabetic nephropathy. This review focuses on the cellular and molecular mechanisms of natural prouducts that alleviate this condition, including preclinical studies and clinical trials, which will provide new insights into the treatment of diabetic nephropathy and suggest novel ideas for new drug development.

The extract of Polygala fallax Hemsl. slows the progression of diabetic nephropathy by targeting TLR4 anti-inflammation and MMP-2/9-mediated anti-fibrosis in vitro

BACKGROUND

Polygala fallax Hemsl. is a plant that is commonly used as a folk medicine by Guangxi ethnic minorities, and it is also widely used in the clinical treatment of chronic diseases in China. The extract of P. fallax (EPF) contains key biologically active components from the roots and stems. However, the role of P. fallax or EPF in diabetic nephropathy (DN) is unclear.

PURPOSE

This study aimed to investigate the effects and mechanisms of EPF on high glucose (HG)-induced human glomerular mesangial cell (HMC) injury, inflammation, fibrosis, and apoptosis in vitro.

METHODS

For the in vitro study, MTT and ELISA assays were performed with HG-treated HMCs, as well as MMP, Hoechst, flow cytometry, qRT-PCR, and western blot analyses. The expression of the TLR4/NF-κB pathway, along with its downstream inflammatory, apoptosis, and fibrosis factors, was measured. The expression of the TLR4/NF-κB pathway and its downstream inflammatory factors were also measured after the addition of TLR4 inhibitors.

RESULTS

Our results suggest that EPF can reverse the hyperproliferation and apoptosis of HMCs induced by HG. In addition, the extract inhibited the increase in inflammatory factors IL-6, TNF-α, IL-1β, MCP-1, and IL-18 in cells treated with HG. The mRNA and protein expression of TLR4, MyD88, NF-κB, Col IV, FN, MMP-9, and MMP-2 were downregulated by EPF. In addition, EPF significantly reduced the loss of MMP and the upregulation of Bcl-2/Bax mRNA and protein levels after HG treatment.

CONCLUSION

These results demonstrated that EPF protects against diabetes-induced renal injury in vitro. EPF protected against HG-induced HMCs proliferation, apoptosis, fibrosis, and inflammation likely via inhibition of TLR4-dependent NF-κB signaling. This herbal extract may also be a novel treatment for DN.

Immune responses in diabetic nephropathy: Pathogenic mechanisms and therapeutic target

Diabetic nephropathy (DN) is a chronic, inflammatory disease affecting millions of diabetic patients worldwide. DN is associated with proteinuria and progressive slowing of glomerular filtration, which often leads to end-stage kidney diseases. Due to the complexity of this metabolic disorder and lack of clarity about its pathogenesis, it is often more difficult to diagnose and treat than other kidney diseases. Recent studies have highlighted that the immune system can inadvertently contribute to DN pathogenesis. Cells involved in innate and adaptive immune responses can target the kidney due to increased expression of immune-related localization factors. Immune cells then activate a pro-inflammatory response involving the release of autocrine and paracrine factors, which further amplify inflammation and damage the kidney. Consequently, strategies to treat DN by targeting the immune responses are currently under study. In light of the steady rise in DN incidence, this timely review summarizes the latest findings about the role of the immune system in the pathogenesis of DN and discusses promising preclinical and clinical therapies.

Diabetic Kidney Disease: From Pathogenesis to Novel Treatment Possibilities

One of the microvascular complications of diabetes is diabetic kidney disease (DKD), often leading to end stage renal disease (ESRD) in which patients require costly dialysis or transplantation. The silent onset and irreversible progression of DKD are characterized by a steady decline of the estimated glomerular filtration rate, with or without concomitant albuminuria. The diabetic milieu allows the complex pathophysiology of DKD to enter a vicious cycle by inducing the synthesis of excessive amounts of reactive oxygen species (ROS) causing oxidative stress, inflammation, and fibrosis. As no cure is available, intensive research is required to develop novel treatments possibilities. This chapter provides an overview of the important pathomechanisms identified in diabetic kidney disease, the currently established therapies, as well as recently developed novel therapeutic strategies in DKD.

Carpelipines C and D, Two Anti-Inflammatory Germacranolides from the Flowers of Carpesium lipskyi Winkl. (Asteraceae)

Two new germacranolides, carpelipine C (1) and carpelipine D (2), together with four known ones (3-6), were isolated from Carpesium lipskyi Winkl. flowers, a folk Tibetan herbal medicine with antipyretic-analgesic and anti-inflammatory effects. The chemical structures of new structure were illuminated by diversified spectroscopic and X-ray crystallographic analyses. Compounds 1 and 3 dramatically suppressed the synthesis of NO and decreased pre-inflammatory protein expression of iNOS and COX-2 in LPS-induced RAW264.7 cells. Furthermore, it was revealed that NF-κB/MAPK signaling pathway were involved in the anti-inflammatory process of 1 and 3, and their effects on reducing oxidative stress by activating Nrf2/HO-1 pathway were also measured. This article indicated that the traditional use of C. lipskyi to treat inflammatory diseases has a certain rationality.

Discovery of oridonin as a novel agonist for BRS-3

BACKGROUND

Bombesin Receptor Subtype-3 (BRS-3, Bombesin-like receptor, BB₃) is an orphan G-protein coupled receptor (GPCR). Recent studies have shown that BRS-3 played a vital role in glucose regulation, insulin secretion, and energy homeostasis. Therefore, discovering more novel exogenous ligands with diverse structures for BRS-3 will be of great importance for target validation and drug development.

PURPOSE

In this study, we aim to discover new agonists of BRS-3 from our natural compound libraries, providing a new probe to study the function of BRS-3.

STUDY DESIGN

Multiple cell-based assays and in vivo experiments were performed to identify the new ligand.

METHODS

BRS-3 overexpression cells were coupled with FLIPR assay, homogeneous time-resolved fluorescence (HTRF) IP-ONE assay, dynamic mass redistribution (DMR) assay, β-arrestin2 recruitment assay, and western blot to determine receptor activation and downstream signaling events. To further validate the target of BRS-3, a series of in vitro and in vivo experiences were conducted, including glucose uptake, glucose transporter type 4 (GLUT4) transportation in C2C12, and oral glucose tolerance test (OGTT) in mice.

RESULTS

We discovered and identified oridonin as a novel small molecule agonist of BRS-3, with a moderate affinity (EC₅₀ of 2.236 × 10^-7 M in calcium mobilization assay), specificity, and subtype selectivity. Further in vitro and in vivo tests demonstrated that oridonin exerted beneficial effects in glucose homeostasis through activating BRS-3.

CONCLUSIONS

Oridonin, as the discovered new ligand of BRS-3, provides a valuable tool compound to investigate BRS-3's function, especially for target validation in type 2 diabetes and obesity. Oridonin is promising as a lead compound in the treatment of metabolic disorders. Compared to the known agonists of BRS-3, we can take advantage of the multiple reported pharmacological activities of ODN as a natural product and assess whether these pharmacological activities are regulated by BRS-3. This may facilitate the discovery of novel functions of BRS-3.

