Puerarin prevents cataract development and progression in diabetic rats through Nrf2/HO‑1 signaling

Breaking Barriers: Nanomedicine-Based Drug Delivery for Cataract Treatment

Cataract is a leading cause of blindness globally, and its surgical treatment poses a significant burden on global healthcare. Pharmacologic therapies, including antioxidants and protein aggregation reversal agents, have attracted great attention in the treatment of cataracts in recent years. Due to the anatomical and physiological barriers of the eye, the effectiveness of traditional eye drops for delivering drugs topically to the lens is hindered. The advancements in nanomedicine present novel and promising strategies for addressing challenges in drug delivery to the lens, including the development of nanoparticle formulations that can improve drug penetration into the anterior segment and enable sustained release of medications. This review introduces various cutting-edge drug delivery systems for cataract treatment, highlighting their physicochemical properties and surface engineering for optimal design, thus providing impetus for further innovative research and potential clinical applications of anti-cataract drugs.

Exploring the molecular mechanism of Yinao Fujian formula on ischemic stroke based on network pharmacology and experimental verification

Background

Ischemic stroke (IS) is a leading cause of long-term disability and even mortality, threatening people's lives. Yinao Fujian (YNFJ) formula is a Traditional Chinese Medicine formula that has been widely used to treat patients with IS. However, the molecular mechanism of YNFJ for the treatment of IS is still elusive. Our study aimed to explore the potential protective effect and the underlying mechanisms of YNFJ on IS using a network pharmacology approach coupled with experimental validation.

Materials and methods

Effective compounds of YNFJ were collected from BATMAN-TCM and TCMSP databases, while IS targets were obtained from GeneCards, OMIM, TTD and DrugBank databases. The protein-protein interaction (PPI) network was constructed to further screen the hub targets of YNFJ in IS treatment. GO and KEGG enrichment analyses were used to identify the critical biological processes and signaling pathways of YNFJ for IS. Moreover, Nissl staining, HE, TTC staining and Tunel staining were used in the MCAO model to prove the neuroprotective effect of YNFJ. Oxidative damage, inflammatory factor release and related pathways were tested in MCAO rat model and hypoxia-induced BV2 cell model, respectively.

Results

We found that YNFJ treatment significantly alleviated MCAO-induced nerve damage and apoptosis. Then, network pharmacology screening combined with literature research revealed IL6, TNF, PTGS2, NFKBIA and NFE2L2 as the critical targets in a PPI network. Moreover, the top 20 signaling pathways and biological processes associated with the protective effects of YNFJ on IS were enriched through GO and KEGG analyses. Further analysis indicated that NF-κB and Nrf2/HO-1 signaling pathways might be highly involved in the protective effects of YNFJ on IS. Finally, in vitro and in vivo experiments confirmed that YNFJ inhibited the release of inflammatory factors (IL-6 and TNF-α) and MDA content, and increased the activity of SOD. In terms of the mechanism, YNFJ inhibited the release of inflammatory factors by suppressing the NF-κB pathway and decreased the expression of iNOS and COX-2 to protect microglia from inflammation damage. In addition, YNFJ initiated the dissociation of Keap-1 and Nrf2, and activated the downstream protein HO-1, NQO1, thus decreasing oxidative stress.

Conclusion

Taken together, the findings in our research showed that the protective effects of YNFJ on IS were mainly achieved by regulating the NF-κB and Nrf2/HO-1 signaling pathways to inhibit oxidative stress damage and inflammatory damage of microglia.

Antioxidant System and Endoplasmic Reticulum Stress in Cataracts

The primary underlying contributor for cataract, a leading cause of vision impairment and blindness worldwide, is oxidative stress. Oxidative stress triggers protein damage, cell apoptosis, and subsequent cataract formation. The nuclear factor-erythroid 2-related factor 2 (Nrf2) serves as a principal redox transcriptional factor in the lens, offering a line of defense against oxidative stress. In response to oxidative challenges, Nrf2 dissociates from its inhibitor, Kelch-like ECH-associated protein 1 (Keap1), moves to the nucleus, and binds to the antioxidant response element (ARE) to activate the Nrf2-dependent antioxidant system. In parallel, oxidative stress also induces endoplasmic reticulum stress (ERS). Reactive oxygen species (ROS), generated during oxidative stress, can directly damage proteins, causing them to misfold. Initially, the unfolded protein response (UPR) activates to mitigate excessive misfolded proteins. Yet, under persistent or severe stress, the failure to rectify protein misfolding leads to an accumulation of these aberrant proteins, pushing the UPR towards an apoptotic pathway, further contributing to cataractogenesis. Importantly, there is a dynamic interaction between the Nrf2 antioxidant system and the ERS/UPR mechanism in the lens. This interplay, where ERS/UPR can modulate Nrf2 expression and vice versa, holds potential therapeutic implications for cataract prevention and treatment. This review explores the intricate crosstalk between these systems, aiming to illuminate strategies for future advancements in cataract prevention and intervention. The Nrf2-dependent antioxidant system communicates and cross-talks with the ERS/UPR pathway. Both mechanisms are proposed to play pivotal roles in the onset of cataract formation.

