Kaempferol attenuates diabetic nephropathy by inhibiting RhoA/Rho-kinase mediated inflammatory signalling

Chaihuang Yishen Granule ameliorates mitochondrial homeostasis by upregulating PRDX5/TFAM axis to inhibit renal fibrosis in CKD

BACKGROUND

Chaihuang Yishen Granules (CHYS) has been clinically proven to be effective for the treatment of chronic kidney disease (CKD), yet its underlying molecular mechanisms remain largely unexplored.

OBJECTIVE

To explore the innovative mechanisms by which CHYS alleviates CKD, focusing on its role in modulating PRDX5/TFAM-mediated mitochondrial homeostasis in renal cells.

METHODS

In this study, CKD mouse model was established by unilateral ureteral obstruction (UUO) and adenine (Ade) diet. Treatment interventions were administered by gavage with CHYS at doses of 3.8g/kg (low dose) and 7.6g/kg (high dose). The ameliorative effects of CHYS on CKD were evaluated by changes in renal function, kidney tissue structure, renal fibrosis, and mitochondrial dysfunction markers. Tert‑butyl hydroperoxide (t-BHP)-induced oxidative stress in TCMK1 cells was used to simulate CKD renal fibrosis induced by mitochondrial dysfunction in vitro.

RESULTS

CHYS significantly improves renal function and mitigates fibrosis while restoring mitochondrial homeostasis. Notably, PRDX5 expression, which is markedly reduced in CKD patients and mouse models, is substantially upregulated following CHYS treatment. Meanwhile, we demonstrate that ultrasound microbubble-mediated in situ overexpression of PRDX5 confers considerable renal protection in the UUO model. In vitro data show that CHYS effectively prevents t-BHP-induced mtDNA leakage in renal tubular cells, preserving mitochondrial function and stability, an effect compromised by PRDX5 knockdown. Moreover, our protein binding assays uncover a previously unreported interaction between PRDX5 and TFAM, with TFAM knockdown reversing the mitochondrial functional and fibrotic improvements achieved through PRDX5 overexpression and CHYS intervention.

CONCLUSION

These findings introduce a pioneering perspective on CHYS's mechanism of action. CHYS enhance TFAM activation through PRDX5 upregulation, counteract ROS-induced mitochondrial damage, and restoring mitochondrial homeostasis, and alleviates the progression of renal fibrosis in CKD, highlighting the innovative therapeutic potential of CHYS in mitochondrial-related renal pathologies.

Natural Compounds in Kidney Disease: Therapeutic Potential and Drug Development

Diabetic kidney disease (DKD) poses a major global health challenge, affecting millions of individuals and contributing to substantial morbidity and mortality. Traditional treatments have focused primarily on managing symptoms and slowing disease progression rather than reversing or halting kidney damage. However, recent advancements in natural compound research have unveiled promising new avenues for therapeutic development. Extensive research has been conducted to showcase the antioxidant advantages for kidney health, supporting the potential effectiveness of natural and synthetic products in clinical and experimental research. Bioactive substances found in large quantities in food, such as polyphenols, have emerged as adjuvants. This review manuscript aims to provide a comprehensive overview of natural compounds and their potential efficacy, mechanisms of action, and clinical applications in the prevention and treatment of various kidney diseases. This review emphasizes the connection between oxidative stress and inflammation in diabetic nephropathy (DN), which leads to harmful effects on kidney cells due to pathological damage. A lower incidence of DM2-related problems and a slower progression of end-stage renal disease have been associated with the consumption of these compounds.

Advance Glycation End Products Inhibition by Citrus paradisi Peel Extract; Characterization, LCMS-QTOF Analysis, and Biological Evaluation

Advance glycation end products (AGEs) are the main reason for diabetic complications. Persistent hyperglycemia and non-enzymatic glycation increase the rate of AGEs formation. Natural functional food-based approaches are mainly under investigation these days to discover new treatment options. We focused to investigate potential of medium polar fractions of Citrus paradesi. The peels fractions were analsyed for phytochemical profile, FTIR, HPLC-DAD, and LCMS-QTof, and biological investigation including antioxidant assays, α-glucosidase inhibition, and Anti AGEs inhibition was performed. LCMS-QTof confirmed the presence of flavonoids and polymethoxylated flavonoids including naringin, narirutin 4-O-glucoside, hesperidin, naringenin-7-O-rutinoside hexamethoxyflavone, 3,5,6,7,8,3',4' heptamethoxyflavone were major compounds. A significant antioxidant activity was recorded in case of chloroform fraction compared to ethyl acetate fraction. Similarly a substancial AGEs inhibition in oxidative mode (IC50 0.23 mg/mL) and non-oxidative mode (IC50 0.10 mg/mL) was observed in chloroform fraction, whereas ethyl acetate fraction was only active in oxidative mode (IC50 0.69 mg/mL). A moderate α-glucosidase inhibition (IC50 1.23 mg/mL) was noticed in total extract, while significant activity was recorded in chloroform fraction (IC50 0.78 mg/mL). It was concluded that medium polar fraction of C. paradesi possesses antidiabetic and anti-AGEs potential that can be due to presence of flavonoids and polymethoxylated flavonoids.

Suppression of ferroptosis through the SLC7A11/glutathione/glutathione peroxidase 4 axis contributes to the therapeutic action of the Tangshenning formula on diabetic renal tubular injury

BACKGROUND

Tangshenning (TSN) is a safe and effective formula to treat diabetic nephropathy (DN), and clinical studies have demonstrated that its therapeutic effects are related to oxidative stress improvements in patients. Herein, this study aims to explore the potential mechanism of how TSN alleviates diabetic renal tubular injury.

METHODS

The ultrahigh pressure liquid chromatography-quadrupole-time of flight mass spectrometry (UPLC-QTOF/MS) was used to identify the chemical composition and serum components of TSN. KK-Ay mice served to investigate the protective effects and regulatory mechanisms of TSN on tubular damage in DN. Furthermore, inhibitors and inducers of ferroptosis were employed in high glucose-cultured tubular epithelial cells (TECs) to verify the potential mechanisms of TSN. The expressions of proteins related to renal tubular injury, ferroptosis and solute carrier family 7, member 11 (SLC7A11)/glutathione (GSH)/glutathione peroxidase 4 (GPX4) axis were analyzed by western blot and immunofluorescence. Mitochondrial ultrastructure was observed in kidney tissues and TECs by a transmission electron microscope. Pathological changes in the renal tissues were observed by HE, PAS, and Prussian blue staining. Ferroptosis-related reactive oxygen species (ROS), malondialdehyde (MDA), ferrous ion, the intake of cystine, GSH, and oxidized glutathione (GSSG) were evaluated and contrasted in vivo or in vitro.

RESULTS

51 compounds of TSN powder and 11 components in TSN-containing serum were identified by UPLC-QTOF/MS method. Administration of TSN ameliorated the elevated levels of proteinuria, serum creatinine, blood urea nitrogen, abnormal expression of renal tubular injury markers, and pathological damage to the renal tubules in DN mice model. Intriguingly, a strong inhibition of ferroptosis after TSN treatment occurred in both DN mice model and high glucose-cultured TECs. Notably, induction of ferroptosis by erastin attenuated the protective effect of TSN in high glucose-cultured TECs, while the ferroptosis inhibition by ferrostatin-1 treatment protected renal tubular, which was similar to TSN, suggesting the contribution of TSN-mediated by the inhibition of ferroptosis in DN progression. Mechanistically, TSN upregulated the SLC7A11/GSH/GPX4 axis to inhibit ferroptosis.

CONCLUSION

TSN may delay the DN progression and attenuate the renal tubular injury by inhibiting the ferroptosis regulated by the SLC7A11/GSH/GPX4 axis.

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.

Potential Nephroprotective Effect of Kaempferol: Biosynthesis, Mechanisms of Action, and Clinical Prospects

Kidney is an essential organ that is highly susceptible to cellular injury caused by various toxic substances in the blood. Several studies have shown that untreated injuries to this organ can cause glomerulosclerosis, tubulointerstitial fibrosis, and tubular cell apoptosis, leading to kidney failure. Despite significant advancements in modern treatment, there is no fully effective drug for repairing its function, providing complete protection, and assisting in cell regeneration. Furthermore, some available medications have been reported to exacerbate injuries, showing the need to explore alternative treatments. Natural drugs are currently being explored as a new therapeutic strategy for managing kidney diseases. Kaempferol, a polyphenol found in plants, including vegetables, legumes, and fruits, has been extensively studied in various nephrotoxicity protocols. The compound has been reported to have potential as a nephroprotective agent with beneficial effects on various physiological pathways, such as CPL-induced kidney injury, DOX, LPO, ROS, RCC, and diabetic nephropathy. Therefore, this study aims to provide a brief overview of the current nephroprotective effects of kaempferol, as well as its molecular mechanisms of action, biosynthesis pathways, and clinical prospects.

Fecal Microbiota Transplantation-Mediated Rebalancing of the Gut-Brain Axis Alleviates Cisplatin-Induced Neuropathic Pain

Chemotherapy-induced neuropathic pain (CINP) presents a significant challenge in cancer treatment, necessitating novel therapeutic approaches. The intricate relationship between CINP and the gut-brain axis indicates a crucial role for the gut microbiota in pain modulation during cancer therapy. In this study, we investigated the effect of gut microbiota and their modulation on CINP in rats. Cisplatin administration (20 mg/kg, ip) disrupted the integrity of the blood-spinal cord barrier, as evidenced by reduced expression of tight junction proteins occludin and claudin-5 and increased leakage of pro-inflammatory cytokines into the spinal cord. Fecal microbiota transplantation (FMT, 0.5 mL of P.O.) from healthy rats over 21 days restored barrier integrity, as confirmed by Evan's blue assay. FMT intervention halted the progression of cisplatin-induced pain, demonstrated through a battery of pain assays assessing mechanical, thermal, and cold allodynia alongside hyperalgesia measurements. Additionally, FMT treatment reduced oxidative stress and modulated neuro-inflammatory markers, resulting in a rebalanced cytokine profile with decreased levels of neuro-inflammatory cytokines (IL-6 and TNFα) and increased expression of the anti-inflammatory cytokine IL-10. Gut microbiota-mediated IL-1β/NF-κB signaling emerged as a critical factor in leukocyte recruitment and microglial activation, highlighting the gut-brain axis as a key regulatory nexus in managing cisplatin-induced neuropathic pain. These findings underscore the therapeutic potential of targeting gut microbiota modulation as a promising strategy for alleviating CINP and improving the well-being of cancer patients undergoing chemotherapy.

