Silymarin prevents endothelial dysfunction by upregulating Erk-5 in oxidized LDL exposed endothelial cells

Extracellular signal-regulated kinase (Erk)-5 is a key mediator of endothelial cell homeostasis, and its inhibition causes loss of critical endothelial markers leading to endothelial dysfunction (ED). Circulating oxidized low-density lipoprotein (oxLDL) has been identified as an underlying cause of ED and atherosclerosis in metabolic disorders. Silymarin (Sym), a flavonolignan, possesses various pharmacological activities however its preventive mechanism in ED warrants further investigation. Here, we have examined the effects of Sym in regulating the expression of Erk-5 and ameliorating ED using in vitro and in vivo models. Primary human umbilical vein endothelial cells (pHUVECs) viability was measured by MTT assay; mRNA and protein expression by RT-qPCR and Western blotting; tube-formation assay was performed to examine endothelialness. In in-vivo experiments, normal chow-fed mice (control) or high-fat diet (HFD)-fed mice were administered Sym or Erk-5 inhibitor (BIX02189) and body weight, blood glucose, plasma-LDL, oxLDL levels, and expression of EC markers in the aorta were examined. Sym (5 μg/ml) maintained the viability and tube-formation ability of oxLDL exposed pHUVECs. Sym increased the expression of Erk-5, vWF, and eNOS and decreased ICAM-1 at transcription and translation levels in oxLDL-exposed pHUVECs. In HFD-fed mice, Sym reduced the body weight, blood glucose, LDL-cholesterol, and oxLDL levels, and increased the levels of vWF and eNOS along with Erk-5 and decreased the level of ICAM-1 in the aorta. These data suggest that Sym could be a potent anti-atherosclerotic agent that could elevate Erk-5 level in the ECs and prevent ED caused by oxidized LDL during HFD-induced obesity in mice.

In vitro and in silico investigation of glycyrrhizic acid encapsulated zein nanoparticles: A synergistic targeted drug delivery approach for breast cancer

This study presents an innovative approach for targeted drug delivery through the development of Glycyrrhizic acid-loaded zein nanoparticles (GA-LNPs) as a proficient carrier system. The juxtaposition of zein, a hydrophobic biological macromolecule as a protein carrier, and Glycyrrhizic acid (GA), a hydrophilic therapeutic compound, exemplifies the adaptability of hydrocolloids within cutting-edge drug delivery systems. The characterization and functional traits of research encompass multifaceted analyses of natural macromolecules, which elucidate the homogeneous and spherical morphology of GA-LNPs with an average size of 170.49 nm. The controlled drug release profile of GA, orchestrated under simulated gastrointestinal conditions, adheres to diffusion-based Higuchi kinetics, reflecting the controlled release of the natural macromolecules. The intermolecular interactions among Zein, GA, and cross-linker EDC, facilitated through molecular dynamics simulations, fortify the structural integrity of the encapsulation matrix. In Vitro studies revealed enhanced cellular uptake of GA-LNPs in MCF-7 breast cancer cells. This cellular internalization was further confirmed through cytotoxicity assessments using MTT and apoptosis assays (fluorescence microscopy), which demonstrated the prominent anticancer effects of GA-LNPs on MCF-7 in time/dose-dependent manner. The successful formulation of GA-LNPs, coupled with their sustained release and potent anticancer properties, makes them a potential platform for advanced targeted therapeutic strategies in biomedical applications.

Synthesis, physiochemical characterization, molecular docking study, and anti-breast cancer activity of silymarin loaded zein nanoparticles

Breast cancer is a major cause of death in women worldwide leading to requirement of new therapeutic strategies. Silymarin demonstrated the anti-cancer activity however, due to low bioavailability its use is restricted. This study aimed to improve the solubility of silymarin by developing a silymarin loaded zein nanoparticles (SLNPs) which was stabilized by beta cyclodextrin. Comprehensive physiochemical characterization studies based on DLS, FTIR, UV-Vis Spectroscopy, FE-SEM, TEM, XRD, DSC, NMR and TGA confirmed the successful synthesis of SLNPs via an anti-solvent precipitation method. FE-SEM and TEM images demonstrated the uniform size and spherical shape of nanoparticles with encapsulation and loading efficiencies of 84.32 ± 1.9 % and 15.25 ± 2.4 % respectively. The zein protein interaction with silymarin, and β-cyclodextrin was shown to be beneficial via the use of molecular simulations and binding energy calculations. Cellular studies demonstrated dose and time dependent cytotoxicity of SLNPs on MCF-7 breast cancer cell. FACS, qRT-PCR and Western blotting showed Bax (pro-apoptotic) upregulation while Bcl-2 (anti-apoptotic) downregulation. Our findings suggest that these loaded nanoparticles are more efficient than pure drug, enhancing its bioavailability and paving the path for developing it as a promising nutraceutical to treat breast cancer.

Cigarette smoke-induced galectin-3 as a diagnostic biomarker and therapeutic target in lung tissue remodeling

Galectin-3 (Gal-3), a multifunctional carbohydrate-binding lectin, has emerged as a key player in various biological processes including inflammation, cancer, cardiovascular diseases and fibrotic disorders, however it remains unclear if Gal-3 is a bystander or drives lung tissue remodeling (LTR). Persistent exposure to cigarette smoke (CS) is the leading cause of oxidative and inflammatory damage to the lung tissues. CS-induced pathological increase in Gal-3 expression has been implicated in the pathogenesis of various respiratory conditions, such as chronic obstructive pulmonary disease (COPD), idiopathic pulmonary fibrosis (IPF), and lung cancer. We and others have reported that CS induces Gal-3 synthesis and secretion, which modulates the pathological signaling pathways in lung epithelial cells implicating Gal-3 as a novel diagnostic marker and a factor driving LTR in CS-exposed lungs. Therefore, pharmacological interventions targeting Gal-3 and its upstream and downstream signaling pathways can help combat CS-induced LTR. Excitingly, preclinical models have demonstrated the efficacy of interventions such as Gal-3 expression inhibition, Gal-3 receptor blockade, and signaling pathways modulation open up promising avenues for future therapeutic interventions. Furthermore, targeting extracellular vesicles-mediated Gal-3 release and the potential of microRNA-based therapy are emerging as novel therapeutic approaches in CS-induced LTR and have been discussed in this article.

Enhancing apoptosis-mediated anticancer activity of evodiamine through protein-based nanoparticles in breast cancer cells

In the cutting-edge era of developing precision therapeutics, nanoparticles have emerged as a potent drug delivery system. Altering the size of poorly water-soluble drugs to nanoscale could confer change in their physical properties, including enhanced water solubility and bioavailability. Evodiamine (EVO), a natural indolequinone alkaloid extract from Evodia rutaecarpa, has shown several important pharmacological applications, anti-cancer being one of them. Protein-based nano-drug delivery systems have gained the interest of researchers due to their better biocompatibility, biodegradability, non-immunogenicity and non-toxicity. In the present study, EVO encapsulated BSA nanoparticles (ENPs) were synthesized and characterized, which were nanoscale-sized (~ 150 nm), monodispersed, spherical shaped, and showed high entrapment efficiency (~ 86%) and controlled drug release. The in-vitro anti-cancer activity of ENPs on human breast cancer cells was dose- and time-dependent. The apoptotic molecular mechanism investigated using FACS, qRT-PCR, and western blotting analysis, revealed increased expression of p53 and Bax and decreased expression of Bcl-2. Biological studies demonstrated comparatively more efficient and targeted delivery of ENPs than pure EVO. The comprehensive physiochemical characterization and in-vitro validation collectively pinpoint ENPs as a promising avenue for harnessing the therapeutic potential of the natural anti-cancer compound EVO. The findings indicate improved cytotoxicity, positioning ENPs as a propitious strategy for advancing breast cancer treatment.