Oridonin Attenuates Cisplatin-Induced Acute Kidney Injury via Inhibiting Oxidative Stress, Apoptosis, and Inflammation in Mice

The use of cisplatin, a chemotherapy drug, is often limited due to its renal side effects such as acute kidney injury (AKI). However, there are no validated medications to prevent or treat cisplatin-induced AKI. Oridonin is the major bioactive component of Isodon rubescens (Rabdosia rubescens) and exhibits anticancer, antioxidative, and anti-inflammatory effects. Recent studies have shown that oridonin alleviated a variety of inflammatory diseases, including renal diseases, in rodents. This study was aimed at investigating the potential renoprotective effect of oridonin on cisplatin-induced AKI. Male C57BL/6 mice were administered with cisplatin (20 mg/kg) with or without oridonin (15 mg/kg). Oridonin administration to mice after cisplatin injection attenuated renal dysfunction and histopathological changes. Upregulation of tubular injury markers was also suppressed by oridonin. Mechanistically, oridonin suppressed lipid peroxidation and reversed the decreased ratio of reduced to oxidized glutathione in cisplatin-injected mice. The increase in cisplatin-induced apoptosis was also alleviated by the compound. Moreover, oridonin inhibited cytokine overproduction and attenuated immune cell infiltration in cisplatin-injected mice. Altogether, these data demonstrated that oridonin alleviates cisplatin-induced kidney injury via inhibiting oxidative stress, apoptosis, and inflammation.

Oridonin attenuates LPS-induced early pulmonary fibrosis by regulating impaired autophagy, oxidative stress, inflammation and EMT

CONTEXT

Oridonin (Ori) possesses anti-inflammatory, antioxidant and antitumor properties. However, the effects of Ori on Lipopolysaccharide (LPS)-induced early pulmonary fibrosis remain unclear.

OBJECTIVE

We evaluated the protective effects of Ori on the mice model of pulmonary fibrosis.

MATERIALS AND METHODS

The BALB/C mice were given LPS (1 mg/kg) or Ori (20 mg/kg) according to experimental grouping. Then the left lung tissues were used for HE, immunohistochemical and Masson staining, and the right lung tissues were used for hydroxyproline measurement and western blot experiments. Bronchoalveolar lavage fluid was collected for Giemsa staining.

RESULTS

The high levels of hydroxyproline induced by LPS were reduced by Ori treatment. Immunohistochemical staining and western blot analysis showed that Ori inhibited the increased levels of fibrosis-related proteins (α-smooth muscle actin, transforming growth factor-β, Collagen Ⅰ and phosphorylated-smad). Additionally, Ori treatment increased E-cadherin levels and decreased in Snail and Slug levels. Besides, Ori could suppress LPS-induced the infiltration of neutrophils and activation of the NLRP3 inflammasome. In addition, LPS caused the upregulation of NADPH oxidase 4 and exacerbated lung fibrosis. As the activator of NF-E2 related factor-2, Ori exerted protective effects in this animal model. Moreover, Ori reversed the LPS-triggered increases in Beclin-1, P62/sequestosome 1, autophagy related 3 and LC3.

CONCLUSIONS

These findings suggested that Ori protected against LPS-induced early pulmonary fibrosis by inhibiting NLRP3-dependent inflammation, NADPH oxidase 4-dependent oxidative stress, the impaired autophagy and epithelial mesenchymal transformation.

Isodon rubescens (Hemls.) Hara.: A Comprehensive Review on Traditional Uses, Phytochemistry, and Pharmacological Activities

Isodon rubescens is a medicinal and food plant, often eaten as a wild vegetable in ancient China, and has been widely used for decades to treat sore throats, tonsillitis, colds and headaches, bronchitis, chronic hepatitis, joint rheumatism, snake and insect bites, and various cancers. This comprehensive and systematic review of the ethnomedicinal uses, phytochemical composition, pharmacological activity, quality control and toxicology of I. rubescens provides updated information for the further development and application in the fields of functional foods and new drugs research. To date, a total of 324 substances have been isolated and identified from the plant, including terpenoids, flavonoids, polyphenols, alkaloids, amino acids, and volatile oils. Among these substances, diterpenoids are the most important and abundant bioactive components. In the past decades pharmacological studies have shown that I. rubescens has significant biological activities, especially in the modulation of antitumor and multidrug resistance. However, most of these studies have been conducted in vitro. In-depth in vivo studies on the quality control of its crude extracts and active ingredients, as well as on metabolite identification are still very limited. Therefore, more well-designed preclinical and clinical studies are needed to confirm the reported therapeutic potential of I. rubescens.

Correlation analysis of serum IGF-1 and IL-6 and urinary albumin/creatinine ratio in patients with type 2 diabetic kidney disease

OBJECTIVES

Diabetic kidney disease (DKD) is one of the most common chronic complications in diabetic patients, and there are major limitations in its pathological diagnosis. This study's objectives were to examine the changes in serum insulin-like growth factor-1 (IGF-1) and interleukin-6 (IL-6) levels in DKD patients with various urinary albumin/creatinine ratio (ACR) and to evaluate the utility of these two biological markers in the clinical diagnosis of the condition.

METHODS

We chose 80 type 2 diabetic patients as the experimental group and 20 healthy normal participants as the control group. The experimental group was split into three groups based on the ACR range: diabetes without nephropathy group (ACR < 30 mg/g), microalbuminuric group (30 < ACR < 300 mg/g), and macroalbuminuric group (ACR > 300 mg/g). The levels of serum IL-6 and IGF-1 were assessed in each trial participant.

RESULTS

Serum IGF-1 was higher in the experimental group than in the control group (P < 0.01), and serum IL-6 levels were also higher than in the control group (P < 0.001). In DKD patients, serum levels of IL-6 and IGF-1 tended to rise when ACR levels rose. By Pearson correlation analysis, serum IGF-1 and IL-6 were positively correlated with ACR (r = 0.765 and r = 0.651, all P < 0.001) and negatively correlated with eGFR (r = -0.389 and r = -0.364, all P < 0.01). Additionally, the receiver operating characteristic (ROC) characteristic curve showed that the area under the curve (AUC) values for serum IGF-1 and IL-6 were 0.9056 and 0.7850, respectively, while the AUR value for both combined was 0.9367.

CONCLUSION

Serum IGF-1 and IL-6 levels can be used to diagnose DKD, and the combined analysis of these two indicators can improve the sensitivity and specificity of the disease diagnosis.

Bioinformatics Analysis of the Mechanisms of Diabetic Nephropathy via Novel Biomarkers and Competing Endogenous RNA Network