Radix Astragali and Its Representative Extracts for Diabetic Nephropathy: Efficacy and Molecular Mechanism

Diabetic nephropathy (DN) is a common microvascular complication of diabetes mellitus (DM). Radix Astragali (RA), a frequently used Chinese herbal medicine in the Leguminosae family, Astragalus genus, with its extracts, has been proven to be effective in DN treatment both in clinical practice and experimental studies. RA and its extracts can reduce proteinuria and improve renal function. They can improve histopathology changes including thickening of the glomerular basement membrane, mesangial cell proliferation, and injury of endothelial cells, podocytes, and renal tubule cells. The mechanisms mainly benefited from antioxidative stress which involves Nrf2/ARE signaling and the PPARγ-Klotho-FoxO1 axis; antiendoplasmic reticulum stress which involves PERK-ATF4-CHOP, PERK/eIF2α, and IRE1/XBP1 pathways; regulating autophagy which involves SIRT1/NF-κB signaling and AMPK signaling; anti-inflammation which involves IL33/ST2 and NF-κB signaling; and antifibrosis which involves TGF-β1/Smads, MAPK (ERK), p38/MAPK, JNK/MAPK, Wnt/β-catenin, and PI3K/AKT/mTOR signaling pathways. This review focuses on the clinical efficacy and the pharmacological mechanism of RA and its representative extracts on DN, and we further document the traditional uses of RA and probe into the TCM theoretical basis for its application in DN.

Daphnetin modulates GLP-1R to alleviate cognitive dysfunction in diabetes: implications for inflammation and oxidative stress

Daphnetin exerts certain pharmacological function on a variety of diseases, but its role in diabetic cognitive dysfunction has not been elucidated. In this study, we carried a series of pharmacological studies of GLP-1R with daphnetin. In rats and PC12 cells, we found that daphnetin could alleviate diabetic cognitive dysfunction and increase the expression level of GLP-1R. Additionally, the anti-diabetic cognitive dysfunction effect of DAP was accompanied by the inhibition of inflammation and oxidative stress. Further in-depth studies demonstrated that the inhibition GLP-1R enhanced the protective effect of daphnetin, whilst, the overexpression of GLP-1R weakened the protective effect of daphnetin. These results indicated that daphnetin protects diabetes cognitive dysfunction by regulating GLP-1R-mediated inflammation and oxidative stress, act as a GLP-1R agonist. The study further demonstrated that daphnetin has great value in preventing cognitive dysfunction in type 2 diabetes, and GLP-1R is a key potential target for the treatment of related diseases.

Advances in relieving exercise fatigue for curcumin: Molecular targets, bioavailability, and potential mechanism

Intense and prolonged physical activity can lead to a decrease in muscle capacity, making it difficult to maintain the desired exercise intensity and resulting in exercise fatigue. The long-term effects of exercise fatigue can be very damaging to the body, so it is an urgent problem to be addressed. The intervention of foodborne active substances will be an effective measure. There is growing evidence that the molecular structure and function of curcumin have a positive effect on relieving fatigue. In this review, we summarize curcumin's molecular structure, which enables it to bind to a wealth of molecular targets, regulate signaling pathways, and thus alleviate exercise fatigue through a variety of mechanisms, including reducing oxidative stress, inhibiting inflammation, reducing metabolite accumulation, and regulating energy metabolism. The effects of curcumin on fatigue-related markers were analyzed from the perspective of animal models and human models and based on the bidirectional interaction between curcumin and intestinal microbiota: Intestinal microbiota can transform curcumin, and curcumin regulates gut microbiota through metabolic pathways, providing a new perspective for alleviating fatigue. This review contributes to a more comprehensive understanding of the possible molecular mechanisms of curcumin in anti-fatigue and provides a new possibility for the development of functional foods in the future.

Cyproheptadine, a SET7/9 inhibitor, reduces hyperglycaemia-induced ER stress alleviating inflammation and fibrosis in renal tubular epithelial cells

CONTEXT

Persistent hyperglycaemia increases SET7/9 expression and endoplasmic reticulum (ER) stress which causes inflammation, apoptosis, and fibrosis in renal tubular epithelial cells leading to diabetic kidney disease (DKD).

OBJECTIVE

Current study explores the renoprotective potential of a novel SET7/9 inhibitor, Cyproheptadine, and the underlying molecular mechanisms in hyperglycaemia-induced renal tubular epithelial cell injury.

METHODS

Change in expression of SET7/9, histone H3 lysine (K4) monomethylation (H3K4Me1), inflammatory, fibrotic, and ER stress proteins were evaluated in-vivo and in-vitro. NRK-52E cells were used to study the preventive effect of Cyproheptadine against hyperglycaemia-induced ER stress and subsequent inflammation and fibrosis.

RESULTS

SET7/9 and H3K4Me1 expression significantly increased with ER stress, inflammation, apoptosis, and fibrosis, in-vivo and in-vitro under hyperglycaemia. However, the cells treated with Cyproheptadine showed significant suppression of H3K4Me1 and reduction in ER stress, inflammation, apoptosis, and fibrosis.

CONCLUSION

Cyproheptadine prevented hyperglycaemia-induced renal fibrosis and inflammation by reducing H3K4Me1 expression and ER stress.

Dermorphin [D-Arg2, Lys4] (1-4) Amide Alleviates Frostbite-Induced Pain by Regulating TRP Channel-Mediated Microglial Activation and Neuroinflammation

Cold injury or frostbite is a common medical condition that causes serious clinical complications including sensory abnormalities and chronic pain ultimately affecting overall well-being. Opioids are the first-choice drug for the treatment of frostbite-induced chronic pain; however, their notable side effects, including sedation, motor incoordination, respiratory depression, and drug addiction, present substantial obstacle to their clinical utility. To address this challenge, we have exploited peripheral mu-opioid receptors as potential target for the treatment of frostbite-induced chronic pain. In this study, we investigated the effect of dermorphin [D-Arg2, Lys4] (1-4) amide (DALDA), a peripheral mu-opioid receptor agonist, on frostbite injury and hypersensitivity induced by deep freeze magnet exposure in rats. Animals with frostbite injury displayed significant hypersensitivity to mechanical, thermal, and cold stimuli which was significant ameliorated on treatment with different doses of DALDA (1, 3, and 10 mg/kg) and ibuprofen (100 mg/kg). Further, molecular biology investigations unveiled heightened oxido-nitrosative stress, coupled with a notable upregulation in the expression of TRP channels (TRPA1, TRPV1, and TRPM8), glial cell activation, and neuroinflammation (TNF-α, IL-1β) in the sciatic nerve, dorsal root ganglion (DRG), and spinal cord of frostbite-injured rats. Treatment with DALDA leads to substantial reduction in TRP channels, microglial activation, and suppression of the inflammatory cascade in the ipsilateral L4-L5 DRG and spinal cord of rats. Overall, findings from the present study suggest that activation of peripheral mu-opioid receptors mitigates chronic pain in rats by modulating the expression of TRP channels and suppressing glial cell activation and neuroinflammation.

Alpha-cyperone mitigates renal ischemic injury via modulation of HDAC-2 expression in diabetes: Insights from molecular dynamics simulations and experimental evaluation

Chronic diabetes mellitus is reported to be associated with acute kidney injury. The enzyme histone deacetylase-2 (HDAC-2) was found to be upregulated in diabetes-related kidney damage. Alpha-cyperone (α-CYP) is one of the active ingredients of Cyperus rotundus that possesses antioxidant and anti-inflammatory effects. We evaluated the effect of α-CYP on improving oxidative stress and tissue inflammation following renal ischemia/reperfusion (I/R) injury in diabetic rats. The effect of α-CYP on HDAC-2 expression in renal homogenates and in the NRK-52 E cell line was evaluated following renal I/R injury and high glucose conditions, respectively. Molecular docking was used to investigate the binding of α-CYP with the HDAC-2 active site. Both renal function and oxidative stress were shown to be impaired in diabetic rats due to renal I/R injury. Significant improvements in kidney/body weight ratio, creatinine clearance, serum creatinine, blood urea nitrogen (BUN), and uric acid were observed in diabetic rats treated with α-CYP (50 mg/kg) two weeks prior to renal I/R injury. α-CYP treatment also improved histological alterations in renal tissue and lowered levels of malondialdehyde, myeloperoxidase, and hydroxyproline. Treatment with α-CYP suppressed the increased HDAC-2 expression in the renal tissue of diabetic rats and in the NRK-52 E cell line. The molecular docking reveals that α-CYP binds to HDAC-2 with good affinity, ascertained by molecular dynamics simulations and binding free energy analysis. Overall, our data suggest that α-CYP can effectively prevent renal injury in diabetic rats by regulating oxidative stress, tissue inflammation, fibrosis and inhibiting HDAC-2 activity.