Integrating Synthesis, Physicochemical Characterization, and In Silico Studies of Cordycepin-Loaded Bovine Serum Albumin Nanoparticles

Cordycepin gets rapidly metabolized in the body into inactive form due to its structural similarity to adenosine, thus inhibiting its development as a medicinal agent. This study was aimed to improve the solubility and stability of cordycepin, a potential drug with known antiproliferative activity, by encapsulating it in bovine serum albumin: β-cyclodextrin nanoparticles. Cordycepin-loaded nanoparticles (CLNPs) were synthesized using the antisolvent method and characterized thoroughly using various techniques. Our dynamic light scattering measurement showed a particle size and zeta potential of 160 ± 2.75 nm and -20.21 ± 2.1 mV, respectively, for CLNPs. Transmission electron microscopy studies revealed that particles were spherical in morphology. These CLNPs showed sustained release of cordycepin with encapsulation and loading efficiency of 81.62 ± 1.5 and 27.02 ± 2.0%, respectively, based on high-performance liquid chromatography and UV-vis studies. Based on differential scanning calorimetry and zeta potential studies, CLNPs improve cordycepin stability and solubility. Our molecular simulations and binding energy calculation also showed favorable protein interaction between cordycepin, bovine serum albumin, and β-cyclodextrin, further supporting the notion of improved stability. In vitro cytotoxicity, apoptosis, and cellular uptake studies on breast cancer cells showed that the synthesized nanoparticles had greater cytotoxicity as compared to free cordycepin.

Visfatin-induced upregulation of lipogenesis via EGFR/AKT/GSK3β pathway promotes breast cancer cell growth

Breast cancer (BC) incidence and associated mortality have increased in tandem with the growth in obesity among the females worldwide. An adipokine, visfatin, has been shown to potentially impact glucose, lipid, and protein metabolism, and promote cancer growth however, the mechanism underlying the effect of visfatin on lipid metabolism dysregulation contributing to BC cell survival, proliferation, and metastasis has not been elucidated. Herein, we have investigated the role of visfatin on the induction of Sterol regulatory element binding protein (SREBP-1) and its upstream and downstream mediators in MCF-7 breast cancer cells. The survival and proliferation was investigated using MTT and Trypan blue assays, cytosolic lipid accumulation was observed using Nile red staining, mRNA and protein expressions were examined using RT-qPCR and western blotting, respectively, and cell cycle analysis was performed using fluorescence-activated cell sorting. Our results indicate that visfatin increased the survival and proliferation of MCF-7 cells in a time- and dose-dependent manner and augmented lipid buildup via activation of SREBP-1 and its associated downstream lipid synthesizing enzymes, at both mRNA and protein levels in MCF-7 cells. Inhibiting SREBP-1 using fatostatin or silencing with siRNA abrogated excessive lipid deposition by suppressing the expression of genes related to lipid synthesis pathway. Further, in-silico study showed high affinity binding of visfatin with epidermal growth factor receptor (EGFR), which was confirmed in an in-vitro study where visfatin increased the phosphorylation of EGFR at tyrosine residue and activated its downstream proteins via phosphorylation of AKT and GSK3β in MCF-7 cells. Inhibition of GSK3β by phosphorylation led to increased activity of SREBP-1 and associated downstream proteins. In summary, SREBP-1 may be a critical player in visfatin-induced lipid synthesis and accumulation in BC cells via activation of EGFR/AKT/GSK3β pathway leading to increased cell survival and proliferation of BC cells.

Cigarette smoke induces epithelial-to-mesenchymal transition, stemness, and metastasis in lung adenocarcinoma cells via upregulated RUNX-2/galectin-3 pathway

AIMS

An elevated level of galectin-3, a carbohydrate-binding lectin implicated in tumorigenesis, metastasis, and epithelial-mesenchymal transition (EMT), has been found in cigarette smokers. However, the regulation of its expression and role in the pathogenesis of CS-induced EMT and lung cancer metastasis is unclear. Here, we have investigated the mechanism of CS-induced and galectin-3-mediated EMT in airway epithelial cells (AECs).

MAIN METHODS

A549 adenocarcinoma cells and primary small airway epithelial cells cultured on an air-liquid interface (ALI) were exposed to cigarette smoke extract (CSE), and MTT, trypan blue, migration, invasion, tumor spheroid and colony formation assays were performed to assess EMT phenotype. Immunoblotting was performed to assess EMT and stemness markers and other regulatory proteins.

KEY FINDINGS

CSE exposure affected cell survival and morphology, migration, invasion, and clonogenicity of AECs, which were concomitant with an increase in the expression of EMT markers, galectin-3, and runt-related transcription factor-2 (RUNX-2), an osteogenic transcription factor and upstream regulator of galectin-3. Chemical inhibition or silencing of RUNX-2 downregulated galectin-3 and modulated EMT marker expression, migration, invasion, and clonogenicity in CSE-exposed AECs. Recombinant human galectin-3 also induced EMT and stemness-associated changes in the AECs, and GB1107, a galectin-3 inhibitor, ameliorated these changes. Further, CSE-induced intracellular ROS enabled an increase in RUNX-2 and galectin-3 expression, which were reversed by n-acetyl-cysteine.

SIGNIFICANCE

These results provide a novel mechanistic insight into CSE-induced EMT via RUNX-2/galectin-3 axis mediated through ROS, which promoted EMT-associated changes, including invasion, migration, and stemness in AECs, which could be implicated in CS-induced lung cancer progression.

Cellular and molecular insights into the roles of visfatin in breast cancer cells plasticity programs

Obesity has reached a pandemic proportion and is responsible for the augmentation of multimorbidity including certain cancers. With the rise in obesity amongst the female population globally, a concomitant increase in breast cancer (BC) incidence and related mortality has been observed. In the present review, we have elucidated the cellular and molecular insight into the visfatin-mediated cellular plasticity programs such as Epithelial to mesenchymal transition (EMT) and Endothelial to mesenchymal transition (EndoMT), and stemness-associated changes in BC cells. EMT and EndoMT are responsible for inducing metastasis in cancer cells and conferring chemotherapy resistance, immune escape, and infinite growth potential. Visfatin, an obesity-associated adipokine implicated in metabolic syndrome, has emerged as a central player in BC pathogenesis. Several studies have indicated the presence of visfatin in the tumor microenvironment (TME) where it augments EMT and EndoMT of BC cells. Further, Visfatin also modulates the TME by acting on the tumor stroma cells such as adipocytes, infiltrated immune cells, and adipose-associated stem cells that secrete factors such as cytokines, and extracellular vesicles responsible for augmenting cellular plasticity program. Visfatin induced altered metabolism of the cancer cells and molecular determinants such as non-coding RNAs involved in EMT and EndoMT have been discussed. We have also highlighted specific therapeutic targets that can be exploited for the development of effective BC treatment. Taken together, these advanced understandings of cellular and molecular insight into the visfatin-mediated cellular plasticity programs may stimulate the development of better approaches for the prevention and therapy of BC, especially in obese patients.

Air-Liquid Interface Culture Model to Study Lung Cancer-Associated Cellular and Molecular Changes

Airway epithelial cells arrayed in the inner lining of the airways of the lung are believed to be the major source for the development of malignancy of the lung. The advent of in vitro cell culture model made it easy to understand the molecular mechanism of carcinogenesis at a cellular level, where the airway epithelial cells are cultured on a 2D surface submerged in the culture media. However, this method of culturing airway epithelial cells does not reflect their true nature, and thus results obtained have their limitations. Further, they exhibit dissimilar morphology, transcriptome, and secretome when compared to the cells in vivo. Thus, the experimental data obtained from 2D culture models are inconclusive and, in most cases, could not be validated further in in vivo settings. These limitations can be addressed by culturing the airway epithelial cells on air-liquid interface (ALI), where they develop ciliated morphology similar to that of the lung. Experiments performed with this 3D model provide reliable data that are more realistic, and, in many cases, could replace the requirement of further in vivo validation. Here, we provide the detailed protocol of a 3D culture system called ALI culture for growing human-derived primary small airway epithelial cells to study the cellular and molecular changes associated with lung cancer.