Diabetic nephropathy (DN) is one of the common chronic complications of diabetes with unclear molecular mechanisms, which is associated with end-stage renal disease (ESRD) and chronic kidney disease (CKD). Our study intended to construct a competing endogenous RNA (ceRNA) network via bioinformatics analysis to determine the potential molecular mechanisms of DN pathogenesis. The microarray datasets (GSE30122 and GSE30529) were downloaded from the Gene Expression Omnibus database to find differentially expressed genes (DEGs). GSE51674 and GSE155188 datasets were used to identified the differentially expressed microRNAs (miRNAs) and long non-coding RNAs (lncRNAs), respectively. The DEGs between normal and DN renal tissues were performed using the Linear Models for Microarray (limma) package. Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway enrichment analyses were performed to reveal the mechanisms of DEGs in the progression of DN. The protein-protein interactions (PPI) of DEGs were carried out by STRING database. The lncRNA-miRNA-messenger RNA (mRNA) ceRNA network was constructed and visualized via Cytoscape on the basis of the interaction generated through the miRDB and TargetScan databases. A total of 94 significantly upregulated and 14 downregulated mRNAs, 31 upregulated and 121 downregulated miRNAs, and nine upregulated and 81 downregulated lncRNAs were identified. GO and KEGG pathways enriched in several functions and expression pathways, such as inflammatory response, immune response, identical protein binding, nuclear factor kappa b (NF-κB) signaling pathway, and PI3K-Akt signaling pathway. Based on the analysis of the ceRNA network, five differentially expressed lncRNAs (DElncRNAs) (SNHG6, KCNMB2-AS1, LINC00520, DANCR, and PCAT6), five DEmiRNAs (miR-130b-5p, miR-326, miR-374a-3p, miR-577, and miR-944), and five DEmRNAs (PTPRC, CD53, IRF8, IL10RA, and LAPTM5) were demonstrated to be related to the pathogenesis of DN. The hub genes were validated by using receiver operating characteristic curve (ROC) and real-time PCR (RT-PCR). Our research identified hub genes related to the potential mechanism of DN and provided new lncRNA-miRNA-mRNA ceRNA network that contributed to diagnostic and potential therapeutic targets for DN.

Diacerein attenuates vascular dysfunction by reducing inflammatory response and insulin resistance in type 2 diabetic rats

AIM

To examine the effect of diacerein on vascular dysfunction in type 2 diabetic rats and elucidate the mechanism of diacerein.

METHODS

In a rat model, type 2 diabetes was induced by high-fat diet and streptozotocin. Vascular function was assessed in vascular reactivity experiment. The effect of diacerein (10 or 20 mg/kg/day) on blood glucose, inflammation and insulin signaling, and modulators in vascular tissue in diabetic rats were investigated by molecular and biochemical approaches.

RESULTS

In this study, diacerein inhibited diabetes-induced vascular dysfunction. Diacerein treatment normalized blood glucose, insulin tolerance test, inflammatory cytokine levels and nitric oxide synthases expression in diabetic rats. Moreover, diacerein inhibited NF-κB and NLRP3 pathways and activated insulin signaling pathway related proteins IRS-1 and AKT in diabetic rats.

CONCLUSION

Diacerein improved vascular function effectively in diabetic rats by suppressing inflammation and reducing insulin resistance. These results suggest that diacerein may represent a novel therapy for patients with diabetes.

Oridonin inhibits SASP by blocking p38 and NF-κB pathways in senescent cells

Cellular senescence is a state of irreversible cell growth arrest that functions as a biological defense mechanism against severe DNA damage. Senescent cells with DNA damage produce pro-inflammatory cytokines, such as IL-6 and IL-8, and this phenomenon is called the senescence-associated secretory phenotype (SASP). SASP factors have been implicated in various disorders, including cancer. We performed a screening assay and identified oridonin as a candidate SASP inhibitor. Oridonin is an active diterpenoid that is isolated from Isodon plants and has been reported to exhibit anti-inflammatory, antibacterial, antioxidant, and antitumor activities. It reduced the secretion of IL-6 and IL-8 in senescent cells at the protein and mRNA levels. Oridonin also inhibited p65 subunit of NF-κB activity. However, oridonin did not affect SA β-gal activity and enhanced the expression of p21. The expression and phosphorylation of p38 were down-regulated by oridonin. The p38 inhibitor SB203580 inhibited the secretion of IL-8, slightly inhibited the secretion of IL-6, and did not affect NF-κB activity. Therefore, the NF-κB and p38 pathways may contribute to the inhibition of SASP by oridonin. Oridonin has potential as a therapeutic agent for SASP-related diseases.

Resolving hepatic fibrosis via suppressing oxidative stress and an inflammatory response using a novel hyaluronic acid modified nanocomplex

Hepatic fibrosis remains a serious threat to human health globally and there are no effective antifibrotic pharmacotherapeutic strategies, to date. Upon the activation of hepatic stellate cells, excess deposition of the extracellular matrix occurs, acting as a trigger that generates reactive oxygen species and an inflammatory response, thereby exacerbating the development of hepatic fibrosis and inflammation. In this study, we incorporated an idea that targets key pathways for developing novel anti-fibrosis nanomedicine. Previous studies have reported the potential of LY294002 (LY) as a PI3K/Akt inhibitor that suppresses the HSC activation and fibrosis development; however, its poor water solubility impedes further investigation. Moreover, the proliferation of HSC, severe oxidative stress and inflammatory conditions could be undermined by oridonin (ORD) treatment. Herein, we developed an HA-ORD/LY-Lips nanocomplex, where LY294002 was encapsulated into liposomes to prepare LY-Lips while ORD was conjugated with a hyaluronic acid (HA) polymer acting as a prodrug HA-ORD. The complex exerts great potential in improving the liver-targeted drug release. We adopted a series of in vitro and in vivo evaluations which demonstrate that HA-ORD/LY-Lips can significantly avert activation of hepatic stellate cells via scavenging reactive oxygen species and suppressing an inflammatory response. Our work implements a proof of concept strategy for fibrosis treatment based on the dual antioxidative and anti-inflammatory mechanisms, which may be applicable to treat liver fibrosis associated with a dysregulated inflammatory microenvironment.

The role of discoidin domain receptor 2 in the renal dysfunction of alport syndrome mouse model

Alport syndrome (AS) is a hereditary glomerular nephritis caused by mutation in one of the type IV collagen genes α3/α4/α5 that encode the heterotrimer COL4A3/4/5. Failure to form a heterotrimer due to mutation leads to the dysfunction of the glomerular basement membrane, and end-stage renal disease. Previous reports have suggested the involvement of the receptor tyrosine kinase discoidin domain receptor (DDR) 1 in the progression of AS pathology. However, due to the similarity between DDR1 and DDR2, the role of DDR2 in AS pathology is unclear. Here, we investigated the involvement of DDR2 in AS using the X-linked AS mouse model. Mice were treated subcutaneously with saline or antisense oligonucleotide (ASO; 5 mg/kg or 15 mg/kg per week) for 8 weeks. Renal function parameters and renal histology were analyzed, and the gene expressions of inflammatory cytokines were determined in renal tissues. The expression level of DDR2 was highly elevated in kidney tissues of AS mice. Knockdown of Ddr2 using Ddr2-specific ASO decreased the Ddr2 expression. However, the DDR2 ASO treatment did not improve the proteinuria or decrease the BUN level. DDR2 ASO also did not significantly ameliorate the renal injury, inflammation and fibrosis in AS mice. These results showed that Ddr2 knockdown by ASO had no notable effect on the progression of AS indicating that DDR2 may not be critically involved in AS pathology. This finding may provide useful information and further understanding of the role of DDRs in AS.

Ganoderma lucidum ameliorates the diabetic nephropathy via down-regulatory effect on TGFβ-1 and TLR-4/NFκB signalling pathways

OBJECTIVES

Diabetic nephropathy (DN) is one of the most important complications of diabetes mellitus and it is considered as a principal cause for end-stage renal failure. Ganoderma lucidum (GL) has been studied for its reno-protective effect against different kidney injury models. The aim of our study is to investigate the mechanisms by which GL can improve kidney injury and consequent renal inflammation and fibrosis.