Molecular mechanisms and therapeutic potential of natural flavonoids in diabetic nephropathy: Modulation of intracellular developmental signaling pathways

Recognized as a common microvascular complication of diabetes mellitus (DM), diabetic nephropathy (DN) is the principal cause of chronic end-stage renal disease (ESRD). Patients with diabetes have an approximately 25% risk of developing progressive renal disease. The underlying principles of DN control targets the dual outcomes of blood glucose regulation through sodium glucose cotransporter 2 (SGLT 2) blockade and hypertension management through renin-angiotensin-aldosterone inhibition. However, these treatments are ineffective in halting disease progression to kidney failure and cardiovascular comorbidities. Recently, the dysregulation of subcellular signaling pathways has been increasingly implicated in DN pathogenesis. Natural compounds are emerging as effective and side-effect-free therapeutic agents that target intracellular pathways. This narrative review synthesizes recent insights into the dysregulation of maintenance pathways in DN, drawing from animal and human studies. To compile this review, articles reporting DN signaling pathways and their treatment with natural flavonoids were collected from PubMed, Cochrane Library Web of Science, Google Scholar and EMBASE databases since 2000. As therapeutic interventions are frequently based on the results of clinical trials, a brief analysis of data from current phase II and III clinical trials on DN is discussed.

Kaempferol efficacy in metabolic diseases: Molecular mechanisms of action in diabetes mellitus, obesity, non-alcoholic fatty liver disease, steatohepatitis, and atherosclerosis

The incidence of metabolic diseases has progressively increased, which has a negative impact on human health and life safety globally. Due to the good efficacy and limited side effects, there is growing interest in developing effective drugs to treat metabolic diseases from natural compounds. Kaempferol (KMP), an important flavonoid, exists in many vegetables, fruits, and traditional medicinal plants. Recently, KMP has received widespread attention worldwide due to its good potential in the treatment of metabolic diseases. To promote the basic research and clinical application of KMP, this review provides a timely and comprehensive summary of the pharmacological advances of KMP in the treatment of four metabolic diseases and its potential molecular mechanisms of action, including diabetes mellitus, obesity, non-alcoholic fatty liver disease (NAFLD)/nonalcoholic steatohepatitis (NASH), and atherosclerosis. According to the research, KMP shows remarkable therapeutic effects on metabolic diseases by regulating multiple signaling transduction pathways such as NF-κB, Nrf2, AMPK, PI3K/AKT, TLR4, and ER stress. In addition, the most recent literature on KMP's natural source, pharmacokinetics studies, as well as toxicity and safety are also discussed in this review, thus providing a foundation and evidence for further studies to develop novel and effective drugs from natural compounds. Collectively, our manuscript strongly suggested that KMP could be a promising candidate for the treatment of metabolic diseases.

Qi-dan-dihuang decoction ameliorates renal fibrosis in diabetic rats via p38MAPK/AKT/mTOR signaling pathway

CONTEXT

Qi-dan-dihuang decoction (QDD) has been used to treat diabetic kidney disease (DKD), but the underlying mechanisms are poorly understood.

OBJECTIVE

This study reveals the mechanism by which QDD ameliorates DKD.

MATERIALS AND METHODS

The compounds in QDD were identified by high-performance liquid chromatography and quadrupole-time-of-flight tandem mass spectrometry (HPLC-Q-TOF-MS). Key targets and signaling pathways were screened through bioinformatics. Nondiabetic Lepr db/m mice were used as control group, while Lepr db/db mice were divided into model group, dapagliflozin group, 1% QDD-low (QDD-L), and 2% QDD-high (QDD-H) group. After 12 weeks of administration, 24 h urinary protein, serum creatinine, and blood urea nitrogen levels were detected. Kidney tissues damage and fibrosis were evaluated by pathological staining. In addition, 30 mmol/L glucose-treated HK-2 and NRK-52E cells to induce DKD model. Cell activity and migration capacity as well as protein expression levels were evaluated.

RESULTS

A total of 46 key target genes were identified. Functional enrichment analyses showed that key target genes were significantly enriched in the phosphatidylinositol 3-kinase (PI3K)/protein kinase B (AKT) and mitogen-activated protein kinase (MAPK) signaling pathways. In addition, in vivo and in vitro experiments confirmed that QDD ameliorated renal fibrosis in diabetic mice by resolving inflammation and inhibiting the epithelial-mesenchymal transition (EMT) via the p38MAPK and AKT-mammalian target of rapamycin (mTOR) pathways.

DISCUSSION AND CONCLUSION

QDD inhibits EMT and the inflammatory response through the p38MAPK and AKT/mTOR signaling pathways, thereby playing a protective role in renal fibrosis in DKD.

Scopoletin alleviates high glucose-induced toxicity in human renal proximal tubular cells via inhibition of oxidative damage, epithelial-mesenchymal transition, and fibrogenesis

BACKGROUND

Recent years of evidence suggest the crucial role of renal tubular cells in developing diabetic kidney disease. Scopoletin (SCOP) is a plant-based coumarin with numerous biological activities. This study aimed to determine the effect of SCOP on renal tubular cells in developing diabetic kidney disease and to elucidate mechanisms.

METHODS AND RESULTS

In this study, SCOP was evaluated in vitro using renal proximal tubular (HK-2) cells under hyperglycemic conditions to understand its mechanism of action. In HK-2 cells, SCOP alleviated the high glucose-generated reactive oxygen species (ROS), restored the levels of reduced glutathione, and decreased lipid peroxidation. High glucose-induced alteration in the mitochondrial membrane potential was markedly restored in the SCOP-treated cells. Moreover, SCOP significantly reduced the high glucose-induced apoptotic cell population in the Annexin V-FITC flow cytometry study. Furthermore, high glucose markedly elevated the mRNA expression of fibrotic and extracellular matrix (ECM) components, namely, transforming growth factor (TGF)-β, alfa-smooth muscle actin (α-SMA), collagen I, and collagen III, in HK-2 cells compared to the untreated cells. SCOP treatment reduced these mRNA expressions compared to the high glucose-treated cells. Collagen I and TGF-β protein levels were also significantly reduced in the SCOP-treated cells. Further findings in HK-2 cells revealed that SCOP interfered with the epithelial-mesenchymal transition (EMT) in the high glucose-treated HK-2 cells by normalizing E-cadherin and downregulating the vimentin and α-SMA proteins.

CONCLUSIONS

In conclusion, SCOP modulates the high glucose-generated renal tubular cell oxidative damage and accumulation of ECM components and may be a promising molecule against diabetic nephropathy.

Pharmacological Potential of Kaempferol, a Flavonoid in the Management of Pathogenesis via Modulation of Inflammation and Other Biological Activities

Natural products and their bioactive compounds have been used for centuries to prevent and treat numerous diseases. Kaempferol, a flavonoid found in vegetables, fruits, and spices, is recognized for its various beneficial properties, including its antioxidant and anti-inflammatory potential. This molecule has been identified as a potential means of managing different pathogenesis due to its capability to manage various biological activities. Moreover, this compound has a wide range of health-promoting benefits, such as cardioprotective, neuroprotective, hepatoprotective, and anti-diabetic, and has a role in maintaining eye, skin, and respiratory system health. Furthermore, it can also inhibit tumor growth and modulate various cell-signaling pathways. In vivo and in vitro studies have demonstrated that this compound has been shown to increase efficacy when combined with other natural products or drugs. In addition, kaempferol-based nano-formulations are more effective than kaempferol treatment alone. This review aims to provide detailed information about the sources of this compound, its bioavailability, and its role in various pathogenesis. Although there is promising evidence for its ability to manage diseases, it is crucial to conduct further investigations to know its toxicity, safety aspects, and mechanism of action in health management.

Glucose regulation by newly synthesized boronic acid functionalized molecules as dipeptidyl peptidase IV inhibitor: a potential compound for therapeutic intervention in hyperglycaemia

Management of type 2 diabetes mellitus (T2DM) using dipeptidyl peptidase IV (DPP IV) inhibitors is gaining precedence as this enzyme plays an indispensable role in cleaving and inactivating peptides, such as glucagon-like peptide-1 (GLP-1), incretin hormones, and glucose-dependent insulinotropic polypeptide (GIP). There are several DPP IV inhibitors used to treat T2DM, but limited by side effects such as disturbed GIT, flu-like symptoms, etc. Thus, there is an urgent need for the development of novel and better DPP IV inhibitors for the management of the same. In the present study, we investigated the effect of new boronic acid-based thiazole compounds as DPP IV inhibitors. We used substituted anilines that were progressively modified through a multi-step synthesis and then chemically characterised. These molecules have good binding affinity and molecular interactions at the active site of the DPP IV enzyme. Two boronic acid-based molecules, i.e. PC06R58 and PC06R108, were used for the assessment of their in-vitro enzymatic activities. Both molecules (PC06108 and PC06R58) exhibited potent uncompetitive DPP IV enzyme inhibition at two different concentrations of 90.9 and 15.6 nM, respectively, compared to sitagliptin having an IC50 of 17.3 nM. Furthermore, the oral glucose tolerance test suggested significantly reduced blood glucose levels at 20 mg/kg of the body weight upon administration of PC06R58 and PC06R108 molecules in rats after glucose ingestion (2 g/kg of the body weight). The compounds showed satisfactory DPP IV inhibition. Furthermore, DPP IV inhibitory activity and acceptable pre-ADME/Tox profile indicate it is a lead compound in this novel class of DPP IV inhibitors.Communicated by Ramaswamy H. Sarma.

Kaempferol attenuates inflammation in lipopolysaccharide-induced gallbladder epithelial cells by inhibiting the MAPK/NF-κB signaling pathway

Kaempferol (KPR), a flavonoid compound found in various plants and foods, has garnered attention for its anti-inflammatory, antioxidant, and anticancer properties. In preliminary studies, KPR can modulate several signaling pathways involved in inflammation, making it a candidate for treating cholecystitis. This study aimed to explore the effects and mechanisms of KPR on lipopolysaccharide (LPS)-induced human gallbladder epithelial cells (HGBECs). To assess the impact of KPR on HGBECs, the HGBECs were divided into control, KPR, LPS, LPS + KPR, and LPS + UDCA groups. Cell viability and cytotoxicity were evaluated by MTT assay and lactate dehydrogenase (LDH) assay, respectively, and concentrations of KPR (10-200 μM) were tested. LPS-induced inflammatory responses in HGBECs were to create an in vitro model of cholecystitis. The key inflammatory markers (IL-1β, IL-6, and TNF-α) levels were quantified using ELISA, The modulation of the MAPK/NF-κB signaling pathway was measured by western blot using specific antibodies against pathway components (p-IκBα, IκBα, p-p65, p65, p-JNK, JNK, p-ERK, ERK, p-p38, and p38). The cell viability and LDH levels in HGBECs were not significantly affected by 50 μM KPR, thus it was selected as the optimal KPR intervention concentration. KPR increased the viability of LPS-induced HGBECs. Additionally, KPR inhibited the inflammatory factors level (IL-1β, IL-6, and TNF-α) and protein expression (iNOS and COX-2) in LPS-induced HGBECs. Furthermore, KPR reversed LPS-induced elevation of p-IκBα/IκBα, p-p65/p65, p-JNK/JNK, p-ERK/ERK, and p-p38/p38 ratios. KPR attenuates the LPS-induced inflammatory response in HGBECs, possibly by inhibiting MAPK/NF-κB signaling.