Fisetin suppresses cigarette smoke extract-induced epithelial to mesenchymal transition of airway epithelial cells through regulating COX-2/MMPs/β-catenin pathway

Cigarette smoke exposure leads to upregulation of cyclooxygenase-2 (COX-2), an inducible enzyme that synthesizes prostaglandin E2 (PGE2) and promotes airway inflammation. COX-2 overexpression is frequently implicated in inflammation, invasion, metastasis, and epithelial-mesenchymal transition (EMT). However, its detailed molecular mechanism in cigarette smoke induced EMT is not clear. Further, fisetin, a bioflavonoid, exhibits antioxidant and anti-inflammatory properties, but its effect in modulating COX-2-mediated inflammation and downstream sequelae remains unexplored. Therefore, we have investigated the mechanism of cigarette smoke-induced COX-2-mediated EMT in airway epithelial cells and examined the role of fisetin in controlling this aberration. MTT, trypan blue staining, gelatin zymography, Western blotting, invasion, wound healing, and tumor sphere formation assays in cigarette smoke extract (CSE) and/or fisetin treated airway epithelial cells, and in-silico molecular docking studies were performed. Results revealed that CSE exposure increased the expression and activity of COX-2, MMP-2/9, and β-catenin and also enhanced expression of EMT markers leading to higher migration and invasion potential of airway epithelial cells. A specific COX-2 inhibitor NS-398 as well as fisetin treatment reversed the expression of EMT biomarkers, reduced the activity of MMP-2/9, and blocked the migration and invasion potential induced by CSE. Further, PGE2 also increased MMPs activity, invasion, and migration potential similar to CSE, which were significantly reversed by fisetin. In-silico studies showed a high binding affinity of fisetin to key EMT associated proteins, validating its anti-EMT potential. Thus, our study firstly unearths the mechanism of CSE-induced EMT in airway epithelial cells via COX-2/MMP/β-catenin pathway, and secondly, it reveals that fisetin could significantly reverse CSE-induced EMT by inhibiting COX-2, indicating that fisetin could be an effective drug candidate for cigarette smoke-induced lung dysfunction.

Method of Preparation of Cigarette Smoke Extract to Assess Lung Cancer-Associated Changes in Airway Epithelial Cells

Smoking tobacco is a major risk factor for the development of lung cancer, COPD, and other lung pathologies in smokers. Cigarette smoke (CS), which is comprised of several toxic components, is known to cause oxidative stress and inflammation-induced lung damage. Since airway epithelial cells act as the primary barrier, they protect the lung tissues from environmental insults, including CS. Upon exposure to these insults, airway epithelial cells act as the initial site of injury and orchestrate the pathophysiology of lung cancer. Scientists have been using cigarette smoke extract (CSE) in the preclinical model of in vitro cell culture to understand the effect of CS on the cellular, biochemical, and molecular changes in the lung epithelial cells. However, the standard procedure to prepare the CSE in the laboratory with a low-cost assembly and obtaining a reproducible quality of CSE in different batches is a challenge. Here, in this chapter, we delineate the method for the preparation of CSE using a discontinuous puff-based system which is an economical and reproducible method to prepare CSE in the laboratory. This method is suitable for studying CSE-induced molecular changes in lung diseases, including lung cancer, using in vitro models of lung adenocarcinoma cells.

Vaccines and drugs under clinical trials for prevention and treatment of COVID-19

The uncertainty related to prevention and treatment of Coronavirus disease 2019 due to lack of effective vaccine candidates or drug molecules has resulted in extensive spread of infection and mortality worldwide. Although the asymptomatic or mild patients are becoming healthy with regular over-the-counter medicines and proper rest and care, for the severe patients, in the absence of definite cure, different drug combinations are being used to treat on trial basis without the assurance of efficacy and safety. This scenario has however changed now with some medicines including antiviral Remdesivir and Favipiravir and anti-inflammatory drugs like dexamethasone and tocilizumab which have shown some positive results in trials such as decreasing need of mechanical or non-invasive ventilation or mortality. Further, a number of vaccine candidates are currently in pipeline and in advance stages of clinical trials, which will enhance their prospects in determining how the disease will be controlled in the times to come. In this article, an account of the under-trial potential drugs and vaccine candidates has been provided, and their future prospects have been discussed.

COVID-19 severity in obese patients: Potential mechanisms and molecular targets for clinical intervention

With the global spread of SARS-CoV-2, millions of people have been affected leading to the declaration of coronavirus disease 2019 (COVID-19) as a pandemic by the WHO. Several studies have linked the severity of COVID-19 cases and increased fatality in patients with obesity and other comorbid conditions such as diabetes, cardiovascular diseases, hypertension, and kidney disease. Obesity, a metabolically deranged condition, establishes a low-grade chronic inflammation in the body, which affects different organs and promotes the development of several other diseases. The ways in which SARS-CoV-2 infection aggravates the already overloaded body organs with inflammation or vice versa has perplexed the researchers. As a result, there is an intensified search for the clear-cut mechanism to understand the link of obesity with the increased severity of COVID-19 in obese patients. In this article we have discussed various mechanisms linking obesity, inflammation, and COVID-19 to enhance the understanding of the disease process and help the clinicians and scientists develop potential cellular, molecular and metabolic targets for clinical intervention and management of COVID-19 severity in obese patients.

Cysteinyl leukotriene D4 (LTD4) promotes airway epithelial cell inflammation and remodelling

OBJECTIVE

Cysteinyl leukotrienes (CysLTs), a group of inflammatory lipid mediators, are found elevated in obese-asthmatic patients. Leukotriene D4 (LTD4), a representative CysLT, is implicated in promoting lung inflammation and remodelling in allergic asthma, but its role in non-allergic asthma, especially in obese-asthmatic patients, is not known. Here, using primary human small airway epithelial cells (SAECs) we have investigated the mechanism of LTD4-induced inflammation and remodelling and assessed high proneness of obese mice to develop asthma upon challenge with allergen ovalbumin (OVA).

METHODS

Primary human small airway epithelial cells (SAECs) were stimulated with different concentrations of LTD4 for different time intervals and various inflammatory markers were measured through cytokine array, membrane-based ELISA and Western blotting. An air-liquid interface (ALI) model of SAECs was used to study the effects of LTD4-induced remodelling in SAECs using Western blotting, H&E staining and PAS staining. Further, OVA-based murine model was used to examine the propensity of high-fat diet (HFD)-fed obese mice to develop asthma symptoms by studying the infiltration of inflammatory cells (assessed by bronchioalveolar lavage (BAL) cytology) and airway remodelling (assessed by histopathology) upon allergen exposure.

RESULTS

The human primary small airway epithelial cells (SAECs) treated with LTD4 showed significant alterations in the levels of inflammatory markers such as GM-CSF, TNF-α, IL-1β, EGF and eotaxin in dose- and time-dependent manner. Further, LTD4 enhanced the activation of inflammasomes as evidenced by increased levels of NALP3, cleaved caspase-1 and IL-1β. LTD4 also enhanced inflammation by increasing the expression of COX-2 in SAECs. The airway remodelling markers Vimentin and Muc5AC were found elevated in ALI culture of SAECs when stimulated with LTD4, as it also increased TGF-β levels and activation of Smad2/3 phosphorylation in SAECs. Last, sensitization and challenge of HFD-fed obese mice with OVA showed increased infiltration of inflammatory cells in BAL and enhanced levels of remodeling phenotypes like loss of cilia, mucus cell metaplasia and collagen deposition in mice lung tissues.

CONCLUSION

The results suggest that LTD4 could induce inflammatory response in human airway epithelial cell by activating NALP3 inflammasome. LTD4 could further promote airway epithelial cells' remodelling through TGF-β/smad2/3-mediated pathway. Our in vivo results suggested that obesity predisposed the OVA challenged mice to develop lung inflammation and remodelling akin to asthma-like phenotypes during obesity.

Physico-chemical characterization of carvacrol loaded zein nanoparticles for enhanced anticancer activity and investigation of molecular interactions between them by molecular docking

Carvacrol (CV), a monoterpene possesses wide range of biological activities but has limited application due to low aqueous solubility and poor bioavailability. To address this issue and enhance bioavailability and efficacy of carvacrol, lecithin stabilized zein nanoparticles were investigated. Precipitation method was used for synthesis of nanoparticles and characterized using various techniques. CV entrapped under optimized parameters has size around 250 nm with -15 mV zeta potential. SEM studies showed nanoparticles with spherical morphology and size in accordance with DLS studies. FTIR, NMR and DSC were used to determine the molecular interaction between CV and lecithin stabilized zein nanoparticles. Molecular docking studies were performed to understand the interaction between protein and drug at molecular level. Our results demonstrated the presence of two active sites within zein, showing strong binding interactions with carvacrol. The encapsulation efficiency of 78% with loading efficiency of 13% was obtained as per HPLC and UV-Vis studies. Cytotoxicity assay indicated that the CV loaded nanoparticles induce cytotoxicity against colon cancer (SW480) cells further confirmed by acridine orange and ethidium bromide dual staining assay. Fluorescent tagged nanoparticles revealed significant cellular uptake of drug. Our results suggest that CV can be conveniently delivered via oral route after incorporating into lecithin stabilized zein nanoparticles and may prove effective for colon cancer treatment.