METHODS

GL either in a low dose (250 mg/kg, i.p.) or high dose (500 mg/kg, i.p.) was administered to DN rat model, and nephropathy indices were investigated.

KEY FINDINGS

GL treatment significantly down-regulated kidney injury molecule-1 (KIM-1) gene expression and inhibited TLR-4 (Toll-like receptor-4)/NFκB (nuclear factor kappa B) signalling pathway. As well, GL treatment significantly decreased the pro-inflammatory mediator; IL-1β (interleukin-1 beta) level and fibrosis-associated growth factors; FGF-23 (fibroblast growth factor-23) and TGFβ-1 (transforming growth factor beta-1) levels. In addition, GL remarkably inhibited (Bax) the pro-apoptotic protein and induced (Bcl-2) the anti-apoptotic protein expression in kidneys. Moreover, GL treatment significantly alleviates kidney injury indicated by correcting the deteriorated kidney function and improving oxidative stress status in DN rats.

CONCLUSIONS

GL significantly improved renal function indices through dose-dependent kidney function restoration, oxidative stress reduction, down-regulation of gene expression of KIM-1 and TLR4/NFκB signalling pathway blockage with subsequent alleviation of renal inflammation and fibrosis.

Oridonin: A Review of Its Pharmacology, Pharmacokinetics and Toxicity

Oridonin, as a natural terpenoids found in traditional Chinese herbal medicine Isodon rubescens (Hemsl.) H.Hara, is widely present in numerous Chinese medicine preparations. The purpose of this review focuses on providing the latest and comprehensive information on the pharmacology, pharmacokinetics and toxicity of oridonin, to excavate the therapeutic potential and explore promising ways to balance toxicity and efficacy of this natural compound. Information concerning oridonin was systematically collected from the authoritative internet database of PubMed, Elsevier, Web of Science, Wiley Online Library and Europe PMC applying a combination of keywords involving "pharmacology," "pharmacokinetics," and "toxicology". New evidence shows that oridonin possesses a wide range of pharmacological properties, including anticancer, anti-inflammatory, hepatorenal activities as well as cardioprotective protective activities and so on. Although significant advancement has been witnessed in this field, some basic and intricate issues still exist such as the specific mechanism of oridonin against related diseases not being clear. Moreover, several lines of evidence indicated that oridonin may exhibit adverse effects, even toxicity under specific circumstances, which sparked intense debate and concern about security of oridonin. Based on the current progress, future research directions should emphasize on 1) investigating the interrelationship between concentration and pharmacological effects as well as toxicity, 2) reducing pharmacological toxicity, and 3) modifying the structure of oridonin-one of the pivotal approaches to strengthen pharmacological activity and bioavailability. We hope that this review can provide some inspiration for the research of oridonin in the future.

An Overview of the Posttranslational Modifications and Related Molecular Mechanisms in Diabetic Nephropathy

Diabetic nephropathy (DN), a common diabetic microvascular complication, is characterized by its complex pathogenesis, higher risk of mortality, and the lack of effective diagnosis and treatment methods. Many studies focus on the diagnosis and treatment of diabetes mellitus (DM) and have reported that the pathophysiology of DN is very complex, involving many molecules and abnormal cellular activities. Given the respective pivotal roles of NF-κB, Nrf2, and TGF-β in inflammation, oxidative stress, and fibrosis during DN, we first review the effect of posttranslational modifications on these vital molecules in DN. Then, we describe the relationship between these molecules and related abnormal cellular activities in DN. Finally, we discuss some potential directions for DN treatment and diagnosis. The information reviewed here may be significant in the design of further studies to identify valuable therapeutic targets for DN.

Hepatoprotective effects of oridonin against bisphenol A induced liver injury in rats via inhibiting the activity of xanthione oxidase

Bisphenol A (BPA) is widely used to manufacture packaging materials for various daily necessities and causes harmful effects in organs, especially liver injury, by generating oxidative stress. Oridonin, an active diterpenoid isolated from Rabdosia rubescens (Hemsl.) Hara, has been reported to possess a wide range of pharmacological activities including anti-inflammatory, antioxidative and antiapoptotic effects. However, the role of oridonin in BPA--induced liver injury and its potential protective mechanism have not been well characterized. In this research, we explored the metabolic alterations in the liver tissue of rats after exposure to BPA with or without pretreatment with oridonin for 14 days by metabolomics analysis based on UPLC-MS/MS. Rats were randomly divided into groups as follows: Control, Vehicle, Oridonin (10 mg/kg), Bisphenol A (500 mg/kg), bisphenol A + Oridonin (500 + 10 mg/kg), Bisphenol A + Diammonium glycyrrhizinate (500 + 40 mg/kg). The biochemical results showed that oridonin significantly reduced the levels of AST and ALT (P < 0.05), ameliorated the abnormal histopathological changes and reduced hepatic apoptosis compared with the BPA group. Furthermore, metabolomics results revealed that purine metabolism, phenylalanine, tyrosine and tryptophan biosynthesis and phenylalanine metabolism were reprogrammed, based on 28 identified significant differential metabolites among the Vehicle, BPA and BPA + oridonin groups. In-depth studies demonstrated that pretreatment with oridonin may play a protective role by restoring BPA-induced changes in oxidative stress and the activity of oxidase (XOD) (P < 0.05). Additionally, oridonin could inhibit the activity of XOD by binding to it, therefore decreasing the reactive oxygen species (ROS) level, upregulating the content of hypoxanthine and xanthine, and reducing the level of uric acid in the liver (P < 0.05). This research presents the potential protective mechanisms of oridonin on BPA-induced liver injury at the metabolic level, which might be used to identify new protective agents that prevent BPA-induced liver injury.

Overview of key molecular and pharmacological targets for diabetes and associated diseases

Diabetes epidemiological quantities are demonstrating one of the most important communities' health worries. The essential diabetic difficulties are including cardiomyopathy, nephropathy, inflammation, and retinopathy. Despite developments in glucose decreasing treatments and drugs, these diabetic complications are still ineffectively reversed or prohibited. Several signaling and molecular pathways are vital targets in the new therapies of diabetes. This review assesses the newest researches about the key molecules and signaling pathways as targets of molecular pharmacology in diabetes and diseases related to it for better treatment based on molecular sciences. The disease is not cured by current pharmacological strategies for type 2 diabetes. While several drug combinations are accessible that can efficiently modulate glycemia and mitigate long-term complications, these agents do not reverse pathogenesis, and in practice, they are not established to modify the patient's specific molecular profiling. Therapeutic companies have benefited from human genetics. Genome exploration, which is agnostic to the information that exists, has revealed tens of loci that impact glycemic modulation. The physiological report has begun to examine subtypes of diseases, illustrate heterogeneity and propose biochemical therapeutic pathways.