Astragalin attenuates diabetic cataracts via inhibiting aldose reductase activity in rats

AIM

To investigate the aldose reductase (AR) inhibition capacity of astragalin (AST) against streptozoticin-induced diabetic cataracts (DCs) in rats.

METHODS

Ex vivo investigations were conducted by treating the lens of a goat placed for 72h in artificial aqueous humor (AAH) of pH 7.8 at room temperature with cataract-causing substance (55 mmol/L of galactose) and in vivo studies were performed on rats via induction with streptozotocin. AST was administered at different dose levels and scrutinize for DC activity.

RESULTS

In diabetic rats, AST improved the body weight, blood insulin, and glucose as well as the levels of galactitol in a dose-dependent way, other biochemical parameters i.e. inflammatory mediators and cytokines, and also suppress AR activity. The level of the antioxidant parameters such as superoxide dismutase (SOD), catalase (CAT), and glutathione (GSH) activity were also altered on a diabetic lens after the administration of the AST.

CONCLUSION

AST protects against lens opacification to avoid cataracts and polyols formation, indicating that it could be used as a potential therapeutic agent for diabetes.

Genome-wide identification and expression pattern analysis of R2R3-MYB transcription factor gene family involved in puerarin biosynthesis and response to hormone in Pueraria lobata var. thomsonii

BACKGROUND

R2R3-MYB transcription factors regulate secondary metabolism, stress responses and development in various plants. Puerarin is a bioactive ingredient and most abundant secondary metabolite isolated from Pueraria lobata. The biosynthesis of puerarin proceeds via the phenylpropanoid pathway and isoflavonoids pathway, in which 9 key enzymes are involved. The expression of these structural genes is under control of specific PtR2R3-MYB genes in different plant tissues. However, how PtR2R3-MYB genes regulates structural genes in puerarin biosynthesis remains elusive. This study mined the PtR2R3-MYB genes involved in puerarin biosynthesis and response to hormone in Pueraria lobata var. thomsonii.

RESULTS

A total of 209 PtR2R3-MYB proteins were identified, in which classified into 34 subgroups based on the phylogenetic topology and the classification of the R2R3-MYB superfamily in Arabidopsis thaliana. Furtherly physical and chemical characteristics, gene structure, and conserved motif analysis were also used to further analyze PtR2R3-MYBs. Combining puerarin content and RNA-seq data, speculated on the regulated puerarin biosynthesis of PtR2R3-MYB genes and structural genes, thus 21 PtR2R3-MYB genes and 25 structural genes were selected for validation gene expression and further explore its response to MeJA and GSH treatment by using qRT-PCR analysis technique. Correlation analysis and cis-acting element analysis revealed that 6 PtR2R3-MYB genes (PtMYB039, PtMYB057, PtMYB080, PtMYB109, PtMYB115 and PtMYB138) and 7 structural genes (PtHID2, PtHID9, PtIFS3, PtUGT069, PtUGT188, PtUGT286 and PtUGT297) were directly or indirectly regulation of puerarin biosynthesis in ZG11. It is worth noting that after MeJA and GSH treatment for 12-24 h, the expression changes of most candidate genes were consistent with the correlation of puerarin biosynthesis, which also shows that MeJA and GSH have the potential to mediate puerarin biosynthesis by regulating gene expression in ZG11.

CONCLUSIONS

Overall, this study provides a comprehensive understanding of the PtR2R3-MYB and will paves the way to reveal the transcriptional regulation of puerarin biosynthesis and response to phytohormone of PtR2R3-MYB genes in Pueraria lobata var. thomsonii.