Amorphous nano morin outperforms native molecule in anticancer activity and oral bioavailability

In the past decade, naturally occurring phytoconstituents have emerged as potential therapeutic agents and alternative to synthetic drugs. However, efficient delivery of hydrophobic phytoconstituents into the body with desired therapeutic efficacy is a key challenge for the pharmaceutical industries due to their insolubility in water and low oral bioavailability. Nanosuspension formulations have shown promises to improve the delivery of the hydrophobic molecules with simultaneously avoiding the drawbacks like carrier toxicity and scale-up issues of other nanotechnology-based drug delivery systems. In this study, we have used morin hydrate (MH), a flavonol, and developed MH nanosuspension formulation (MHNS) to improve its poor physiochemical properties and low oral bioavailability. Different stabilizers with varying concentrations were investigated for preparing nanosuspension. MHNS was characterized by DLS, TEM, FTIR, DSC, powder XRD and was evaluated for its solubility, dissolution, partition coefficient, in-vitro anticancer activity and pharmacokinetics in rats. The optimized nanosuspension formulation, with a size of <100 nm, is capable of increasing aqueous solubility, dissolution rate, and oral bioavailability of MH. Moreover, the therapeutic efficacy, in terms of cytotoxicity to human lung cancer cells, of MH was also increased after formulating into nanosuspension form.

Dual drug-delivering polycaprolactone-collagen scaffold to induce early osteogenic differentiation and coupled angiogenesis

Bone regeneration is a multi-step, overlapping process, in which angiogenesis and osteogenesis are the key players. Several attempts have been made to promote angiogenesis-coupled osteogenesis using scaffolding technology. However, the recreation of functional vasculature during bone regeneration is an unparalleled challenge. In this study, a dual drug-delivering polycaprolactone-collagen fibrous scaffold is reported to promote early osteogenesis and angiogenesis. Simvastatin as a pro-angiogenic and dexamethasone as an osteoinductive drug were encapsulated to functionalize the electrospun fibers. The optically transparent fibrous mat represented the sustained and sequential release of drugs for 28 days. The fibrous mesh increased cell proliferation and enhanced the osteogenic differentiation up to 21 days. The alkaline phosphatase activity and mineral deposition were comparatively higher on dual drug-releasing fibers when compared to control fibers. The dual drug-releasing osteoconductive fibers demonstrated osteogenesis as early as 7 days with a 3.7 and 1.5 fold increase in the expression of osteogenic differentiation markers (RUNX2 and osteocalcin), respectively. In vitro angiogenesis using primary human umbilical vein endothelial cells (pHUVECs) showed no significant difference in cell proliferation among control fibers and dual drug-releasing fibers. However, the angioinductive nature of simvastatin released from the fibers demonstrated tube formation and 2 fold higher angiogenic score. The mRNA and protein expression study of angiogenic markers (VEGFR2 and eNOS) by polymerase chain reaction and western blotting depicted the angioinducing potential of dual drug-releasing fibers. VEGFR2 and eNOS mRNA expressions increased by 1.1 and 1.6 fold, respectively, whereas their protein expression increased by 3.2 and 1.7 fold, respectively. The overall results demonstrate the synergistic effect of osteoconductive substrate and osteoinductive dual drugs to promote early osteogenesis, and release of the pro-angiogenic drug promotes angiogenesis.

Thermal and microwave synthesized SPIONs: Energy effects on the efficiency of nano drug carriers

Superparamagnetic iron oxide nanoparticles (SPIONs) were optimally synthesized employing two energy sources viz. thermal and microwave using low temperature co-precipitation process. Both methods yielded particles with optimum physicochemical properties for biomedical applications like smaller size (~6--7 nm), narrow size distribution (standard deviation ~1.6-1.7 nm) and good magnetic parameters (saturation magnetisation ~53 emu/g at 9 T). Simplified process made use of domestic oven. After coating by amino acid serine, successful loading (>8 wt%) of drug Doxorubicin was achieved for both SPIONs. Microwave sample showed equivalently efficient drug loading despite half the serine coating. Findings were confirmed by various techniques like X-ray diffraction (XRD), transmission electron microscopy (TEM), Vibrating sample magnetometer (VSM) and thermo gravimetric analysis (TGA) etc. Differences in thermal homogeneities and efficiency of heat transfer between two energy modes affected the properties of synthesized SPIONs. Differences were observed in amount of serine coating, drug release behaviour and in vitro experiments on A549 cells like internalisation and cell viability data. About 59 and 39% pH and time dependent drug release at pH 5 was obtained for thermal and microwave sample respectively. In vitro experiments confirmed the successful internalisation and cell death, supporting the suitability of SPIONS as efficient targeted drug carriers. Despite lesser drug release, microwave sample showed comparable in vitro results. Study emphasizes the role and importance of energy in affecting the efficiency and functional behaviour of SPIONs as nano drug carriers. Being biocompatible and magnetic these particles can be applied successfully as efficient targeted drug delivery agents.

MMP-2 and MMP-9 mediate cigarette smoke extract-induced epithelial-mesenchymal transition in airway epithelial cells via EGFR/Akt/GSK3β/β-catenin pathway: Amelioration by fisetin

Matrix metalloproteinases (MMPs) have been implicated in EMT but their role in the regulation of cigarette smoke-induced EMT in airway epithelium is not clear. We have therefore investigated the potential role of MMP-2 and -9 in cigarette smoke extract (CSE) induced EMT using A549 lung epithelial cells and human small airway epithelial cells (SAEC). The cells were treated with different concentration of CSE, and MTT and trypan blue assays, acridine orange-ethidium bromide assay, gelatin zymography, Western blotting, immunofluorescence studies, Boyden-chamber assay, wound healing assay and air-liquid interface (ALI) culture were used to assess different cellular and molecular changes associated with EMT. The results depict that CSE increased the cytotoxicity along with a concurrent increase in the expression and activity of MMP-2 and -9. CSE further altered EMT markers like E-cadherin, N-cadherin, vimentin, and the molecular modulators of EMT such as β-catenin and pGSK-3β. Further, CSE also upregulated EGFR, AKT, and ERK1/2 in airway epithelial cells. SB-3CT, a known inhibitor of MMP-2 and -9, altered and reversed the expression of markers of EMT and kinases, validating the role of MMP-2 and -9 in CSE-induced EMT. Fisetin, a plant-derived bioflavonoid, also reversed the expression of EMT markers and molecular regulators in a similar fashion as SB-3CT. In summary, this study highlights the role of MMP-2 and -9 in CSE-induced EMT and curate its molecular cascade through EGFR/AKT/ERK/β-catenin axis, which could be restored by MMP-2 and -9 inhibitor and fisetin. Fisetin is hitherto unknown to modulate CSE-induced MMPs activity in airway epithelial cells, and our study suggests its potential role as a therapeutic approach in CSE-induced EMT in lung epithelial cells.

Regulation of oxidized LDL-induced inflammatory process through NLRP3 inflammasome activation by the deubiquitinating enzyme BRCC36

OBJECTIVE

Oxidized Low-Density Lipoprotein (oxLDL) is a well-established pro-inflammatory marker that activates the NLRP3 inflammasome. Ubiquitination plays an important role in modulating the stability and functions of various proteins. BRCC36 is a ubiquitin-modifying enzyme that plays a crucial role in protein stabilization and activation in the cytosol, but its role in OxLDL-induced NLRP3 inflammasome activation is not known. Here, we have investigated the role of deubiquitinating enzyme BRCC36 in regulating NLRP3 inflammasome during oxLDL stimulation.