Renoprotective Effect of Oridonin in a Mouse Model of Acute Kidney Injury via Suppression of Macrophage Involved Inflammation

Ischemia-reperfusion injury (IRI) is the major cause of acute kidney injury (AKI). The previous studies demonstrated that Oridonin can protect kidney against IRI-induced AKI, but the underlying molecular mechanism is unclear. In this study, it showed that Oridonin significantly improved kidney damage, and inhibited the expression of interleukin (IL)-1β, IL-6, tumor necrosis factor (TNF)-α and MCP-1, as well as macrophage marker F4/80 in kidney and the secretion of inflammatory cytokins in serum of AKI mice in vivo. In addition, Oridonin also effectively reduced the expression and secretion of lipopolysaccharide (LPS)-induced inflammatory factors in macrophage cell line RAW264.7 in vitro. Notably, Oridonin strongly downregulated Mincle and AKT/nuclear factor-kappaB (NF-κB) signaling both in vivo and in vitro, and the results of cellular recovery experiments of overexpression of Mincle in macrophage suggested that Oridonin suppressed inflammatory response of macrophage through inhibiting Mincle, which may be the underlying mechanism of Oridonin improving injury in kidney of AKI mice. In summary, the above results indicated that Oridonin can protect kidney from IRI-induced inflammation and injury by inhibiting the expression of Mincle in macrophage.

HLA-A2.1-restricted ECM1-derived epitope LA through DC cross-activation priming CD8+ T and NK cells: a novel therapeutic tumour vaccine

Background

CD8⁺ T cell-mediated adaptive cellular immunity and natural killer (NK) cell-mediated innate immunity both play important roles in tumour immunity. This study aimed to develop therapeutic tumour vaccines based on double-activation of CD8⁺ T and NK cells.

Methods

The immune Epitope database, Molecular Operating Environment software, and enzyme-linked immunosorbent assay were used for epitope identification. Flow cytometry, confocal microscopy, UPLC-QTOF-MS, and RNA-seq were utilized for evaluating immunity of PBMC-derived DCs, CD8⁺ T or NK cells and related pathways. HLA-A2.1 transgenic mice combined with immunologically reconstituted tumour-bearing mice were used to examine the antitumour effect and safety of epitope vaccines.

Results

We identified novel HLA-A2.1-restricted extracellular matrix protein 1(ECM1)-derived immunodominant epitopes in which LA induced a potent immune response. We also found that LA-loaded DCs upregulated the frequency of CD3⁺/CD8⁺ T cells, CD45RO⁺/CD69⁺ activated memory T cells, and CD3⁻/CD16⁺/CD56⁺ NK cells. We demonstrated cytotoxic granule release of LA/DC-CTLs or LA/DC-NK cells and cytotoxicity against tumour cells and microtissue blocks via the predominant IFN-γ/perforin/granzyme B cell death pathway. Further investigating the mechanism of LA-mediated CD8⁺ T activation, we found that LA could be internalized into DCs through phagocytosis and then formed a LA-MHC-I complex presented onto the DC surface for recognition of the T cell receptor to upregulate Zap70 phosphorylation levels to further activate CD8⁺ T cells by DC-CTL interactions. In addition, LA-mediated DC-NK crosstalk through stimulation of the TLR4-p38 MAPK pathway increased MICA/B expression on DCs to interact with NKG2D for NK activation. Promisingly, LA could activate CD8⁺ T cells and NK cells simultaneously via interacting with DCs to suppress tumours in vivo. Moreover, the safety of LA was confirmed.

Conclusions

LA-induced immune antitumour activity through DC cross-activation with CD8⁺ T and NK cells, which demonstrated proof-of-concept evidence for the capability and safety of a novel therapeutic tumour vaccine.

Supplementary Information

The online version contains supplementary material available at 10.1186/s13045-021-01081-7.

Medicinal plants and bioactive natural products as inhibitors of NLRP3 inflammasome

The NLR family, pyrin domain-containing 3 (NLRP3) inflammasome is a multiprotein complex that induces caspase-1 activation and the downstream substrates involved with the processing and secretion of the pro-inflammatory cytokines interleukin-1β (IL-1β) and IL-18 and tumor necrosis factor-α (TNF- α). The NLRP3 inflammasome is activated by a wide range of danger signals that derive from metabolic dysregulation. Activation of this complex often involves the adaptor ASC and upstream sensors including NLRP1, NLRP3, NLRC4, AIM2, and pyrin, which are activated by different stimuli including infectious agents and changes in cell homeostasis. It has been shown that nutraceuticals and medicinal plants have antiinflammatory properties and could be used as complementary therapy in the treatment of several chronic diseases that are related to inflammation, for example, cardiovascular diseases and diabetes mellitus. Herb-based medicine has demonstrated protective effects against NLRP3 inflammasome activation. Therefore, this review focuses on the effects of nutraceuticals and bioactive compounds derived from medicinal plants on NLRP3 inflammasome activation and the possible mechanisms of action of these natural products. Thus, herb-based, natural products/compounds can be considered novel, practical, and accessible agents in chronic inflammatory diseases by inhibiting NLRP3 inflammasome activation.

Down-regulation of protease-activated receptor 2 ameliorated osteoarthritis in rats through regulation of MAPK/NF-κB signaling pathway in vivo and in vitro

Recently, protease-activated receptor 2 (PAR2) has been proved to be involved in the inflammatory response including osteoarthritis (OA). In the present study, we found that PAR2 antagonist could remarkably improve the pathological condition of OA rats in vivo. In addition, we also found that PAR2 antagonist could suppress the production of inflammatory factors (TNF-α and Cox-2), decrease the levels of MMP-1 and MMP-13, and restrain the levels of P62 proteins and aggravate the expression of LC3-II both in vivo and in vitro. Besides, in vitro, PAR2 antagonist could increase the proliferation and colony formation of chondrocytes induced with IL-1β. Moreover, PAR2 antagonist could decrease the expression of expressions of p-p38, p-IκBα and p-NF-κB in vitro. However, PAR2 agonist exhibited the opposite effects. Furthermore, SB203580, a p38 MAPK inhibitor, could remarkably promote the proliferation of chondrocytes induced with IL-1β, could alleviate the production of TNF-α and Cox-2, could down-regulate the protein expressions of MMP-1 and MMP-13, and could decrease the expression of P62 and increase the expressions of LC3-II of chondrocytes induced with IL-1β. Importantly, SB203580 could reverse the effects of PAR2 agonist on the functions of chondrocytes induced with IL-1β. Taken together, the present data suggest that down-regulation of PAR2 can ameliorate OA through inducing autophagy via regulation of MAPK/NF-κB signaling pathway in vivo and in vitro, and PAR2 can be considered as a potential candidate to treat OA.

Specific NLRP3 inflammasome inhibitors: promising therapeutic agents for inflammatory diseases

Innate immunity serves as a first line of defence against danger signals, invading pathogens and microbes. The inflammasomes, as pattern recognition receptors, sense these danger signals to initiate pro-inflammatory cascades. The nucleotide-binding domain leucine-rich repeat and pyrin domain containing receptor 3 (NLRP3) inflammasome is the most well characterised inflammasome, and its aberrant activation is implicated in many inflammatory diseases. In the past decade, targeting the NLRP3 inflammasome has become an emerging strategy for inflammatory diseases. To avoid off-target immunosuppressive effects, specific NLRP3 inhibitors have been developed and show promising therapeutic effects. This review discusses the therapeutic effects and clinical perspectives of specific NLRP3 inhibitors, as well as recent progress in the development of these inhibitors for the treatment of inflammatory diseases.