Antihyperglycemic Effect of Rhamnus alaternus L. Aqueous Extract in Streptozotocin-induced Diabetic Rats

BACKGROUND

Traditionally, the aerial parts of Rhamnus alaternus L. have been widely used in Mediterranean countries, including Morocco, to cure diabetes.

AIM

This study aimed to evaluate the antidiabetic effect of Rhamnus alaternus aqueous extract in streptozotocin(STZ)-induced diabetic rats.

OBJECTIVE

This work aimed to evaluate the antihyperglycemic effect of Rhamnus alaternus aqueous extract (RAAE) in normal and diabetic rats. Then the phytochemical composition, antioxidant capacity, and potential toxicity of RAAE were also assessed.

METHODS

The effects of acute (6 h) and subchronic (7 days) oral administration of RAAE (20 mg/kg) on blood glucose levels and lipid profiles were evaluated in normal and diabetic rats. Besides, a preliminary phytochemical screening, quantification of phenolic, flavonoid, and tannin contents as well as the antioxidant activity, using the DPPH method, were evaluated. Additionally, the toxicity of the aqueous extract (5 mg/kg) was also studied and the LD50 value was determined.

RESULTS

RAAE (20 mg/kg) over 7 days of oral administration significantly decreased the blood glucose levels both in normal and diabetic rats. In diabetic rats, this extract also improved oral glucose tolerance. In addition, RAAE possessed significant antioxidant activity. According to preliminary phytochemical research, RAAE contains several chemical compounds, including alkaloids, polyphenols, flavonoids, cyanidins, anthraquinones, and sterols. On the other hand, the quantitative phytochemical study of the aqueous extract revealed a considerable amount of total phenolic compounds (497.93 ± 3.38 mg GAE/1g of RAAE), flavonoids (100.42 ± 0.32 mg RE/ g of RAAE), and tannins (14.32 ± 0.37 mg CE/1g of RAAE).

CONCLUSION

We conclude that RAAE exerts a significant antihyperglycemic effect in STZ-induced diabetic rats at a low dose. Indeed, more research is still required to support the use of this plant in the Moroccan population's diabetes care.

Assessment of heavy metals contamination and human health risk assessment of the commonly consumed medicinal herbs in China

This study investigates heavy metal contamination of commonly consumed medicinal herbs and human health risks to the Chinese population arising from the consumption of herbs that contain potentially harmful elements. Food safety standards for Chinese residents are becoming stricter, and much work in this field needs to be performed. This study examines Co, Ba, Fe, Cr, Mn, Ni, Zn, As, Cd, Pb, Cu, Be, Sb, and Bi concentrations in four regularly consumed Chinese herb species: Radix Paeoniae Alba (RPA), Radix Angelicae Dahuricae (RAD), Rhizoma Atractylodis Macrocephalae (RAM), and Radix Puerariae (RP). A pollution status examination and evaluation of heavy metals in RPA, RAD, RAM, and RP were performed. The human health risk assessment associated with the intake of potentially harmful elements in herbs was calculated in terms of the estimated daily intake (EDI), the target hazard quotient (THQ), the estimated hazard index (HI), and the lifetime cancer risk (CR). The mean single-factor pollution index (PI) showed that in the RPA, RAD, RAM, and RP samples, approximately 10.0%, 10.0%, 30.0%, and 10.0%, respectively, were polluted by Cd. The present study indicated that the pattern of consumption of the studied herbs in China does not seem to suggest an excessive health hazard associated with any of the toxic elements studied.

Puerarin: A Potential Therapeutic for SARS-CoV-2 and Hantavirus Co-Infection

Patients with Hantavirus-caused epidemic hemorrhagic fever (EHF) are at risk of contracting severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). However, there is currently no validated EHF/SARS-CoV-2 strategy. Several studies have recently shown Puerarin, a natural product, has potent antiviral properties. The goal of present study was to determine the mechanism of puerarin in patients with EHF/COVID-19. We use network pharmacology and bioinformatics to investigate the possible pharmacological targets, bioactivities, and molecular mechanisms of puerarin in the treatment of patients with EHF/SARS-CoV-2. The study investigated the pathogenesis of COVID-19 and EHF and the signaling pathway impacted by puerarin. 68 common genes linked to puerarin and EHF/SARS-CoV-2 were discovered during the investigation. By using protein-protein interaction (PPI) network, we identified RELA, JUN, NF-B1, NF-B2, and FOS as potential therapeutic targets. The bioactivity and signaling pathways of puerarin have also been demonstrated in the treatment of EHF and COVID-19. According to present study, puerarin could reduce excessive immune responses and inflammation through the NF-B, TNF, and HIF-1 signaling pathways. This study explored the potential therapeutic targets and mechanisms of Puerarin in the treatment of EHF/COVID-19.