METHODS

Raw 264.7 murine macrophages were stimulated with oxLDL and effect of BRCC36 deubiquitination activity was assessed by fluorometric assay, and protein expression was assessed by Western blotting. The level of IL-1β measured by ELISA and LDH activity as pyroptotic cell death marker was assessed by fluorometric assay.

RESULTS

The results showed that oxLDL increased the level of NLRP3 in macrophages and also the level of active caspase-1 and IL-1β. It also modulated the expression of deubiquitinating enzymes and caused pyroptotic cell death as indicated by LDH release. Inhibiting the proteasomal activity by MG132 and siRNA-mediated silencing of BRCC36 in macrophages potentially suppressed oxLDL-induced NLRP3 inflammasome activation and IL-1β secretion. Furthermore, the inhibition of proteasomal deubiquitinating activity with specific BRCC36 inhibitor G5 also reduced the inflammatory cell death.

CONCLUSION

Taken together, our study suggests that deubiquitinating enzyme BRCC36 inhibition could potentially suppress oxLDL-induced inflammatory process by inhibiting NLRP3 activation and resultant IL-1β secretion.

Adipokine Visfatin's Role in Pathogenesis of Diabesity and Related Metabolic Derangements

Visfatin is one of the prominent adipokines secreted by adipose tissue. The level of visfatin increases significantly in persons with obesity owing to increased body mass index (BMI). During obesity, the adipocytes, which populate adipose tissue, undergo hypertrophy and hyperplasia and secrete a number of adipocytokines including visfatin. Visfatin, which also acts as an enzyme nicotinamide phosphoribosyl transferase, is one of the prominent adipokines that influence metabolic homeostasis in the body. Visfatin exists in two forms, extracellular and intracellular, and enacts a multitude of actions. The direct and indirect evidence gathered from in-vitro, in-vivo and clinical studies indicate that visfatin modulates obesity and metabolic syndrome-related pathophysiological activities including enhanced inflammation, angiogenesis, synthesis of NAD mononucleotide, and upregulation of antiapoptotic proteins in a number of cell types. It has been implicated in a number of obesity-related alterations and metabolic derangement such as diabetes, cardiovascular complications and some forms of cancers. In this review, the novel hypothesis about the role of visfatin in diabesity has been proposed which implies recent advances in studies about the pathophysiological roles of visfatin during obesity and chronic high glucose in the circulation. Visfatin at high concentration attracts immune cells and produces chronic inflammation in adipocytes. Additionally, it induces insulin resistance in many tissues and causes pancreatic beta cells dysfunction at later stages. Further, its potential as an important target to develop molecular medicine in diabesity and related metabolic syndrome has been highlighted.

Endotoxin-Induced Uveitis in Rodents

Uveitis can affect individuals of all ages, genders, and races and accounts for 10-15% of all cases of blindness. Uveitis represents a diverse array of intraocular inflammatory conditions that can be associated with complications from autoimmune diseases, bacterial infections, viral infections, chemical injuries, and metabolic issues. In rodents, endotoxin-induced uveitis (EIU) is an efficient experimental model to study pathological mechanisms associated with the disease and evaluate the pharmacological efficacy of potential new drug agents. In the EIU model, uveitis is characterized by clinically relevant inflammation, including inflammatory exudates and cells infiltrated into the anterior and vitreous eye chambers. EIU in small animal models, including rats, mice, and rabbits, is characterized by a short-lived uveal inflammation. This inflammation can be facilitated using bacterial endotoxins, such as lipopolysaccharide (LPS). In this chapter, we present a reliable, reproducible, and simplified protocol to induce EIU in mice. This method is flexible and can be applied for EIU induction in other small animals and rodents.

Designing of fatty acid-surfactant conjugate based nanomicelles of morin hydrate for simultaneously enhancing anticancer activity and oral bioavailability

Morin hydrate (MH) is a naturally occurring polyphenolic flavonol compound. It has been recently investigated for its many biological activities such as anti-inflammatory, anticancer, antioxidant, antiarthritic, antifertility, antiplasmodic and anticancer. Though these outcomes are very promising, its low aqueous solubility and oral bioavailability restrict its clinical uses. Therefore, in this study we report pluronic F68 and stearic acid conjugated (F68-SA) nanomicelles for increasing oral bioavailability of MH. The MH loaded F68-SA nanomicelles (MHNM) were prepared by the solvent evaporation method. The MHNM were extensively characterized for the size, surface charge, stability, morphology, critical micelle concentration, drug content, and in-vitro drug release. The cell viability assay depicted a significant increase in cytotoxicity of MH against A549 human lung cancer cells after incubating as MHNM. Exposure of A549 cells to MHNM induced cell apoptosis in the cells as observed in apoptosis studies. Pharmacokinetic studies in Sprague-Dawley rats revealed that MHNM significantly increased the oral bioavailability of MH as compared to pure drug. Therefore, the novel, surfactant-lipid based micellar system is an effective solubilizing and delivering system for oral administration of poorly water soluble drugs like MH.

Sterol regulatory element binding protein (SREBP) -1 mediates oxidized low-density lipoprotein (oxLDL) induced macrophage foam cell formation through NLRP3 inflammasome activation

Macrophage foam cell formation (FCF) has long been known to play a critical role during atherosclerotic plaque development. In the presence of atherogenic molecules such as oxidized low-density lipoprotein (oxLDL) macrophages accumulate massive amounts of lipid through uptake. However, in the presence of oxLDL mechanism of dysregulated lipid homeostasis in the macrophages remains largely unknown. Herein we have investigated the role of Sterol regulatory element binding protein (SREBP)-1 in oxLDL-induced inflammation and altered lipid homeostasis in macrophages. The U937 monocytes and monocyte-derived macrophages (MDMs) were stimulated with different doses of oxLDL. MTT assay to study the effect of oxLDL on cell viability, Oil-Red-O (ORO) staining to observe cytosolic lipid accumulation, semi-quantitative PCR and Western blotting to analyze mRNA and protein expressions, respectively, and spectrophotometric assay to measure the lipid synthesizing enzyme's activity were performed. Our results indicate that oxLDL increased proliferation in monocytes and decreased the viability in MDMs in a time- and dose-dependent manner. The oxLDL (100 μg/ml) enhanced lipid accumulation via increased expressions of SREBP-1 and its downstream proteins such as fatty acid synthase (FAS) and 3-hydroxy-3-methylglutaryl-CoA reductase (HMGCR) at both RNA and protein levels in monocytes as well as in MDMs. Inhibiting SREBP-1 by a synthetic inhibitor prevented excessive lipid accumulation by downregulating the expression of its downstream proteins. Further, oxLDL increased reactive oxygen species (ROS) levels, NLRP3 inflammasome activation and active interleukin 1β (IL-1β) release in both the cell types. The oxLDL-induced NLRP3 could be responsible for SREBP-1 and downstream proteins overexpression as siRNA silencing of NLRP3 decreased SERBP-1 levels. In summary, we have demonstrated that SREBP-1 could be a key player in oxLDL-induced excessive lipid accumulation leading to macrophage FCF via ROS-mediated NLRP3/IL-1β/SREBP-1 pathway.

Lupeol induces S-phase arrest and mitochondria-mediated apoptosis in cervical cancer cells

Cervical cancer is fourth most common fatal cancer in women worldwide. Lupeol is a dietary triterpenoid and has shown its anticancer efficacy against various cancer types with selectivity in targeting cancer cells. In the present study, anticancer efficacy and mechanism of action of a phytochemical, lupeol, in human cervical carcinoma (HeLa) cells has been examined. The anticancer efficacy of lupeol was assessed by trypan blue cell counting, annexin Vassay, cell cycle analysis, expression of apoptotic proteins by RT-PCR and Western blotting and assessment of mitochondrial ROS generation by mitosox and mitotracker assays. Our results demonstrated that lupeol decreased cell proliferation and viability of HeLa cells significantly (p less than 0.001). Lupeol induced S-phase cell cycle arrest and also decreased the expression of S-phase Cyclins and CDKs and increased the expression of cyclin-dependent kinase inhibitors, p21 at transcriptional and translational level. Further, lupeol induced apoptosis and increased the expression of apoptosis markers such as cleaved PARP and Bax:Bcl-2 ratio. Furthermore, mitosox and mitotracker dye incubation followed by FACS analysis showed an increase in mitochondrial superoxide generation and reduction in healthy mitochondrial mass. These results suggest that lupeol could be an effective chemotherapeutic agent against cervical carcinoma due to its growth inhibitory activity through induction of S-phase cell cycle arrest and apoptosis.