Exogenous sodium hydrosulfide protects against high glucose‑induced injury and inflammation in human umbilical vein endothelial cells by inhibiting necroptosis via the p38 MAPK signaling pathway

In recent years hydrogen sulfide (H2S) has demonstrated vasculoprotective effects against cell death, which suggests its promising therapeutic potential for numerous types of disease. Additionally, a protective effect of exogenous H2S in HG‑induced injuries in HUVECs was demonstrated, suggesting a potential protective effect for diabetic vascular complications. The present study aimed to investigate the mechanism accounting for the cytoprotective role of exogenous H2S against high glucose [HG (40 mM glucose)]‑induced injury and inflammation in human umbilical vein endothelial cells (HUVECs). HUVECs were exposed to HG for 24 h to establish an in vitro model of HG‑induced cytotoxicity. The cells were pretreated with sodium hydrosulfide (NaHS), a donor of H2S, or inhibitors of necroptosis and p38 MAPK prior to the exposure to HG. Cell viability, intracellular reactive oxygen species (ROS), mitochondrial membrane potential (MMP), IL‑1β, IL‑6, IL‑8, TNF‑α, phosphorylated‑(p)38 and receptor‑interacting protein 3 (RIP3) expression levels were detected using the indicated methods, including Cell Counting Kit 8, fluorescence detection, western blotting, immunofluorescence assay and ELISAs. The results demonstrated that necroptosis and the p38 MAPK signaling pathway mediated HG‑induced injury and inflammation. Notably, NaHS was discovered to significantly ameliorate p38 MAPK/necroptosis‑mediated injury and inflammation in response to HG, as evidenced by an increase in cell viability, a decrease in ROS generation and loss of MMP, as well as the reduction in the secretion of proinflammatory cytokines. In addition, the upregulated expression of RIP3 induced by HG was repressed by treatment with SB203580, while the HG‑induced upregulation of p‑p38 expression levels were significantly downregulated following the treatment of Nec‑1 and RIP3‑siRNA. In conclusion, the findings of the present study indicated that NaHS may protect HUVECs against HG‑induced injury and inflammation by inhibiting necroptosis via the p38 MAPK signaling pathway, which may represent a promising drug for the therapy of diabetic vascular complications.

Isoliquiritigenin prevents hyperglycemia-induced renal injuries by inhibiting inflammation and oxidative stress via SIRT1-dependent mechanism

Diabetic nephropathy (DN) as a global health concern is closely related to inflammation and oxidation. Isoliquiritigenin (ISL), a natural flavonoid compound, has been demonstrated to inhibit inflammation in macrophages. Herein, we investigated the effect of ISL in protecting against the injury in STZ-induced type 1 DN and in high glucose-induced NRK-52E cells. In this study, it was revealed that the administration of ISL not only ameliorated renal fibrosis and apoptosis, but also induced the deterioration of renal function in diabetic mice. Mediated by MAPKs and Nrf-2 signaling pathways, respectively, upstream inflammatory response and oxidative stress were neutralized by ISL in vitro and in vivo. Moreover, as further revealed by the results of molecular docking, sirtuin 1 (SIRT1) binds to ISL directly, and the involvement of SIRT1 in ISL-mediated renoprotective effects was confirmed by studies using in vitro models of SIRT1 overexpression and knockdown. In summary, by reducing inflammation and oxidative stress, ISL has a significant pharmacological effect on the deterioration of DN. The benefits of ISL are associated with the direct binding to SIRT1, the inhibition of MAPK activation, and the induction of Nrf-2 signaling, suggesting the potential of ISL for DN treatment.

Promote anti-inflammatory and angiogenesis using a hyaluronic acid-based hydrogel with miRNA-laden nanoparticles for chronic diabetic wound treatment

Chronic diabetic wound causes serious threat to human health due to its long inflammatory phase and the reduced vascularization. Herein, we develop a hydrogel system for the treatment of diabetic wound, which can short the inflammatory stage (through the use of ori) and promote the angiogenesis (through the addition of siRNA-29a gene). Based on the Schiff base bonds, the Gel/Alg@ori/HA-PEI@siRNA-29a hydrogel was prepared by mixing oxidized hydroxymethyl propyl cellulose (OHMPC), adipic dihydrazide-modified hyaluronic acid (HA-ADH), oridonin (ori) loaded alginate microspheres (Alg@ori) and siRNA-29a gene-loading hyaluronic acid-polyethyleneimine complex HA-PEI@siRNA-29a (HA-PEI@siRNA-29a) under physiological conditions, which had moderate mechanical strength, appropriate swelling property, impressive stability, and slow release ability of ori and siRNA-29a. Excellent biocompatibility of the prepared hydrogel was also confirmed by in vitro mouse fibroblasts L929 cells culture study. Moreover, in vivo experiments further demonstrated that the prepared Gel/Alg@ori/HA-PEI@siRNA-29a hydrogel not only significantly accelerated the diabetic wound healing, angiogenesis factors (α-SMA and CD31) production, but also inhibited pro-inflammatory factors (IL-6 and TNF-α). In summary, we believe that the prepared hydrogels exhibit great potential for the treatment of chronic diabetic wound.

Effect of Artemisia absinthium ethanolic extract on oxidative stress markers and the TLR4, S100A4, Bax and Bcl-2 genes expression in the kidney of STZ-induced diabetic rats

OBJECTIVES

The present study was conducted to examine antidiabetic effects of Artemisia absinthium ethanolic extract [A. absinthium] and to investigate its effects on oxidative stress markers and the expression of TLR4, S100A4, Bax and Bcl-2 genes in the kidney of STZ-induced diabetic rats.

METHODS

Thirty six rats (weight 200-250 g) were randomly divided into diabetes and control groups. Induction of diabetes was performed using STZ (55 mg/kg.bw). Biochemical parameters and oxidative stress markers (SOD and MDA) were measured using spectrophotometry after 60 days of treatment. The expression of TLR4, S100A4, Bax and Bcl-2 were analyzed by real-time PCR. One-way analysis of variance (ANOVA) and Bonferroni post hoc test were used to compare the data.

RESULTS

Diabetes significantly impairs the serum fasting blood glucose (FBG), lipid profile, urea, creatinine and albumin. At the end of treatment with A. absinthium extract, these parameters were close to the normal range. The results showed that the A. absinthium extract significantly decreased the kidney expression of TLR4, S100A4, Bax and increased the expression of Bcl-2 and improved oxidative stress markers (SOD and MDA) in the kidney tissues of treated rats. Also, all of these beneficial effects of the A. absinthium were dose-dependent.

CONCLUSIONS

The extract of A. absinthium possesses antidiabetic effects. A. absinthium decreased the expression of TLR4, S100A4, Bax and increased the expression of Bcl-2 and improved oxidative stress. Therefore, this herbal extract can be used as an adjuvant treatment for diabetic complications.

The rCC16 Protein Protects Against LPS-Induced Cell Apoptosis and Inflammatory Responses in Human Lung Pneumocytes

Objective

Our previous clinical study showed that low lung levels of CC16 strongly influence the occurrence and development of ARDS. The aim of the present study was to evaluate the therapeutic effect of rCC16 on LPS-induced inflammation in A549 cells and to determine its mechanism.

Methods

Cell apoptosis and inflammation was induced by LPS stimulation. The cytotoxic effect of rCC16 was evaluated using the MTT assay. Cytokine levels were determined using enzyme-linked immunosorbent assays. The molecular mechanism of rCC16 was investigated by analyzing relevant signaling pathways.