Activation of Nrf2/HO-1 Antioxidant Pathway by Heme Attenuates Calcification of Human Lens Epithelial Cells

Cataract, an opacification in the crystalline lens, is a leading cause of blindness. Deposition of hydroxyapatite occurs in a cataractous lens that could be the consequence of osteogenic differentiation of lens epithelial cells (LECs). Nuclear factor erythroid 2-related factor 2 (Nrf2) controls the transcription of a wide range of cytoprotective genes. Nrf2 upregulation attenuates cataract formation. Here we aimed to investigate the effect of Nrf2 system upregulation in LECs calcification. We induced osteogenic differentiation of human LECs (HuLECs) with increased phosphate and calcium-containing osteogenic medium (OM). OM-induced calcium and osteocalcin deposition in HuLECs. We used heme to activate Nrf2, which strongly upregulated the expression of Nrf2 and heme oxygenase-1 (HO-1). Heme-mediated Nrf2 activation was dependent on the production of reactive oxygens species. Heme inhibited Ca deposition, and the OM-induced increase of osteogenic markers, RUNX2, alkaline phosphatase, and OCN. Anti-calcification effect of heme was lost when the transcriptional activity of Nrf2 or the enzyme activity of HO-1 was blocked with pharmacological inhibitors. Among products of HO-1 catalyzed heme degradation iron mimicked the anti-calcification effect of heme. We concluded that heme-induced upregulation of the Nrf2/HO-1 system inhibits HuLECs calcification through the liberation of heme iron.

The Effects of Antioxidants from Natural Products on Obesity, Dyslipidemia, Diabetes and Their Molecular Signaling Mechanism

Obesity is a risk factor that leads to the development of other diseases such as dyslipidemia and diabetes. These three metabolic disorders can occur simultaneously, hence, the treatment requires many drugs. Antioxidant compounds have been reported to have activities against obesity, dyslipidemia and diabetes via several mechanisms. This review aims to discuss the antioxidant compounds that have activity against obesity, dyslipidemia and diabetes together with their molecular signaling mechanism. The literature discussed in this review was obtained from the PUBMED database. Based on the collection of literature obtained, antioxidant compounds having activity against the three disorders (obesity, dyslipidemia and diabetes) were identified. The activity is supported by various molecular signaling pathways that are influenced by these antioxidant compounds, further study of which would be useful in predicting drug targets for a more optimal effect. This review provides insights on utilizing one of these antioxidant compounds as opposed to several drugs. It is hoped that in the future, the number of drugs in treating obesity, dyslipidemia and diabetes altogether can be minimized consequently reducing the risk of side effects.

Molecular Mechanism of Puerarin Against Diabetes and its Complications

Puerarin is a predominant component of Radix Puerarin. Despite its anti-tumor and anti-virus effects and efficacy in improving cardiovascular or cerebrovascular diseases and preventing osteoporosis, it has been shown to protect against diabetes and its complications. This review summarizes the current knowledge on Puerarin in diabetes and related complications, aiming to provide an overview of antidiabetic mechanisms of Puerarin and new targets for treatment.

Fundamentals of Diabetic Cataractogenesis and Promising Ways of its Pharmacological Correction

Cataracts in diabetes mellitus lead to decreased visual function and blindness. Cataract surgery for diabetes mellitus has limitations and complications. The search for effective means of conservative cataract therapy continues. The review presents the analysis of data from scientific sources, mainly for 2015–2020 using Internet resources (PubMed, Web of Science, Medline, eLibrary.Ru, Cyberleninka). In the work, diabetic cataractogenesis is presented as a sum of interrelated pathobiochemical processes. The main ones are the polyol pathway of glucose conversion, non-enzymatic glycation and oxidative modification of lens proteins, which are enhanced in diabetes mellitus. The lens has a high protein content. The formation of high molecular weight protein aggregates is of particular importance for the appearance of light scattering zones and a decrease in lens transparency. This review presents data on anti-cataract compounds that affect post-translational crystallin modification, prevent osmotic and oxidative stress in the lens, and exhibit antiglycation properties. This information shows that the search for means of pharmacological correction of cataractogenesis should be carried out among compounds with antioxidant and antiglycation activity. 