Novel Insights in the Metabolic Syndrome-induced Oxidative Stress and Inflammation-mediated Atherosclerosis

Context:

Atherosclerosis is a progressive pathological process and a leading cause of mor-tality worldwide. Clinical research and epidemiological studies state that atherosclerosis is caused by an amalgamation of metabolic and inflammatory deregulation involving three important pathological events including Endothelial Dysfunction (ED), Foam Cell Formation (FCF), and Vascular Smooth Muscle Cells (VSMCs) proliferation and migration.

Objectives:

Research in recent years has identified Metabolic Syndrome (MS), which involves factors such as obesity, insulin resistance, dyslipidemia and diabetes, to be responsible for the pathophysiol-ogy of atherosclerosis. These factors elevate oxidative stress and inflammation-induced key signalling molecules and various microRNAs (miRs). In present study, we have reviewed recently identified molecular targets in the pathophysiology of atherosclerosis.

Methods:

Scientific literature obtained from databases such as university library, PubMed and Google along with evidences from published experimental work in relevant journals has been sum-marized in this review article.

Results:

The molecular events and cell signalling implicated in atherogenic processes of ED, FCF and VSMCs hyperplasia are sequential and progressive, and involve cross talks at many levels. Specific molecules such as transcription factors, inflammatory cytokines and chemokines and miRs have been identified playing crucial role in most of the events leading to atherosclerosis.

Conclusion:

Studies associated with MS induced oxidative stress- and inflammation- mediated sig-nalling pathways along with critical miRs help in better understanding of the pathophysiology of ath-erosclerosis. Several key molecules discussed in this review could be potent target for the prevention and treatment of atherosclerosis.

Lipid mediator Leukotriene D4-induces airway epithelial cells proliferation through EGFR/ERK1/2 pathway

BACKGROUND

Cysteinyl leukotrienes (CysLTs), the potent lipid inflammatory mediators, are elevated in many pathological conditions and implicated in various inflammatory diseases including asthma, however their role in airway epithelial cells modulation is not clearly understood. We have investigated the effects of a CysLT, Leukotriene D₄ (LTD₄) on human airway epithelial cells, and assessed its role and mode of action in these cells.

METHODOLOGY

Human small airway epithelial cells (SAECs) and A549 cells were incubated with different concentrations of LTD₄ for different time intervals. Subsequently trypan blue dye exclusion assay, MTT assay, Western blotting, RT-PCR and immunofluorescence experiments were performed to examine the effects of LTD₄ on proliferation and related molecular changes in the airway epithelial cells.

RESULTS

The treatment of human airway epithelial cells with LTD₄ resulted in a significant increase in cell proliferation and modulation in the expression of receptors, CysLT₁R and CysLT₂R in SAECs as well as A549 cells. In both types of cells, LTD₄ increased the expression levels of PCNA and c-myc, and trans-activated EGF receptor and increased the activation of ERK1/2. When treated along with epidermal growth factor (EGF), LTD₄ showed a marginal additive effect in ERK1/2 and EGFR phosphorylation compared to LTD₄ alone in both types of airway epithelial cells.

CONCLUSION

In conclusion, these results suggest that sustained presence of lipid inflammatory mediator LTD₄ could induce human airway epithelial cell proliferation through ERK1/2 phosphorylation, either directly via CysLT₁ receptor or by transactivating EGFR.

Cysteinyl Leukotrienes (CysLTs): Role in Obesity-Induced Asthma

Epidemiological studies associate obesity with onset of asthma, especially in obese children, suggesting obesity as the risk factor for asthma. Obesity-induced chronic inflammation has been implicated in the lung inflammation, yet specific mediators and mechanisms are lacking. Obesity is associated with increased expression of 5-lipoxygenase (5-LO) pathway and increased Leukotrienes (LTs) production has been observed in obese asthma patients. However, the precise mechanism that predisposes lungs inflammation in obese is not clearly understood. This article discusses the production and regulation of LTs in obese individuals and presents probable mechanisms regarding the role of LTs in lung inflammation that may lead to obesity-induced asthma. Leukotrienes are well known mediators of asthma but their role in obesity-induced asthma is not clearly understood and thus needs further research. Since efficient antagonists and inhibitors of 5-LO pathways are known, understanding of molecular mechanism of LTs, especially Cysteinyl-LTs, in obesity-induced asthma could lead to optimal treatment regimens for the prevention and treatment of asthma in obese individuals.

Oxidative stress and metabolic disorders: Pathogenesis and therapeutic strategies

Increased body weight and metabolic disorder including insulin resistance, type 2 diabetes and cardiovascular complications together constitute metabolic syndrome. The pathogenesis of metabolic syndrome involves multitude of factors. A number of studies however indicate, with some conformity, that oxidative stress along with chronic inflammatory condition pave the way for the development of metabolic diseases. Oxidative stress, a state of lost balance between the oxidative and anti-oxidative systems of the cells and tissues, results in the over production of oxidative free radicals and reactive oxygen species (ROS). Excessive ROS generated could attack the cellular proteins, lipids and nucleic acids leading to cellular dysfunction including loss of energy metabolism, altered cell signalling and cell cycle control, genetic mutations, altered cellular transport mechanisms and overall decreased biological activity, immune activation and inflammation. In addition, nutritional stress such as that caused by high fat high carbohydrate diet also promotes oxidative stress as evident by increased lipid peroxidation products, protein carbonylation, and decreased antioxidant system and reduced glutathione (GSH) levels. These changes lead to initiation of pathogenic milieu and development of several chronic diseases. Studies suggest that in obese person oxidative stress and chronic inflammation are the important underlying factors that lead to development of pathologies such as carcinogenesis, obesity, diabetes, and cardiovascular diseases through altered cellular and nuclear mechanisms, including impaired DNA damage repair and cell cycle regulation. Here we discuss the aspects of metabolic disorders-induced oxidative stress in major pathological conditions and strategies for their prevention and therapy.

Cell-death assessment by fluorescent and nonfluorescent cytosolic and nuclear staining techniques

Apoptosis, a genetically programmed cellular event leads to biochemical and morphological changes in cells. Alterations in DNA caused by several factors affect nucleus and ultimately the entire cell leading to compromised function of the organ and organism. DNA, a master regulator of the cellular events, is an important biomolecule with regards to cell growth, cell death, cell migration and cell differentiation. It is therefore imperative to develop the staining techniques that may lead to visualize the changes in nucleus where DNA is housed, to comprehend the cellular pathophysiology. Over the years a number of nuclear staining techniques such as propidium iodide, Hoechst-33342, 4', 6-diamidino-2-phenylindole (DAPI), Acridine orange-Ethidium bromide staining, among others have been developed to assess the changes in DNA. Some nonnuclear staining techniques such as Annexin-V staining, which although does not stain DNA, but helps to identify the events that result from DNA alteration and leads to initiation of apoptotic cell death. In this review, we have briefly discussed some of the most commonly used fluorescent and nonfluorescent staining techniques that identify apoptotic changes in cell, DNA and the nucleus. These techniques help in differentiating several cellular and nuclear phenotypes that result from DNA damage and have been identified as specific to necrosis or early and late apoptosis as well as scores of other nuclear deformities occurring inside the cells.

Prevention of allergic rhinitis by aldose reductase inhibition in a murine model

BACKGROUND

Allergic rhinitis, one of the most common atopic diseases, is known to be elicited by Th2 cytokine-mediated inflammatory response. We have shown earlier that a polyol pathway enzyme aldose reductase (AR) regulates airway inflammation; however its role in allergic rhinitis is not known. We have investigated the role of AR in mediating pathological symptoms associated with allergic rhinitis in mice.