Results

The LPS treatment of A549 cells significantly decreased cell viability, increased the levels of the apoptotic proteins Bax, Bak and Cleaved Caspase-3, the secretion of inflammatory cytokines, and the expression levels of TLR4, p-NF/κB, MAPK proteins. While the levels of Bcl-2, p-AKT, p-mTOR, p-ERK1/2, NF/κB, p-AMPK, and p-p38 were significantly decreased in LPS-treated A549 cells. Our experimental results also confirmed that rCC16 inhibited LPS-induced apoptosis, promoted A549 cell proliferation by activating the PI3K/AKT/mTOR/ERK1/2 pathway, and inhibited the release of certain inflammatory factors, especially HMGB1, through dephosphorylation and inactivation of the TLR4/NF-κB/AMPK signaling pathways.

Conclusion

These results highlight the potential utility of CC16 as an important cytokine for the prevention or treatment of inflammation and show that CC16 may play an important role in the future clinical treatment of ARDS.

Oridonin and its derivatives for cancer treatment and overcoming therapeutic resistance

Cancer is one of the diseases with high morbidity and mortality on a global scale. Chemotherapy remains the primary treatment option for most cancer patients, including patients with progressive, metastatic, and recurrent diseases. To date, hundreds of chemotherapy drugs are used to treat various cancers, however, the anti-cancer efficacy and outcomes are largely hampered by chemotherapy-associated toxicity and acquired therapeutic resistance. The natural product (NP) oridonin has been extensively studied for its anti-cancer efficacy. More recently, oridonin has been shown to overcome drug resistance through multiple mechanisms, with yet-to-be-defined bona fide targets. Hundreds of oridonin derivative analogs (oridonalogs) have been synthesized and screened for improved potency, bioavailability, and other drug properties. Particularly, many of these oridonalogs have been tested against oridonin for tumor growth inhibition, potential for overcoming therapeutic resistance, and immunity modulation. This concise review seeks to summarize the advances in this field in light of identifying clinical-trial level drug candidates with the promise for treating progressive cancers and reversing chemoresistance.

The TLR4-MyD88-NF-κB pathway is involved in sIgA-mediated IgA nephropathy

Previous studies have shown that secretory IgA (sIgA) was critically involved in IgA nephropathy (IgAN) immune responses. Toll-like receptors (TLRs), especially TLR4 which participates in mucosal immunity, may be involved in the pathogenesis of IgAN. The purpose of this study was to investigate whether sIgA and TLR4 interact to mediate kidney damage in IgAN patients. IgAN patients with positive sIgA deposition in renal tissues were screened by immunofluorescence assay. Patient salivary sIgA (P-sIgA) was collected and purified by jacalin affinity chromatography. Salivary sIgA from healthy volunteers was used as a control (N-sIgA). Expression of TLR4, MyD88, NF-κB, TNF-α, IL-6, and MCP-1 were detected in the mesangial area of IgAN patients by immunohistochemistry, the expression levels in patients with positive sIgA deposition were higher than that with negative sIgA deposition. Human renal mesangial cells (HRMCs) were cultured in vitro, flow cytometry showed that P-sIgA bound HRMCs significantly better than N-sIgA. HRMCs were cultured in the presence of sIgA (400 μg/mL) for 24 h, compared with cells cultured with N-sIgA, HRMCs cultured in vitro with P-sIgA showed enhanced expression of TLR4, increased secretion of TNF-α, IL-6, and MCP-1, and increased expression of MyD88/NF-κB. TLR4 shRNA silencing and NF-κB inhibition both reduced the ability of HRMCs to synthesize TNF-α, IL-6, and MCP-1. Our results indicate that sIgA may induce high expression of TLR4 in HRMCs and further activate downstream signalling pathways, prompting HRMCs to secrete multiple cytokines and thereby mediating kidney damage in IgAN patients.

Exosomes from high glucose-treated macrophages activate macrophages andinduce inflammatory responses via NF-κB signaling pathway in vitro and in vivo

There is increasing evidence that macrophages play an important role in the development and pathogenesis of diabetic nephropathy (DN) by secreting inflammatory cytokines. Exosomes are a family of extracellular vesicles that are secreted from almost all types of cells and associated with cell-to-cell communications. In this article, we try to investigate whether high glucose (HG)-treated macrophages-derived exosomes could activate macrophages and induce inflammatory responses in vivo and in vitro. We incubated the exosomes from high glucose-treated Raw264.7 cells (HG-Exo) and Raw264.7 cells for 24 h. The expression levels of related inflammatory molecules and NF-κB p65 signaling pathway were identified, as well as the intracellular localization of NF-κB p65 was detected. In vivo, HG-Exo was injected into mice via tail vein and the related parameters of kidneys were detected. Compared with the exosomes from normal glucose-treated Raw264.7 cells (NG-Exo), HG-Exo contained higher concentrations of IL-1β and iNOS. HG-Exo-treated Raw264.7 cells secreted higher level of related inflammatory molecules and promoted NF-κB p65 signaling pathway expression. HG-Exo induced the production of intracellular iNOS and α-SMA. In the HG-Exo group, NF-κB p65 positive signals were mainly distributed in the nucleus area. HG-Exo treated mice kidneys displayed a significantly mesangial expansion and proliferation. NF-κB p65 protein expression levels in mice renal tissue treated with HG-Exo was significantly up-regulated. These findings suggest that high glucose treated macrophages-derived exosomes may activate macrophages and accelerate kidney injury via NF-κB p65 signaling pathway.

Oridonin Alleviates IRI-Induced Kidney Injury by Inhibiting Inflammatory Response of Macrophages via AKT-Related Pathways

BACKGROUND Acute kidney injury (AKI) is one of the most common complications in clinic, but there is still no effective treatment. Oridonin, extracted from Rabdosia rubescens, has been identified to promote inhibitory effects on tumor, inflammatory and fibrosis by previous study. This study aimed to assess the kidney-protective role of Oridonin in AKI and the underlying mechanism by which Oridonin improves AKI in vivo and inhibits inflammation in LPS-induced bone marrow-derived macrophages (BMDM) in vitro. MATERIAL AND METHODS SPF C57BL/6J male mice (8 - 10 weeks old, body weight 20 - 25 g) were divided into 3 groups - sham group, AKI group, and Oridonin-treated AKI group - with 6 mice in each group. In the in vitro study, LPS-induced inflammatory BMDM cells were treated with Oridonin and agonist of AKT. The expression and secretion levels of inflammation-related indicators and AKT-related signaling molecules were detected by real-time PCR, ELISA, Western blot, and immunofluorescence. Also, various methods are used to assess renal function and pathological changes. RESULTS The results showed that Oridonin treatment significantly improved the serum creatinine and BUN levels in AKI mice. Interestingly, treatment with Oridonin also resulted in decreased the infiltration of macrophages in renal tissues of AKI mice, which was associated with decreased expression and activation of AKT and its related signaling pathways, such as NF-kappaB and STAT3, suggesting that Oridonin attenuates AKI kidney injury via a mechanism associated with reducing the inflammatory response of macrophages in the AKI kidney. This was investigated in vitro in macrophages, and the results showed that Oridonin reduced the LPS-stimulated inflammatory response in macrophages. Mechanistically, the addition of Oridonin reversed LPS-induced downregulation of AKT, NF-kappaB, and STAT3 expression and inflammatory response in macrophages, suggesting that Oridonin has a protective role, via the AKT-related signaling pathways, in reducing the inflammatory response of macrophages in AKI mice. This was further confirmed by adding agonist of AKT of IGF-1 to block the inhibitory effect of Oridonin on inflammatory response in vitro. CONCLUSIONS Oridonin ameliorates AKI kidney injuries by suppressing AKT-mediated inflammatory response of macrophages.