Pueraria tuberosa: A Review on Traditional Uses, Pharmacology, and Phytochemistry

Pueraria tuberosa (Roxb. ex Willd.) DC. (Fabaceae), also known as Indian Kudzu (vidari kand), is a perennial herb distributed throughout India and other Asian countries. Traditionally, tuber and leaves of this plant have extensively been reported for nutritional and medicinal properties in Ayurveda as well as in Chinese traditional practices. The objective of the present review is to compile and update the published data on traditional uses, pharmacological potential, and phytochemistry of compounds isolated from the plant Pueraria tuberosa. P. tuberosa extracts and its purified compounds possess multiple activities such as anticancer, anticonvulsant, antidiabetic, antifertility, anti-inflammatory, antioxidant, anti-stress, antiulcerogenic, cardioprotective, hypolipidemic, hepatoprotective, immunomodulatory, nephroprotective, nootropic, neuroprotective, and wound healing. Tuber and leaf extracts of P. tuberosa contain several bioactive constituents such as puerarin, daidzein, genistein, quercetin, irisolidone, biochanin A, biochanin B, isoorientin, and mangiferin, which possess an extensive range of pharmacological activities. The extensive range of pharmacological properties of P. tuberosa provides opportunities for further investigation and presents a new approach for the treatment of ailments. Many phytochemicals have been identified and characterized from P. tuberosa; however, some of them are still unexplored, and there is no supporting data for their activities and exact mechanisms of action. Therefore, further investigations are warranted to unravel the mechanisms of action of individual constituents of this plant.

Potential Protective and Therapeutic Roles of the Nrf2 Pathway in Ocular Diseases: An Update

Nuclear factor- (erythroid-derived 2-) like 2 (Nrf2) is a regulator of many processes of life, and it plays an important role in antioxidant, anti-inflammatory, and antifibrotic responses and in cancer. This review is focused on the potential mechanism of Nrf2 in the occurrence and development of ocular diseases. Also, several Nrf2 inducers, including noncoding RNAs and exogenous compounds, which control the expression of Nrf2 through different pathways, are discussed in ocular disease models and ocular cells, protecting them from dysfunctional changes. Therefore, Nrf2 might be a potential target of protecting ocular cells from various stresses and preventing ocular diseases.

Standard Puerarin Prevents Diabetic Renal Damage by Inhibiting miRNA-140-5p Expression

AIM

This study was designed to use in vivo and in vitro approaches to evaluate puerarin in diabetes-induced renal injury.

MATERIALS AND METHODS

SD rats were divided into NC (normal control), Model (diabetic induced renal injury model), SP-L (model rats treated with low-dose standard puerarin), SP-M (model rats treated with middle-dose standard puerarin), and SP-H (model rats treated with high-dose standard puerarin) groups. We evaluated fasting blood-glucose (FBG), urinary albumin/creatinine ratio (UACR), body weight, and kidney index (KI) in the different groups. TNF-α, IL-1β, and IL-6 concentrations were measured using Elisa assays. HE staining and TUNEL assays were used to evaluate pathology and apoptosis in kidney tissues, respectively. Relative gene and protein expression was measured using RT-qPCR and Western blot assays. Apoptosis was measured using flow cytometry. The correlation between miRNA-145-5p and TLR4 was assessed using dual-luciferase reporter gene assays.

RESULTS

The pathology and apoptosis cell number were deteriorate in Model group; TNF-α, IL-1β and IL-6 concentrations, FGB, UACR and KI were increased and body weight was depressed; meanwhile, relative gene and proteins expressions (miRNA-145-5p, TLR4, MyD88 and NF-κB p65) were significantly different in Model group in vivo and vitro study compared with NC group. SP treatment significantly improved the pathology and apoptosis levels in the tissues, as well as TNF-α, IL-1β and IL-6 concentrations, FGB, UACR, body weight, and KI. In vitro cell studies revealed that SP could prevent renal injury induced by diabetes through the miRNA-145-5p/TLR4 axis.

CONCLUSION

SP prevents diabetes-induced renal damage via miRNA-145-5p overexpression and reduces TLR4/MyD88/NF-κB (p65) pathway activation in vitro and in vivo.