Integration of dietary nutrition and TRIB3 action into diabetes mellitus

Despite intensive studies for decades, the common mechanistic correlations among the underlying pathology of diabetes mellitus (DM), its complications, and effective clinical treatments remain poorly characterized. High-quality diets and nutrition therapy have played an indispensable role in the management of DM. More importantly, tribbles homolog 3 (TRIB3), a nutrient-sensing and glucose-responsive regulator, might be an important stress-regulatory switch, linking glucose homeostasis and insulin resistance. Therefore, this review aimed to introduce the latest research progress on the crosstalk between dietary nutrition intervention and TRIB3 in the development and treatment of DM. This study also summarized the possible mechanisms involved in the signaling pathways of TRIB3 action in DM, in order to gain an in-depth understanding of dietary nutrition intervention and TRIB3 in the pathogenesis of DM at the organism level.

Comprehensive Analysis of Fatty Acid Metabolism in Diabetic Nephropathy from the Perspective of Immune Landscapes, Diagnosis and Precise Therapy

Objective

Diabetic nephropathy (DN) represents the principal cause of end-stage renal diseases worldwide, lacking effective therapies. Fatty acid (FA) serves as the primary energy source in the kidney and its dysregulation is frequently observed in DN. Nevertheless, the roles of FA metabolism in the occurrence and progression of DN have not been fully elucidated.

Methods

Three DN datasets (GSE96804/GSE30528/GSE104948) were obtained and combined. Differentially expressed FA metabolism-related genes were identified and subjected to DN classification using "ConsensusClusterPlus". DN subtypes-associated modules were discovered by "WGCNA", and module genes underwent functional enrichment analysis. The immune landscapes and potential drugs were analyzed using "CIBERSORT" and "CMAP", respectively. Candidate diagnostic biomarkers of DN were screened using machine learning algorithms. A prediction model was constructed, and the performance was assessed using receiver operating characteristic (ROC) curves, calibration curves, and decision curve analysis (DCA). The online tool "Nephroseq v5" was conducted to reveal the clinical significance of the candidate diagnostic biomarkers in patients with DN. A DN mouse model was established to verify the biomarkers' expression.

Results

According to 39 dysregulated FA metabolism-related genes, DN samples were divided into two molecular subtypes. Patients in Cluster B exhibited worse outcomes with a different immune landscape compared with those in Cluster A. Ten potential small-molecular drugs were predicted to treat DN in Cluster B. The diagnostic model based on PRKAR2B/ANXA1 was created with ideal predictive values in early and advanced stages of DN. The correlation analysis revealed significant association between PRKAR2B/ANXA1 and clinical characteristics. The DN mouse model validated the expression patterns of PRKAR2B/ANXA1.

Conclusion

Our study provides new insights into the role of FA metabolism in the classification, immunological pathogenesis, early diagnosis, and precise therapy of DN.

Sida cordifolia L. attenuates behavioral hypersensitivity by interfering with KIF17-NR2B signaling in rat model of neuropathic pain

ETHNOPHARMACOLOGICAL RELEVANCE

Sida cordifolia L., a perennial subshrub belonging to the Malvaceae family, holds noteworthy significance in the Indian Ayurvedic System and global texts. Roots of this plant are reported to be useful in neurodegenerative disorders, facial paralysis, and treating several neuropathic pain conditions such as neuralgia, and sciatica. However, despite these claims, there remains a dearth of experimental evidence showcasing the effectiveness of Sida cordifolia L. roots in mitigating neuropathic pain.

AIM OF THE STUDY

The primary objective of this study was to assess the analgesic properties of the whole extract (SCE) obtained from the roots of Sida cordifolia L., as well as its aqueous fraction (SAF) in rat model of chronic constriction injury (CCI)-induced neuropathic pain. Furthermore, in-depth phytochemical and molecular biology studies were conducted to identify the potential phytoconstituents and unveil the underlying mechanisms of action.

MATERIAL AND METHODS

DCM: Methanol (1:1) was used to extract the roots of Sida cordifolia L. to get whole extract (SCE) and was subjected to phytochemical investigations including LC-MS analysis. Analgesic potential of SCE was evaluated in chronic constriction injury (CCI) model of neuropathic pain in rats followed by its bioactivity guided fractionation using in-vitro anti-inflammatory assay and assessment of most potent fraction (SAF) in in-vivo pain model. We have also performed the detailed phytochemical and molecular biology investigations to delineate the mechanism of action of Sida cordifolia root extract.

RESULTS

Chronic constriction injury leads to significant decrease in paw withdrawal threshold and paw withdrawal latency indicating development of hypersensitivity in rodents. Treatment with SCE and its most potent aqueous fraction (SAF) leads to significant and dose-dependent reduction in pain-like behavior of nerve injured rats. Pro-inflammatory cytokines (TNF-α, IL-1β), glia cell markers (Iba1, ICAM1), neuropeptides (CGRP and Substance P), KIF-17 and NR2B expressions were found to be significantly upregulated in DRG and spinal cord of nerve injured rats. Treatment with SCE and SAF suppressed oxido-inflammatory cascade along with attenuation of KIF-17 mediated NR2B trafficking and neuroinflammation in DRG and spinal tissues of neuropathic rats. HPTLC and HR-MS analysis suggest betaine as major constituent in SAF which along with other phytoconstituents.

CONCLUSIONS

Both the whole extract (SCE) and the aqueous fraction (SAF) demonstrate a significant reduction in mechanical and thermal hypersensitivity by inhibiting KIF-17 mediated NR2B signaling in nerve injured rats and may be used as a potential alternative for the treatment of chronic pain. Our findings support the use of roots of Sida cordifolia L. in neuropathic pain conditions as acclaimed by its traditional use.

The Anticancer Potential of Kaempferol: A Systematic Review Based on In Vitro Studies

Given the heterogeneity of different malignant processes, planning cancer treatment is challenging. According to recent studies, natural products are likely to be effective in cancer prevention and treatment. Among bioactive flavonoids found in fruits and vegetables, kaempferol (KMP) is known for its anti-inflammatory, antioxidant, and anticancer properties. This systematic review aims to highlight the potential therapeutic effects of KMP on different types of solid malignant tumors. This review was conducted following the Preferred Reporting Items for Systematic Review and Meta-Analyses (PRISMA) guidelines. Searches were performed in EMBASE, Medline/PubMed, Cochrane Collaboration Library, Science Direct, Scopus, and Google Scholar. After the application of study criteria, 64 studies were included. In vitro experiments demonstrated that KMP exerts antitumor effects by controlling tumor cell cycle progression, proliferation, apoptosis, migration, and invasion, as well as by inhibiting angiogenesis. KMP was also able to inhibit important markers that regulate epithelial-mesenchymal transition and enhanced the sensitivity of cancer cells to traditional drugs used in chemotherapy, including cisplatin and 5-fluorouracil. This flavonoid is a promising therapeutic compound and its combination with current anticancer agents, including targeted drugs, may potentially produce more effective and predictable results.

Peripheral mu-opioid receptor activation by dermorphin [D-Arg2, Lys4] (1-4) amide alleviates behavioral and neurobiological aberrations in rat model of chemotherapy-induced neuropathic pain

Paclitaxel, a frequently utilized chemotherapeutic agent, often gives rise to severe and distressing sensory neuropathy in patients undergoing chemotherapy. Unfortunately, current therapeutics for chemotherapy-induced neuropathic pain (CINP) demonstrate limited effectiveness and are burdened with the potential for central side effects such as sedation, respiratory depression, cognitive impairment, and addiction, posing substantial clinical challenges. In light of these limitations, present study is designed to investigate the therapeutic potential of Dermorphin [D-Arg2, Lys4] (1-4) amide (DALDA), a preferential peripherally acting mu-opioid receptor agonist, in rat model of CINP. The primary objective was to assess the analgesic properties of DALDA and elucidate the underlying mechanisms governing its therapeutic activity. Our findings revealed that DALDA treatment significantly ameliorated paclitaxel-induced evoked and spontaneous ongoing pain in rats without causing drug addiction and other central side effects. Molecular analyses further unveiled that paclitaxel administration resulted in increased expression of TRP channels, NR2B, voltage-gated sodium channels (VGSCs) and neuroinflammatory markers in both the dorsal root ganglion (DRG) and the spinal cord (L4-L5 region) of rats. DALDA treatment significantly downregulated ion channels (TRPs, VGSCs) and NR2B expressions, concomitant with the inhibition of microglial activation, resulting in the suppression of oxido-nitrosative stress and neuroinflammatory cascade. Findings from the current study suggests that peripheral mu-opioid receptors may offer a potential target for the treatment of patients suffering from CINP, offering new avenues for improved pain relief while minimizing central side effects.