METHODS

The wild-type (WT) mice treated without or with AR inhibitor and AR knock out (AR(-/-)) mice were sensitized by two intraperitoneal injections of ragweed pollen extract (RWE) with adjuvant alum on days 0 and 4 followed by challenge on day 11 and/or 18 and 25. The allergic rhinitis symptoms were assessed by monitoring the nasal scratch, mast cell degranulation and release of tryptase in nasal lavage, infiltration of inflammatory cells, production of inflammatory cytokines and nasal epithelium remodeling.

RESULTS

Sensitization and challenge of mice with RWE produced robust and reproducible pathological symptoms of allergic rhinitis as compared to control mice. AR inhibitor, fidarestat administered mice showed markedly reduced early phase response to allergen exposure such as nasal scratches, mast cells degranulation and release of tryptase in the nasal passage as well as late phase response such as inflammatory cell infiltration and release of Th2 type cytokines and nasal epithelial remodeling. Further, prevention of these events in AR(-/-)) mice suggests the role of AR in the mediation of allergic rhinitis.

CONCLUSION

These results indicate an important role of AR in the mediation of RWE-induced allergic rhinitis in mice and prevention by AR inhibitor, fidarestat offers a novel therapeutic approach to ameliorate allergic rhinitis.

Pharmacological effects of Trigonella foenum-graecum L. in health and disease

CONTEXT

The health benefits and medicinal properties of herbal food products are known since antiquity. Fenugreek [Trigonella foenum-graecum Linn. (Fabaceae)], a seed spice used to enhance flavor, color and texture of food, is employed for medicinal purposes in many traditional systems. A number of epidemiological studies and laboratory research have unraveled the biological actions of fenugreek.

OBJECTIVE

Research on fenugreek in recent years has identified a number of health benefits and physiological attributes in both experimental animals as well as clinical trials in humans. In this study we have reviewed the available scientific literature on fenugreek.

METHODS

This review article summarizes and reviews published experimental studies and scientific literature from the databases including PubMed, Google and local library searches.

RESULTS

The information available in the literature on the health benefits and pharmaceutical effects of Trigonella accounts for its known medicinal properties and adds new therapeutic effects in newer indications. Besides its known medicinal properties such as carminative, gastric stimulant, antidiabetic and galactogogue (lactation-inducer) effects, newer research has identified hypocholesterolemic, antilipidemia, antioxidant, hepatoprotective, anti-inflammatory, antibacterial, antifungal, antiulcer, antilithigenic, anticarcinogenic and other miscellaneous medicinal effects of fenugreek. Although most of these studies have used whole seed powder or different forms of extracts, some have identified active constituents from seeds and attributed them medicinal values for different indications.

CONCLUSION

The resarch on Trigonella exhibits its health benefits and potential medicinal properties in various indications and has little or no side effects, suggesting its pharmaceutical, therapeutic and nutritional potential.

Aldose reductase regulates acrolein-induced cytotoxicity in human small airway epithelial cells

Aldose reductase (AR), a glucose-metabolizing enzyme, reduces lipid aldehydes and their glutathione conjugates with more than 1000-fold efficiency (Km aldehydes 5-30 µM) relative to glucose. Acrolein, a major endogenous lipid peroxidation product as well as a component of environmental pollutants and cigarette smoke, is known to be involved in various pathologies including atherosclerosis, airway inflammation, COPD, and age-related disorders, but the mechanism of acrolein-induced cytotoxicity is not clearly understood. We have investigated the role of AR in acrolein-induced cytotoxicity in primary human small airway epithelial cells (SAECs). Exposure of SAECs to varying concentrations of acrolein caused cell death in a concentration- and time-dependent manner. AR inhibition by fidarestat prevented the low-dose (5-10 µM) but not the high-dose (>10 µM) acrolein-induced SAEC death. AR inhibition protected SAECs from low-dose (5 µM) acrolein-induced cellular reactive oxygen species (ROS). Inhibition of acrolein-induced apoptosis by fidarestat was confirmed by decreased condensation of nuclear chromatin, DNA fragmentation, comet tail moment, and annexin V fluorescence. Further, fidarestat inhibited acrolein-induced translocation of the proapoptotic proteins Bax and Bad from the cytosol to the mitochondria and that of Bcl2 and BclXL from the mitochondria to the cytosol. Acrolein-induced cytochrome c release from mitochondria was also prevented by AR inhibition. The mitogen-activated protein kinases (MAPKs), such as extracellular signal-regulated kinases 1 and 2, stress-activated protein kinase/c-Jun NH2-terminal kinase, and p38MAPK, and c-Jun were transiently activated in airway epithelial cells by acrolein in a concentration- and time-dependent fashion, which was significantly prevented by AR inhibition. These results suggest that AR inhibitors could prevent acrolein-induced cytotoxicity in the lung epithelial cells.

Aldose reductase inhibition prevents allergic airway remodeling through PI3K/AKT/GSK3β pathway in mice

BACKGROUND

Long-term and unresolved airway inflammation and airway remodeling, characteristic features of chronic asthma, if not treated could lead to permanent structural changes in the airways. Aldose reductase (AR), an aldo-sugar and lipid aldehyde metabolizing enzyme, mediates allergen-induced airway inflammation in mice, but its role in the airway remodeling is not known. In the present study, we have examined the role of AR on airway remodeling using ovalbumin (OVA)-induced chronic asthma mouse model and cultured human primary airway epithelial cells (SAECs) and mouse lung fibroblasts (mLFs).

METHODS

Airway remodeling in chronic asthma model was established in mice sensitized and challenged twice a week with OVA for 6 weeks. AR inhibitor, fidarestat, was administered orally in drinking water after first challenge. Inflammatory cells infiltration in the lungs and goblet cell metaplasia, airway thickening, collagen deposition and airway hyper-responsiveness (AHR) in response to increasing doses of methacholine were assessed. The TGFβ1-induced epithelial-mesenchymal transition (EMT) in SAECs and changes in mLFs were examined to investigate AR-mediated molecular mechanism(s) of airway remodeling.

RESULTS

In the OVA-exposed mice for 6 wks inflammatory cells infiltration, levels of inflammatory cytokines and chemokines, goblet cell metaplasia, collagen deposition and AHR were significantly decreased by treatment with AR inhibitor, fidarestat. Further, inhibition of AR prevented TGFβ1-induced altered expression of E-cadherin, Vimentin, Occludin, and MMP-2 in SAECs, and alpha-smooth muscle actin and fibronectin in mLFs. Further, in SAECs, AR inhibition prevented TGFβ1- induced activation of PI3K/AKT/GSK3β pathway but not the phosphorylation of Smad2/3.

CONCLUSION

Our results demonstrate that allergen-induced airway remodeling is mediated by AR and its inhibition blocks the progression of remodeling via inhibiting TGFβ1-induced Smad-independent and PI3K/AKT/GSK3β-dependent pathway.

Endotoxin-induced uveitis in rodents

Uveitis is a common cause of vision loss, accounting for 10-15 % of all cases of blindness worldwide and affects individuals of all ages, genders, and races. Uveitis represents a broad range of intraocular inflammatory conditions due to complications of autoimmune diseases, bacterial infections, viral infections, and chemical and metabolic injuries. Endotoxin-induced uveitis (EIU) in rodents is an efficient experimental model to investigate the pathological mechanism and pharmacological efficacy of potential drug agents. EIU is characterized by clinically relevant classical signs of inflammation, including inflammatory exudates and cells in the anterior and vitreous chambers. EIU in small animal models such as rats, mice, and rabbits is a short-lived uveal inflammation that can be developed subsequent to administration of bacterial endotoxin, such as lipopolysaccharide. Here, we present a reproducible, reliable, and simplified protocol to induce EIU in mice. This method could be used with similar efficacy for EIU induction in other small animals as well.

Current prospective of aldose reductase inhibition in the therapy of allergic airway inflammation in asthma

The prevalence of asthma and costs of its care have been continuously increasing, but novel therapeutic options to treat this inflammatory disease have not been brought to the US market. Current therapies such as inhaled steroids, long-acting beta-agonist bronchodilators, antihistamines and immunomodulators may control the symptoms of allergic asthma but fail to modify the underlying disease. Excessive use of steroids and other immunosuppresents alter the patient's quality of life, produce undesirable toxicities, and increase the risk of other pathologies such as diabetes. Hence novel therapeutic options to manage asthma are desirable. In the present review, we have discussed the role of the polyol pathway enzyme aldose reductase (AR) in the amplification of allergic airway inflammation. Recent studies have indicated that AR inhibition prevents the NF-κB-dependent generation of pro-inflammatory cytokines and chemokines in mouse models of allergic airway inflammation indicating the potential use of AR inhibition as a novel tool to control allergic responses. Since orally available AR inhibitors have already undergone phase III clinical trials for diabetic neuropathy and appear to have a manageable side effects profile, they could be readily developed as potential new drugs for the treatment of asthma and related complications.