Glycyrrhizin Inhibits PEDV Infection and Proinflammatory Cytokine Secretion via the HMGB1/TLR4-MAPK p38 Pathway

Our previous study showed that glycyrrhizin (GLY) inhibited porcine epidemic diarrhea virus (PEDV) infection, but the mechanisms of GLY anti-PEDV action remain unclear. In this study, we focused on the anti-PEDV and anti-proinflammatory cytokine secretion mechanisms of GLY. We found that PEDV infection had no effect on toll-like receptor 4 (TLR4) protein and mRNA levels, but that TLR4 regulated PEDV infection and the mRNA levels of proinflammatory cytokines. In addition, we demonstrated that TLR4 regulated p38 phosphorylation but not extracellular regulated protein kinases1/2 (Erk1/2) and c-Jun N-terminal kinases (JNK) phosphorylation, and that GLY inhibited p38 phosphorylation but not Erk1/2 and JNK phosphorylation. Therefore, we further explored the relationship between high mobility group box-1 (HMGB1) and p38. We demonstrated that inhibition of HMGB1 using an antibody, mutation, or knockdown decreased p38 phosphorylation. Thus, HMGB1 participated in activation of p38 through TLR4. Collectively, our data indicated that GLY inhibited PEDV infection and decreased proinflammatory cytokine secretion via the HMGB1/TLR4-mitogen-activated protein kinase (MAPK) p38 pathway.

Oridonin Attenuates Lipopolysaccharide-Induced ROS Accumulation and Inflammation in HK-2 Cells

Renal tubulointerstitial inflammation plays an important role in chronic kidney disease (CKD). Inflammation reduction is a good strategy to combat CKD. Oridonin, an ent-kaurane diterpenoid isolated from Rabdosia rubescens (Donglingcao), is considered as an effective natural candidate for the treatment of anti-inflammatory, antiviral, and antibacterial activities, including liver fibrosis and many tumors; however, no study has demonstrated its effect on lipopolysaccharide- (LPS-) induced renal inflammation. To investigate the anti-inflammatory effects of oridonin on human renal proximal tubular epithelial cells (HK-2 cells), the expression levels of c-Jun N-terminal kinase (JNK) and reactive oxygen species (ROS) were evaluated by Western blot analysis and 2',7'-dichlorofluorescein diacetate (DCF-DA) staining, respectively. The level of intracellular ROS increased in a dose-dependent manner following LPS treatment, whereas oridonin inhibited this effect, suggestive of its ability to prevent ROS accumulation. As the mitogen-activated protein kinase (MAPK) family of enzymes plays an important role in physiological responses, we examined the activation of JNK by Western blotting and found that oridonin attenuated LPS-induced JNK phosphorylation. Oridonin also attenuated RAW 264.7 cell chemotaxis towards LPS-treated HK-2 cells. Taken together, oridonin protected against LPS-induced inflammation including ROS accumulation, JNK activation, NF-κB nuclear translocation in HK-2 cells, and functionally blocked macrophage chemotaxis towards LPS-treated HK-2 cells. Oridonin may exhibit therapeutic potential by the anti-inflammation effect in LPS-treated HK-2 cells.

Deltonin Ameliorates Cerebral Ischemia/Reperfusion Injury in Correlation with Modulation of Autophagy and Inflammation

INTRODUCTION

Deltonin, an active component extracted from Dioscorea zingiberensis C.H. WRIGHT, was widely utilized in traditional Chinese medicines. It has been shown to have anti-cancer functions such as colon cancer, breast cancer, and head and neck squamous carcinoma. Herein, we will investigate the role of deltonin in cerebral ischemia/reperfusion injuries.

METHODS

Ly294002 and anisomycin were used as inhibitors to monitor the effects of deltonin. Middle cerebral artery occlusion I/R model was constructed. Infarct volumes, neurological deficits and brain water contents were evaluated under different conditions. Rotarod test, ELISA, and Western blotting were carried to investigate the effects in vitro.

RESULTS

We found that deltonin in ischemia/reperfusion (I/R) rats greatly enhanced brain damages as well as neurological functions through up-regulating p-Akt and p-mTOR as well as inhibiting the expressions of LC3-II/LC3-I, Beclin-1, IL-1, TLR4, and p-p38. Deltonin exerted neuroprotection effect through relieving autophagy activity by regulating PI3K/Akt/mTOR signaling. Deltonin suppressed inflammation reactions through modulation TLR4/p38/MAPK signaling as well.

CONCLUSION

Overall, our data suggested that deltonin could suppress ischemic brain injury by regulating autophagy and inflammation during I/R. Deltonin can be a potential therapeutic method for patient with I/R.

Oridonin prevents insulin resistance-mediated cognitive disorder through PTEN/Akt pathway and autophagy in minimal hepatic encephalopathy

Minimal hepatic encephalopathy (MHE) was characterized for cognitive dysfunction. Insulin resistance (IR) has been identified to be correlated with the pathogenesis of MHE. Oridonin (Ori) is an active terpenoid, which has been reported to rescue synaptic loss and restore insulin sensitivity. In this study, we found that intraperitoneal injection of Ori rescued IR, reduced the autophagosome formation and synaptic loss and improved cognitive dysfunction in MHE rats. Moreover, in insulin‐resistant PC12 cells and N2a cells, we found that Ori blocked IR‐induced synaptic deficits via the down‐regulation of PTEN, the phosphorylation of Akt and the inhibition of autophagy. Taken together, these results suggested that Ori displays therapeutic efficacy towards memory deficits via improvement of IR in MHE and represents a novel bioactive therapeutic agent for treating MHE.

Myricetin relieves LPS-induced mastitis by inhibiting inflammatory response and repairing the blood-milk barrier

Mastitis, an inflammation of mammary gland, is a serious disease that affects the health of dairy cows around the world. Myricetin, a flavonoid from Bayberry, has been reported to suppress various inflammatory response. The aim of this study was to evaluate the effect of myricetin on lipopolysaccharide (LPS)-induced in vivo and in vitro mastitis model and clarify the underlying mechanism. In vivo experiments, myricetin attenuated the severity of inflammatory lesion and neutrophil infiltration. Moreover, myricetin pretreatment induced a significant decrease in the activity of myeloperoxidase (MPO) and the production of TNF-α, IL-6, and IL-1β triggered by LPS. Myricetin pretreatment could also increase the integrity of the blood-milk barrier and upregulate the tight junction proteins in LPS-induced mice mastitis. In vitro, myricetin inhibited LPS-induced inflammatory response in mice mammary epithelial cells (mMECs). In the further mechanism studies, we found that the anti-inflammatory effect of myricetin was mediated by inhibiting LPS-induced phosphorylation of AKT, IKK-α, IκB-α, and P65 in vivo and in vitro. Collectively, these data suggested that myricetin effectively ameliorated the inflammatory response by inhibiting the AKT/IKK/NF-κB signaling pathway and repairing the integrity of blood-milk barrier in LPS-induced mice mastitis.