Combination chemotherapy in rodents: a model for chemotherapy-induced neuropathic pain and pharmacological screening

Chemotherapy-induced neuropathic pain (CINP) remains a therapeutic challenge, with no US-FDA approved drugs or effective treatments available. Despite significant progress in unravelling the pathophysiology of CINP, the clinical translation of this knowledge into tangible outcome remains elusive. Here, we employed behavioural and pharmacological approaches to establish and validate a novel combination-based chemotherapeutic model of peripheral neuropathy. Male Sprague Dawley rats were subjected to chemotherapy administration followed by assessment of pain behaviour at different time-points post-chemotherapy. Paclitaxel-treated animals displayed an enhanced thermal and mechanical hypersensitivity from day four onwards which continued till day thirty-five post last paclitaxel injection. Notably, rats subjected to combination chemotherapy, displayed prolonged hypersensitivity that emerged on day four and persisted until day fifty-six. RT-PCR analysis revealed significant upregulation in DRG and spinal mRNA expressions of TRP channels (TRPA1, TRPV1, & TRPM8), pro-inflammatory cytokines (TNF-α & IL-1β) and neuropeptides, Substance P and CGRP in both the pain models. Interestingly, the combination chemotherapy model demonstrated a significant increase in DRG and spinal NR2B expressions compared to rats solely treated with paclitaxel. Pharmacological investigations revealed that gabapentin treatment substantially mitigates pain hypersensitivity in both the combined chemotherapy and paclitaxel-administered groups, with the simultaneous reversal of cellular and molecular changes observed in the lumbar DRG and spinal cord of rats. The findings from this study suggests that combination chemotherapy model exhibits heightened and prolonged hypersensitivity in comparison to the conventional paclitaxel-induced neuropathic pain model. This model not only recapitulates clinical biomarkers of neuropathy but also presents a potential alternative platform for screening analgesic drugs targeted at CINP.

Flavonoids, Isoflavonoids and others Bioactives for Insulin Sensitizations

Diabetes is a chronic condition that has an impact on a huge part of the world. Both animals and humans have been demonstrated to benefit from natural goods, and organisms (animals, or microbes). In 2021, approximately 537 million adults (20-79 years) are living with diabetes, making it the one of the biggest cause of death worldwide. Various phytoconstituent preserved β- cells activity helps to prevent the formation of diabetes problems. As a result, β-cells mass and function are key pharmaceutical targets. The purpose of this review is to provide an overview of flavonoids' effects on pancreatic β-cells. Flavonoids have been demonstrated to improve insulin release in cell lines of isolated pancreatic islets and diabetic animal models. Flavonoids are thought to protect β-cells by inhibiting nuclear factor-κB (NF-κB) signaling, activating the phosphatidylinositol 3-kinase (PI3K) pathway, inhibiting nitric oxide production, and lowering reactive oxygen species levels. Flavonoids boost β-cells secretory capacity by improving mitochondrial bioenergetic function and increasing insulin secretion pathways. Some of the bioactive phytoconstituents such as S-methyl cysteine sulfoxides stimulate insulin synthesis in the body and increase pancreatic output. The berberine increased insulin secretion in the HIT-T15 and Insulinoma 6 (MIN6) mouse cell line. Epigallocatechin-3-Gallate protects against toxicity accrued by cytokines, reactive oxygen species (ROS), and hyperglycemia. Quercetin has been proven to boost insulin production by Insulinoma 1 (INS-1) cells and also protect cell apoptosis. Overall flavonoids have beneficial effects on β-cells by prevented their malfunctioning or degradation and improving synthesis or release of insulin from β-cells.

Flavonols affect the interrelated glucosinolate and camalexin biosynthetic pathways in Arabidopsis thaliana

Flavonols are structurally and functionally diverse biomolecules involved in plant biotic and abiotic stress tolerance, pollen development, and inhibition of auxin transport. However, their effects on global gene expression and signaling pathways are unclear. To explore the roles of flavonol metabolites in signaling, we performed comparative transcriptome and targeted metabolite profiling of seedlings from the flavonol-deficient Arabidopsis loss-of-function mutant flavonol synthase1 (fls1) with and without exogenous supplementation of flavonol derivatives (kaempferol, quercetin, and rutin). RNA-seq results indicated that flavonols modulate various biological and metabolic pathways, with significant alterations in camalexin and aliphatic glucosinolate synthesis. Flavonols negatively regulated camalexin biosynthesis but appeared to promote the accumulation of aliphatic glucosinolates via transcription factor-mediated up-regulation of biosynthesis genes. Interestingly, upstream amino acid biosynthesis genes involved in methionine and tryptophan synthesis were altered under flavonol deficiency and exogenous supplementation. Quercetin treatment significantly up-regulated aliphatic glucosinolate biosynthesis genes compared with kaempferol and rutin. In addition, expression and metabolite analysis of the transparent testa7 mutant, which lacks hydroxylated flavonol derivatives, clarified the role of quercetin in the glucosinolate biosynthesis pathway. This study elucidates the molecular mechanisms by which flavonols interfere with signaling pathways, their molecular targets, and the multiple biological activities of flavonols in plants.

Signaling pathways regulated by natural active ingredients in the fight against exercise fatigue-a review

Exercise fatigue is a normal protective mechanism of the body. However, long-term fatigue hinders normal metabolism and exercise capacity. The generation and recovery from exercise fatigue involves alterations in multiple signaling pathways, mainly AMPK, PI3K/Akt, Nrf2/ARE, NF-κB, PINK1/Parkin, and BDNF/TrkB, as well as MAPK signaling pathways that mediate energy supply, reduction of metabolites, oxidative stress homeostasis, muscle fiber type switching, and central protective effects. In recent studies, a rich variety of natural active ingredients have been identified in traditional Chinese medicines and plant extracts with anti-fatigue effects, opening up the field of research in new anti-fatigue drugs. In this review we give an overview of the signaling pathways associated with the activity of natural food active ingredients against exercise fatigue. Such a comprehensive review is necessary to understand the potential of these materials as preventive measures and treatments of exercise fatigue. We expect the findings highlighted and discussed here will help guide the development of new health products and provide a theoretical and scientific basis for future research on exercise fatigue.

Urinary exosomes from patients with diabetic kidney disease induced podocyte apoptosis via microRNA-145-5p/Srgap2 and the RhoA/ROCK pathway

Diabetic kidney disease (DKD) is a leading cause of end-stage renal disease without early diagnostic and specific therapeutic approaches. Podocyte apoptosis and loss play important roles in the pathological process of DKD. This study aimed to explore whether urinary exosomes from type 2 diabetes patients with DKD could induce podocyte apoptosis and the underlying pathological mechanisms. The exosomes were isolated from the urine samples of patients with DKD (DKD-Exo). Later, they were taken up and internalized by MPC5 cells. MPC5 cells were co-cultured with DKD-Exo (45 μg/ml) for 24 h in the presence or absence of microRNA-145-5p (miR-145-5p) inhibitor, fasudil and pcDNA-Srgap2 transfection. MiR-145-5p and Srgap2 expression was evaluated using real-time quantitative PCR. The protein levels of Srgap2, Bcl-2, Bax, and cleaved caspase-3, as well as ROCK activity were determined using Western blotting. Cell apoptosis was measured using flow cytometry and the TUNEL assay. miR-145-5p expression in MPC5 cells exposed to DKD-Exo was markedly upregulated. miR-145-5p negatively regulated Srgap2 levels. Exposure of MPC5 cells to DKD-Exo reduced Srgap2 expression and activated ROCK, which was partly reversed by the presence of the miR-145-5p inhibitor or Srgap2 overexpression. The apoptosis of MPC5 cells exposed to DKD-Exo increased significantly, which was counteracted by the addition of the miR-145-5p inhibitor and fasudil. The results showed that urinary exosomal miR-145-5p from patients with DKD induced podocyte apoptosis by inhibiting Srgap2 and activating the RhoA/ROCK pathway, suggesting that urinary exosomal miR-145-5p is involved in the pathological process of DKD and could become a noninvasive diagnostic biomarker for DKD.

Integrating network pharmacology and experimental validation to decipher the mechanism of the Chinese herbal prescription modified Shen-Yan-Fang-Shuai formula in treating diabetic nephropathy

CONTEXT

Diabetic nephropathy (DN) is the main cause of end-stage renal disease. Modified Shen-Yan-Fang-Shuai formula (M-SYFSF) has excellent clinical efficacy in treating diabetic kidney disease. However, the potential mechanism of M-SYFSF remains unknown.

OBJECTIVE

To investigate the mechanism of M-SYFSF against DN by network pharmacological analysis and biological experiments.

MATERIALS AND METHODS

Utilizing a web-based pharmacology database, the potential mechanisms of M-SYFSF against DN were identified. In vivo experiments, male SD rats were injected with streptozotocin (50 mg/kg) and got uninephrectomy to construct a model of DN. M-SYFSF (11.34 g/kg/d) was gavaged once per day for 12 weeks after model establishment. In vitro experiments, human proximal tubular cells (HK-2) were performed with advanced glycation end-products (AGEs) (100 μg/mL), then intervened with M-SYFSF freeze-dried powder. Pathological staining, WB, IHC, ELISA were conducted to explore the mechanism of M-SYFSF against DN.

RESULTS

Network pharmacological analysis showed that MAPK pathway was the potential pathway. Results showed that compared with the Model group, M-SYFSF significantly reduced 24h urine albumin, UACR, and serum creatinine levels (54.90 ± 26.67 vs. 111.78 ± 4.28, 8.87 ± 1.69 vs. 53.94 ± 16.01, 11.56 ± 1.70 vs. 118.70 ± 49.57, respectively), and improved renal pathological changes. Furthermore, the intervention of M-SYFSF reduced the expression of pro-inflammatory cytokines and inhibited the activation of MAPK pathway in AGEs-treated HK-2 cells.

DISCUSSION AND CONCLUSION

M-SYFSF is likely to reduce inflammation in DN by inhibiting the MAPK pathway. It provides a theoretical basis for the clinical application of M-SYFSF in the treatment of DN.

Loperamide, a peripheral Mu-Opioid receptor agonist, attenuates chemotherapy-induced neuropathic pain in rats

Opioids are employed in the management of chemotherapy-induced neuropathic pain (CINP) when other pain management approaches have failed and proven ineffective. However, their use in CINP is generally considered as a second-line or adjunctive therapy owing to their central side effects and development of tolerance with their long-term usage. Targeting peripheral sites may offer several advantages over the conventional CNS-based approaches as peripheral targets modulate pain signals at their source, thereby relieving pain with higher specificity, efficacy and minimizing adverse effects associated with off-site CNS actions. Therefore, present study was designed with an aim to investigate the effect of loperamide, a peripherally acting mu-opioid receptor agonist, on paclitaxel-induced neuropathic pain in rats and elucidate its underlying mechanism. Loperamide treatment significantly attenuated mechanical, and cold hypersensitivity and produced significant place preference behaviour in neuropathic rats indicating its potential to treat both evoked and spontaneous pain. More importantly, loperamide treatment in naïve rats did not produce place preference to drug-paired chamber pointing towards its non-addictive analgesic potential. Further, molecular investigations revealed increased expression of ion channels such as TRPA1, TRPM8; voltage-gated sodium channels (VGSCs) and neuroinflammatory markers in the dorsal root ganglion (DRG) and lumbar (L4-L5) spinal cord of neuropathic rats, which was significantly downregulated upon loperamide treatment. These findings collectively suggest that activation of peripheral mu-opioid receptors contributes to the amelioration of both evoked and spontaneous pain in neuropathic rats by downregulating TRP channels and VGSCs along with suppression of oxido-nitrosative stress and neuroinflammatory cascade.

Effect of Prunetin on Streptozotocin-Induced Diabetic Nephropathy in Rats - a Biochemical and Molecular Approach

In the modern era, chronic kidney failure due to diabetes has spread across the globe. Prunetin (PRU), a component of herbal medicines, has a broad variety of pharmacological activities; these may help to slow the onset of diabetic kidney disease. The anti-nephropathic effects of PRU have not yet been reported. The present study explored the potential nephroprotective actions of PRU in diabetic rats. For 28 days, nephropathic rats were given oral doses of PRU (20, 40, and 80 mg/kg). Body weight, blood urea, creatinine, total protein, lipid profile, liver marker enzymes, carbohydrate metabolic enzymes, C-reactive protein, antioxidants, lipid peroxidative indicators, and the expression of insulin receptor substrate 1 (IRS-1) and glucose transporter 2 (GLUT-2) mRNA genes were all examined. Histological examinations of the kidneys, liver, and pancreas were also performed. The oral treatment of PRU drastically lowered the blood glucose, HbA1c, blood urea, creatinine, serum glutamic-oxaloacetic transaminase, serum glutamic pyruvic transaminase, alkaline phosphatase, lipid profile, and hexokinase. Meanwhile, the levels of fructose 1,6-bisphosphatase, glucose-6-phosphatase, and phosphoenol pyruvate carboxykinase were all elevated, but glucose-6-phosphate dehydrogenase dropped significantly. Inflammatory marker antioxidants and lipid peroxidative markers were also less persistent due to this administration. PRU upregulated the IRS-1 and GLUT-2 gene expression in the nephropathic group. The possible renoprotective properties of PRU were validated by histopathology of the liver, kidney, and pancreatic tissues. It is therefore proposed that PRU (80 mg/kg) has considerable renoprotective benefits in diabetic nephropathy in rats.

Health-Promoting Properties: Anti-Inflammatory and Anticancer Properties of Sambucus nigra L. Flowers and Fruits

Sambucus nigra L. has been used for centuries in traditional medicine thanks to its valuable healing properties. The healing properties result from its high content of biologically active compounds, mainly antioxidants, which contribute to its anti-inflammatory and anticancer properties. In our review, we have presented scientific studies evaluating the anti-inflammatory and anticancer effects of extracts and their components from S. nigra L. flowers and fruits. The results of the research show that the effect of antioxidant phytochemicals contained in their composition reduces the level of free radicals and pro-inflammatory cytokines, prevents mutations that increase the risk of cancer development, and inhibits cell proliferation, induction of apoptosis, and changes in intracellular signaling, consequently inhibiting the growth of malignant tumors and the formation of metastases. Flowers and fruits of S. nigra L. are a valuable source of nutraceutical and pharmacological substances that can support prevention and anti-inflammatory and oncological therapy without negative side effects for the patient.

A Mechanistic Insight into Beneficial Effects of Polyphenols in the Prevention and Treatment of Nephrolithiasis: Evidence from Recent In Vitro Studies

Nephrolithiasis is a pathological condition characterized by the formation of solid crystals in the kidneys or other parts of urinary tract. Kidney stones are a serious public health issue and financial burden for health care system, as well as a painful and uncomfortable condition for patients, resulting in renal tissue injury in severe cases. Dietary habits, low fluid and high salt intake predominantly, contribute to the development of kidney stones. Current research suggests that polyphenols have a protective effect in the pathogenesis of kidney stones. Polyphenols are a group of naturally occurring compounds found in plant-based foods such as fruits, vegetables, tea, and coffee. In this review, we explore mechanisms underlying the beneficial effects of polyphenols, such as oxidative stress reduction and modulation of inflammatory pathways, in various in vitro models of nephrolithiasis. Additionally, certain polyphenols, such as catechins found in green tea, have been shown to inhibit the formation and growth of kidney stones in animal studies. This review highlights the antioxidant and anti-inflammatory effects, as well as the inhibition of crystal formation, as results of polyphenol treatment in vitro. Further research is required to determine the specific effects of polyphenols on kidney stone formation in humans; however, current knowledge implicates that incorporating a variety of polyphenol-rich foods into the diet may be a beneficial strategy for individuals at risk of developing nephrolithiasis.

Flavonoids improve type 2 diabetes mellitus and its complications: a review

The prevalence of type 2 diabetes mellitus (T2DM) is increasing every year. Medications are currently the most common therapy for T2DM. However, these medications have certain adverse effects. In order to find safe and effective ways to improve this disease, researchers have discovered that some natural products can decrease blood sugar. Flavonoids are one of the most essential low molecular weight phenolic chemicals in the plant world, which widely exist in plant roots, stems, leaves, flowers, and fruits. They possess a variety of biological activities, including organ protection, hypoglycemic, lipid-lowering, anti-oxidative and anti-inflammatory effects. Some natural flavonoids ameliorate T2DM and its complications through anti-oxidation, anti-inflammatory action, glucose and lipid metabolism regulation, insulin resistance management, etc. Hence, this review aims at demonstrating the potential benefits of flavonoids in T2DM and its complications. This laid the foundation for the development of novel hypoglycemic medications from flavonoids.

Regulation of PKC/TLR-4/NF-kB signaling by sulbutiamine improves diabetic nephropathy in rats

One of the serious complications of diabetes mellitus is diabetic nephropathy (DN) which may finally lead to renal failure. The current study aimed to explore the effect of sulbutiamine, a synthetic derivative of vitamin B1, in streptozotocin (STZ)-induced DN and related pathways. Experimental DN was successfully induced 8 weeks after a single low dose of STZ (45 mg/kg, I.P.). Four groups of rats were used in this study and divided randomly into: control group, diabetic group, sulbutiamine control (control + sulbutiamine) group, and sulbutiamine-treated (60 mg/kg) (diabetic + sulbutiamine) group. The fasting blood glucose level (BGL) and the levels of kidney injury molecule-1 (Kim-1), urea, creatinine in serum, and the renal content of malondialdehyde (MDA), protein kinase C (PKC), toll-like receptor-4 (TLR-4) and nuclear factor kappa B (NF-κB) were determined. Additionally, tumor necrosis factor-α (TNF-α), interleukin-1β (IL-1β) and transforming growth factor-β1 (TGF-β1) contents were evaluated immunohistochemically. Sulbutiamine treatment decreased fasting BGL and improved the kidney function tests compared to diabetic rats. Moreover, TLR-4, NF-κB, MDA and PKC contents were substantially reduced following sulbutiamine treatment compared to the diabetic group. Sulbutiamine managed to obstruct the production of the pro-inflammatory TNF-α and IL-1β and suppressed TGF-β1 level, in addition to attenuating the histopathological changes associated with DN. This study revealed, for the first time, the ability of sulbutiamine to ameliorate STZ-induced diabetic nephropathy in rats. This nephroprotective outcome of sulbutiamine against DN may be attributed to glycemic control in addition to its anti-oxidative, anti-inflammatory and anti-fibrotic effects.

Comparative Efficacy of East Asian Herbal Formulae Containing Astragali Radix-Cinnamomi Ramulus Herb-Pair against Diabetic Peripheral Neuropathy and Mechanism Prediction: A Bayesian Network Meta-Analysis Integrated with Network Pharmacology

The Astragali Radix-Cinnamomi Ramulus herb-pair (ACP) has been widely used in the treatment of diabetic peripheral neuropathy (DPN) as part of East Asian herbal medicine (EAHM). Eligible randomized controlled trials (RCTs) were identified by searching 10 databases. The outcomes investigated were response rate, sensory nerve conduction velocity (SNCV), and motor nerve conduction velocity (MNCV) in four regions of the body. The compounds in the ACP and their targets of action, disease targets, common targets, and other relevant information were filtered using network pharmacology. Forty-eight RCTs, with 4308 participants, and 16 different interventions were identified. Significant differences were observed in the response rate, MNCV, and SNCV, as all EAHM interventions were superior to conventional medicine or lifestyle modification. The EAHM formula containing the ACP ranked highest in more than half of the assessed outcomes. Furthermore, major compounds, such as quercetin, kaempferol, isorhamnetin, formononetin, and beta-sitosterol, were found to suppress the symptoms of DPN. The results of this study suggest that EAHM may increase therapeutic efficacy in DPN management, and EAHM formulations containing the ACP may be more suitable for improving treatment response rates to NCV and DPN therapy.

Yiqi Huazhuo decoction increases insulin secretion in type 2 diabetic rats by regulating the pancreatic GPR40-IP3R-1 signaling pathway

Objective: Yiqi Huazhuo Decoction (YD) reduces blood glucose, glycated hemoglobin, body weight, and insulin resistance in patients with type 2 diabetes mellitus (T2DM), but its exact mechanisms are unknown. This study investigated the therapeutic effects and mechanisms of YD on impaired insulin secretion in T2DM rats.

Methods: T2DM rats were randomized to the model, YD-lo (15 mg/kg/d YD, 10 weeks), YD-hi (30 mg/kg/d YD, 10 weeks), positive drug (TAK-875), and healthy control groups. The rats underwent an oral glucose tolerance test (OGTT), glucose-stimulated insulin secretion (GSIS) test, and serum lipid measurements. High-fat and high-glucose-injured RIN-m5f cells were treated with YD (30 or 150 mg/mL) for 48 h. GPR40 and IP3R-1 expression levels were determined by immunofluorescence, qRT-PCR, and western blot.

Results: Compared with the model group, the OGTT area under the curve (AUC) in the YD-hi group was decreased by 26.7%, the insulin release test (IRT) AUC in the YD-hi group was increased by 45.9%, and the GSIS AUC was increased by 33.9% (p < 0.05). Compared with the model cells, the insulin secretion after glucose stimulation in the YD-hi group was increased by 24.5%, similar to the TAK-875 group (23.1%) (p > 0.05). GPR40 and IP3R-1 mRNA in the model cells were decreased by 49.5% and 51.2% compared with the control cells (p < 0.05). In the YD-hi group, GPR40 and IP3R-1 mRNA levels were increased by 58.1% and 39.3% (p < 0.05), similar to the TAK-875 group. The changes in protein expression were similar to mRNA.

Conclusion: YD promotes insulin secretion from pancreatic islet β-cell in T2DM rats by regulating the GPR40-IP3R-1 pathway, thereby reducing blood glucose.

The Effects of Momordica charantia on Type 2 Diabetes Mellitus and Alzheimer's Disease

T2DM is a complex metabolic disorder characterized by hyperglycemia and glucose intolerance. It is recognized as one of the most common metabolic disorders and its prevalence continues to raise major concerns in healthcare globally. Alzheimer's disease (AD) is a gradual neurodegenerative brain disorder characterized by the chronic loss of cognitive and behavioral function. Recent research suggests a link between the two diseases. Considering the shared characteristics of both diseases, common therapeutic and preventive agents are effective. Certain bioactive compounds such as polyphenols, vitamins, and minerals found in vegetables and fruits can have antioxidant and anti-inflammatory effects that allow for preventative or potential treatment options for T2DM and AD. Recently, it has been estimated that up to one-third of patients with diabetes use some form of complementary and alternative medicine. Increasing evidence from cell or animal models suggests that bioactive compounds may have a direct effect on reducing hyperglycemia, amplifying insulin secretion, and blocking the formation of amyloid plaques. One plant that has received substantial recognition for its numerous bioactive properties is Momordica charantia (M. charantia), otherwise known as bitter melon, bitter gourd, karela, and balsam pear. M. charantia is utilized for its glucose-lowering effects and is often used as a treatment for diabetes and related metabolic conditions amongst the indigenous populations of Asia, South America, India, and East Africa. Several pre-clinical studies have documented the beneficial effects of M. charantia through various postulated mechanisms. Throughout this review, the underlying molecular mechanisms of the bioactive components of M. charantia will be highlighted. More studies will be necessary to establish the clinical efficacy of the bioactive compounds within M. charantia to effectively determine its pertinence in the treatment of metabolic disorders and neurodegenerative diseases, such as T2DM and AD.

Nephroprotective plant species used in traditional Mayan Medicine for renal-associated diseases

ETHNOPHARMACOLOGICAL RELEVANCE

The prevalence of kidney disease has increased rapidly in recent years and has emerged as one of the leading causes of mortality worldwide. Natural products have been suggested as valuable nephroprotective agents due to their multi-target and synergistic effects on modulating important proteins involved in kidney injury. There is a large number of plant species that have been used traditionally for kidney-related conditions in Mesoamerican medicine by different cultural groups that could provide a valuable source of nephroprotective therapeutic candidates and could lead to potential drug discovery.

AIM OF REVIEW

This review aims to provide an overview of the currently known efficacy of plant species used traditionally in Mesoamerica by Mayan groups to treat kidney-related conditions and to analyze the phytochemical, pharmacological, molecular, toxicological, and clinical evidence to contribute to public health efforts and for directing future research.

METHODS

Primary sources of plant use reports for traditional kidney-related disorders in Mesoamerica were searched systematically from library catalogs, theses, and scientific databases (PubMed, Google Scholar; and Science Direct), and were filtered according to usage frequency in Mayan groups and plant endemism. The database of traditional plants was further analyzed based on associations with published reports of the phytochemical, pharmacological, molecular, toxicological, and clinical evidence.

RESULTS

The most reported kidney-related conditions used traditionally in Mayan medicine involve reducing renal damage (a cultural interpretation that considers an inflammatory or infectious condition), cleaning or purifying the blood and kidney, reducing kidney pain, and eliminating kidney stones. A total of 208 plants used for kidney-related problems by 10 Mayan groups were found, representing 143 native species, where only 42 have reported pharmacological activity against kidney damage, mainly approached by in vitro and in vivo models of chemical- or drug-induced nephrotoxicity, diabetes nephropathy, and renal injury produced by hypertension. Nephroprotective effects are mainly mediated by reducing oxidative stress, inflammatory response, fibrosis mechanisms, and apoptosis in the kidney. The most common nephroprotective compounds associated with traditional Mayan medicine were flavonoids, terpenoids, and phenolic acids. The most widely studied traditional plants in terms of pharmacological evidence, bioactive compounds, and mechanisms of action, are Annona muricata L., Carica papaya L., Ipomoea batatas (L.) Lam., Lantana camara L., Sechium edule (Jacq.) Sw., Tagetes erecta L., and Zea mays L. Most of the plant species with reported pharmacological activity against kidney damage were considered safe in toxicological studies.

CONCLUSION

Available pharmacological reports suggest that several herbs used in traditional Mayan medicine for renal-associated diseases may have nephroprotective effects and consistent pharmacological evidence, nephroprotective compounds, and mechanisms of action in different models of kidney injury. However, more research is required to fully understand the potential of traditional Mayan medicine in drug discovery given the limited ethnobotanical studies and data available for most species with regards to identification on bioactive components, pharmacological mechanisms, and the scarce number of clinical studies.

DL-3-n-butylphthalide (NBP) alleviates poststroke cognitive impairment (PSCI) by suppressing neuroinflammation and oxidative stress

Currently, the recovery of cognitive function has become an essential part of stroke rehabilitation. DL-3-n-butylphthalide (NBP) is a neuroprotective reagent and has been used in stroke treatment. Clinical studies have confirmed that NBP can achieve better cognitive outcomes in ischemic stroke patients than in healthy controls. In this study, we aimed to investigate the influences of NBP on cognitive function in an ischemic reperfusion (I/R) rat model. Our results showed that NBP profoundly decreased neurological scores, reduced cerebral infarct areas and enhanced cerebral blood flow (CBF). NBP potently alleviated poststroke cognitive impairment (PSCI) including depression-like behavior and learning, memory and social cognition impairments, in I/R rats. NBP distinctly suppressed the activation of microglia and astrocytes and improved neuron viability in the ischemic brain. NBP inhibited the expression of inflammatory cytokines, including interleukin-6 (IL-6), interleukin-1β (IL-1β) and tumor necrosis factor-α (TNF-α), by targeting the nuclear factor kappa B/inducible nitric oxide synthase (NF-κB/iNOS) pathway and decreased cerebral oxidative stress factors, including reactive oxygen species (ROS) and malondialdehyde (MDA), by targeting the kelch like ECH associated protein 1/nuclear factor-erythroid 2 p45-related factor 2 (Keap1/Nrf2) pathway in the ischemic brain. The current study revealed that NBP treatment improved neurological function and ameliorated cognitive impairment in I/R rats, possibly by synergistically suppressing inflammation and oxidative stress.

Cytokine expression profiles in white blood cells of patients with small fiber neuropathy

BACKGROUND

The role of cytokines in the pathophysiology, diagnosis, and prognosis of small fiber neuropathy (SFN) is incompletely understood. We studied expression profiles of selected pro- and anti-inflammatory cytokines in RNA from white blood cells (WBC) of patients with a medical history and a clinical phenotype suggestive for SFN and compared data with healthy controls.

METHODS

We prospectively recruited 52 patients and 21 age- and sex-matched healthy controls. Study participants were characterized in detail and underwent complete neurological examination. Venous blood was drawn for routine and extended laboratory tests, and for WBC isolation. Systemic RNA expression profiles of the pro-inflammatory cytokines interleukin (IL)-1ß, IL-2, IL-8, tumor necrosis factor-alpha (TNF) and the anti-inflammatory cytokines IL-4, IL-10, transforming growth factor beta-1 (TGF) were analyzed. Protein levels of IL-2, IL-8, and TNF were measured in serum of patients and controls. Receiver operating characteristic (ROC)-curve analysis was used to determine the accuracy of IL-2, IL-8, and TNF in differentiating patients and controls. To compare the potential discriminatory efficacy of single versus combined cytokines, equality of different AUCs was tested.

RESULTS

WBC gene expression of IL-2, IL-8, and TNF was higher in patients compared to healthy controls (IL-2: p = 0.02; IL-8: p = 0.009; TNF: p = 0.03) and discriminated between the groups (area under the curve (AUC) ≥ 0.68 for each cytokine) with highest diagnostic accuracy reached by combining the three cytokines (AUC = 0.81, sensitivity = 70%, specificity = 86%). Subgroup analysis revealed the following differences: IL-8 and TNF gene expression levels were higher in female patients compared to female controls (IL-8: p = 0.01; TNF: p = 0.03). The combination of TNF with IL-2 and TNF with IL-2 and IL-8 discriminated best between the study groups. IL-2 was higher expressed in patients with moderate pain compared to those with severe pain (p = 0.02). Patients with acral pain showed higher IL-10 gene expression compared to patients with generalized pain (p = 0.004). We further found a negative correlation between the relative gene expression of IL-2 and current pain intensity (p = 0.02). Serum protein levels of IL-2, IL-8, and TNF did not differ between patients and controls.

CONCLUSIONS

We identified higher systemic gene expression of IL-2, IL-8, and TNF in SFN patients than in controls, which may be of potential relevance for diagnostics and patient stratification.

Kaempferol ameliorates palmitate-induced lipid accumulation in HepG2 cells through activation of the Nrf2 signaling pathway

OBJECTIVES

Kaempferol (KMF), has beneficial effects against hepatic lipid accumulation. In this study, we aimed to investigate molecular mechanism underlying the protective effect of KMF on lipid accumulation.

METHODS

HepG2 cells were treated with different concentrations of KMF and 0.5 mM palmitate (PA) for 24  h. The mRNA and protein levels of genes involved in lipid metabolism were evaluated using real-time PCR and western blot. The expression of Nrf2 was silenced using siRNA.

RESULTS

Data indicated that KMF (20 μM) reversed PA-induced increased triglyceride (TG) levels and total lipid content. These effects were accompanied by down-regulation of the mRNA and protein levels of lipogenic genes (FAS, ACC and SREBP1), and up-regulation of genes related to fatty acid oxidation (CPT-1, HADHα and PPARα). Kaempferol significantly decreased the levels of the oxidative stress markers (ROS and MDA) and enhanced the activities of antioxidant enzymes SOD and GPx in PA-challenged cells. Luciferase analysis showed that KMF increased the transactivation of Nrf2 in hepatocytes. The results also revealed that KMF-mediated activation of Nrf2 target genes was suppressed by Nrf2 siRNA. Furthermore, Nrf2 siRNA abolished the KMF-induced reduction in ROS and MDA levels in PA treated cells. In addition, the inhibitory effect of KMF on TG levels and the mRNA and protein levels of FAS, ACC and SREPB-1 were significantly abolished by Nrf2 inhibition. Nrf2 inhibition also suppressed the KMF-induced activation of genes involved in β oxidation (CPT-1 and PPAR-α).

CONCLUSION

The results suggest that KMF protects HepG2 cells from PA-induced lipid accumulation via activation of the Nrf2 signaling pathway.

Dapagliflozin alleviates renal fibrosis in a mouse model of adenine-induced renal injury by inhibiting TGF-β1/MAPK mediated mitochondrial damage

Renal fibrosis is a common pathological outcome of various chronic kidney diseases, and as yet, there is no specific treatment. Dapagliflozin has shown renal protection in some clinical trials as a glucose-lowering drug, but its role and mechanism on renal fibrosis remain unclear. In this study, we used a 0.2% adenine diet-induced renal fibrosis mouse model to investigate whether dapagliflozin could protect renal function and alleviate renal fibrosis in this animal model. In vivo, we found that dapagliflozin's protective effect on renal fibrosis was associated with 1) sustaining mitochondrial integrity and respiratory chain complex expression, maintained the amount of mitochondria; 2) improving fatty acid oxidation level with increased expression of CPT1-α, PPAR-α, ACOX1, and ACOX2; 3) reducing inflammation and oxidative stress, likely via regulation of IL-1β, IL-6, TNF-α, MCP-1, cxcl-1 expression, and glutathione (GSH) activity, superoxide dismutase (SOD) and malondialdehyde (MDA) levels; and 4) inhibiting the activation of the TGF-β1/MAPK pathway. In HK2 cells treated with TGF-β1, dapagliflozin reduced the expression of FN and α-SMA, improved mitochondrial respiratory chain complex expression, and inhibited activation of the TGF-β1/MAPK pathway.

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.

Activation of Nrf2 signaling: A key molecular mechanism of protection against cardiovascular diseases by natural products

Cardiovascular diseases (CVD) are a group of cardiac and vascular disorders including myocardial ischemia, congenital heart disease, heart failure, hypertension, atherosclerosis, peripheral artery disease, rheumatic heart disease, and cardiomyopathies. Despite considerable progress in prophylaxis and treatment options, CVDs remain a leading cause of morbidity and mortality and impose an extremely high socioeconomic burden. Oxidative stress (OS) caused by disequilibrium in the generation of reactive oxygen species plays a crucial role in the pathophysiology of CVDs. Nuclear erythroid 2-related factor 2 (Nrf2), a transcription factor of endogenous antioxidant defense systems against OS, is considered an ideal therapeutic target for management of CVDs. Increasingly, natural products have emerged as a potential source of Nrf2 activators with cardioprotective properties and may therefore provide a novel therapeutic tool for CVD. Here, we present an updated comprehensive summary of naturally occurring products with cardioprotective properties that exert their effects by suppression of OS through activation of Nrf2 signaling, with the aim of providing useful insights for the development of therapeutic strategies exploiting natural products.

Betaine Attenuates Chronic Constriction Injury-Induced Neuropathic Pain in Rats by Inhibiting KIF17-Mediated Nociception

Kinesin superfamily proteins transport a diverse range of cargo, including excitatory receptors to the dendrite and axon of a neuron via retrograde and anterograde fashions along microtubules, causing central sensitization and neuropathic pain. In this study, we have performed in silico molecular dynamics simulation to delineate the dynamic interaction of betaine with KIF17, a kinesin protein, known to be involved in neuropathic pain. The results from the molecular dynamics study suggest that the betaine-KIF17 complex is stabilized through hydrogen bonding, polar interactions, and water bridges. Findings from in vivo studies suggest a significant increase in pain hypersensitivity, oxido-nitrosative stress, and KIF17 overexpression in the sciatic nerve, dorsal root ganglion (DRG), and spinal cord of nerve-injured rats, which was significantly attenuated on treatment with betaine. Betaine treatment also restored the increased NR2B expressions and levels of proinflammatory cytokines and neuropeptides in the DRG and spinal cord of nerve-injured rats. Findings from the current study suggest that betaine attenuates neuropathic pain in rats by inhibiting KIF17-NR2B-mediated neuroinflammatory signaling.

Kaempferol attenuated diabetic nephropathy by reducing apoptosis and promoting autophagy through AMPK/mTOR pathways

INTRODUCTION

Renal podocyte injury, apoptosis and autophagy are involved in the occurrence and development of diabetic nephropathy (DN). Kaempferol (KPF) has the promotion of autophagy and inhibition of apoptosis properties in the development of miscellaneous diseases, but these functions in DN have not yet been elucidated.

METHODS

We used db/db mice to evaluate the protective role of KPF on DN. The anti-DN effect of KPF was evaluated by urine albumin-to-creatinine ratio and pathological changes of kidney tissue. Injury of podocytes was observed through Transmission electron microscopy. Immunofluorescence, Western blot, and Immunohistochemistry were used to detect the protein expression of podocyte-associated molecules, autophagy, and AMPK/mTOR pathway.

RESULTS

We demonstrated that KPF treatment significantly attenuated diabetes-induced albuminuria and glycolipid metabolism dysfunction. In addition, KPF alleviated mesangial matrix expansion, glomerular basement membrane thickening and loss or fusion of podocytes. Mechanistically, KPF treatment regulated the expression of autophagic proteins (upregulated LC3II, Beclin-1, Atg7 and Atg 5, and downregulated p62/SQSTM1), accompanied by inhibited renal apoptosis (downregulated Caspase 3 and Bax, and upregulated Bcl-2). KPF could significantly regulate the AMPK/mTOR signaling pathways by increasing p-AMPK and decreasing p-mTOR expressions.

DISCUSSION

In conclusion, KPF might have a protective effect on DN through reduced apoptosis and enhanced podocytes autophagy, which were correlated with regulating AMPK/mTOR pathways.

Identification of Markers for Diagnosis and Treatment of Diabetic Kidney Disease Based on the Ferroptosis and Immune

BACKGROUND

In advanced diabetic kidney disease (DKD), iron metabolism and immune dysregulation are abnormal, but the correlation is not clear. Therefore, we aim to explore the potential mechanism of ferroptosis-related genes in DKD and their relationship with immune inflammatory response and to identify new diagnostic biomarkers to help treat and diagnose DKD.

METHODS

Download data from gene expression omnibus (GEO) database and FerrDb database, and construct random forest tree (RF) and support vector machine (SVM) model to screen hub ferroptosis genes (DE-FRGs). We used consistent unsupervised consensus clustering to cluster DKD samples, and enrichment analysis was performed by Gene Set Variation Analysis (GSVA), Gene Ontology (GO), and Kyoto Encyclopedia of Genes and Genomes (KEGG) and then assessed immune cell infiltration abundance using the single-sample gene set enrichment analysis (ssGSEA) and CIBERSORT algorithms. Ferroptosis scoring system was established based on the Boruta algorithm, and then, core compounds were screened, and binding sites were predicted by Coremine Medical database.

RESULTS

We finally established a 7-gene signature (DUSP1, PRDX6, PEBP1, ZFP36, GABARAPL1, TSC22D3, and RGS4) that exhibited good stability across different datasets. Consistent clustering analysis divided the DKD samples into two ferroptosis modification patterns. Meanwhile, autophagy and peroxisome pathways and immune-related pathways can participate in the regulation of ferroptosis modification patterns. The abundance of immune cell infiltration differs significantly across patterns. Further, molecular docking results showed that the core compound could bind to the protein encoded by the core gene.

CONCLUSIONS

Our findings suggest that ferroptosis modification plays a crucial role in the diversity and complexity of the DKD immune microenvironment, and the ferroptosis score system can be used to effectively verify the relationship between ferroptosis and immune cell infiltration in DKD patients. Kaempferol and quercetin may be potential drugs to improve the immune and inflammatory mechanisms of DKD by affecting ferroptosis.