Aldose reductase deficiency in mice protects from ragweed pollen extract (RWE)-induced allergic asthma

Background

Childhood hospitalization related to asthma remains at historically high levels, and its incidence is on the rise world-wide. Previously, we have demonstrated that aldose reductase (AR), a regulatory enzyme of polyol pathway, is a major mediator of allergen-induced asthma pathogenesis in mouse models. Here, using AR null (AR^-/-) mice we have investigated the effect of AR deficiency on the pathogenesis of ragweed pollen extract (RWE)-induced allergic asthma in mice and also examined the efficacy of enteral administration of highly specific AR inhibitor, fidarestat.

Methods

The wild type (WT) and AR^-/- mice were sensitized and challenged with RWE to induce allergic asthma. AR inhibitor, fidarestat was administered orally. Airway hyper-responsiveness was measured in unrestrained animals using whole body plethysmography. Mucin levels and Th2 cytokine in broncho-alveolar lavage (BAL) were determined using mouse anti-Muc5A/C ELISA kit and multiplex cytokine array, respectively. Eosinophils infiltration and goblet cells were assessed by H&E and periodic acid Schiff (PAS)-staining of formalin-fixed, paraffin-embedded lung sections. T regulatory cells were assessed in spleen derived CD4⁺CD25⁺ T cells population.

Results

Deficiency of AR in mice led to significantly decreased PENH, a marker of airway hyper-responsiveness, metaplasia of airway epithelial cells and mucus hyper-secretion following RWE-challenge. This was accompanied by a dramatic decrease in infiltration of eosinophils into sub-epithelium of lung as well as in BAL and release of Th2 cytokines in response to RWE-challenge of AR^-/- mice. Further, enteral administration of fidarestat significantly prevented eosinophils infiltration, airway hyper-responsiveness and also markedly increased population of T regulatory (CD4⁺CD25⁺FoxP3⁺) cells as compared to RWE-sensitized and challenged mice not treated with fidarestat.

Conclusion

Our results using AR^-/- mice strongly suggest the role of AR in allergic asthma pathogenesis and effectiveness of oral administration of AR inhibitor in RWE-induced asthma in mice supports the use of AR inhibitors in the treatment of allergic asthma.

Aldose reductase deficiency protects from autoimmune- and endotoxin-induced uveitis in mice

PURPOSE

To investigate the effect of aldose reductase (AR) deficiency in protecting the chronic experimental autoimmune (EAU) and acute endotoxin-induced uveitis (EIU) in c57BL/6 mice.

METHODS

The WT and AR-null (ARKO) mice were immunized with human interphotoreceptor retinoid-binding peptide (hIRPB-1-20), to induce EAU, or were injected subcutaneously with lipopolysaccharide (LPS; 100 μg) to induce EIU. The mice were killed on day 21 for EAU and at 24 hours for EIU, when the disease was at its peak, and the eyes were immediately enucleated for histologic and biochemical studies. Spleen-derived T-lymphocytes were used to study the antigen-specific immune response in vitro and in vivo.

RESULTS

In WT-EAU mice, severe damage to the retinal wall, especially to the photoreceptor layer was observed, corresponding to a pathologic score of ∼2, which was significantly prevented in the ARKO or AR inhibitor-treated mice. The levels of cytokines and chemokines increased markedly in the whole-eye homogenates of WT-EAU mice, but not in ARKO-EAU mice. Further, expression of inflammatory marker proteins such as inducible nitric oxide synthase (iNOS), cyclooxygenase (COX)-2, tumor necrosis factor (TNF)-α, and vascular cell adhesion molecule (VCAM)-1 was increased in the WT-EIU mouse eyes but not in the ARKO-EIU eyes. The T cells proliferated vigorously when exposed to the hIRPB antigen in vitro and secreted various cytokines and chemokines, which were significantly inhibited in the T cells isolated from the ARKO mice.

CONCLUSIONS

These findings suggest that AR-deficiency/inhibition protects against acute as well as chronic forms of ocular inflammatory complications such as uveitis.

Amelioration of experimental autoimmune uveoretinitis by aldose reductase inhibition in Lewis rats

PURPOSE

Recently, the authors showed that the inhibition of aldose reductase (AR) prevents bacterial endotoxin-induced uveitis in rats. They have now investigated the efficacy of AR inhibitors in the prevention of experimental autoimmune-induced uveitis (EAU) in rats.

METHODS

Lewis rats were immunized with bovine interphotoreceptor retinoid-binding peptide (IRBP) to develop EAU. Two or 8 days after immunization, the rats started receiving the AR inhibitor fidarestat (7 mg/kg/d; intraperitoneally). They were killed when the disease was at its peak; aqueous humor (AqH) was collected from one eye, and the other eye of each rat was used for histologic studies. The protein concentration and the levels of inflammatory markers were determined in AqH. Immunohistochemical analysis of eye sections was performed to determine the expression of inflammatory markers. The effect of AR inhibition on immune response was investigated in isolated T lymphocytes.

RESULTS

Immunization of rats by IRBP peptide resulted in a significant infiltration of leukocytes in the posterior and the anterior chambers of the eye. Further, EAU caused an increase in the concentration of proteins, inflammatory cytokines, and chemokines in AqH, and the expression of inflammatory markers such as inducible-nitric oxide synthase and cycloxygenase-2 in the rat eye ciliary bodies and retina. Treatment with fidarestat significantly prevented the EAU-induced ocular inflammatory changes. AR inhibition also prevented the proliferation of spleen-derived T cells isolated from EAU rats in response to the IRBP antigen.

CONCLUSIONS

These results suggest that AR could be a novel mediator of bovine IRBP-induced uveitis in rats.

Aldose reductase inhibition suppresses airway inflammation

Airway inflammation induced by reactive oxygen species (ROS)-mediated activation of redox-sensitive transcription factors is the hallmark of asthma, a prevalent chronic respiratory disease. In various cellular and animal models, we have recently demonstrated that, in response to multiple stimuli, aldose reductase (AKR1B1) regulates the inflammatory signals via NF-kappa B activation. Since NF-κB activation is implicated in asthma pathogenesis, we investigated whether AKR1B1 inhibition could prevent ovalbumin (Ova)- and ragweed pollen extract (RWE)-induced airway inflammation and hyper-responsiveness in mice models and tumor necrosis factor-alpha (TNF-α)-, lipopolysachharide (LPS)- and RWE-induced cytotoxic and inflammatory signals in primary human small airway epithelial cells (SAEC). Sensitization and challenge with Ova or RWE caused airway inflammation and production of inflammatory cytokines, accumulation of eosinophils in airways and sub-epithelial regions, mucin production in the bronchoalveolar lavage fluid, airway hyperresponsiveness, elevated IgE levels and release of Th2 cytokines in the airway and treatment with AKR1B1 inhibitors markedly reduced these pathological changes in mice. In SAEC, treatment with TNF-α, LPS or RWE induced apoptosis, reactive oxygen species generation, synthesis of inflammatory markers IL-6, IL-8, and PGE2 and activation of NF-κB and AP-1. Pharmacological inhibition prevented these changes suggesting that AKR1B1 mediates ROS induced inflammation in small airway epithelial cells. Our results indicate that AKR1B1 inhibitors may offer a novel therapeutic approach to treat inflammatory airway diseases such as asthma.

Emerging role of antioxidants in the protection of uveitis complications

Current understanding of the role of oxidative stress in ocular inflammatory diseases indicates that antioxidant therapy may be important to optimize the treatment. Recently investigated antioxidant therapies for ocular inflammatory diseases include various vitamins, plant products and reactive oxygen species scavengers. Oxidative stress plays a causative role in both non-infectious and infectious uveitis complications, and novel strategies to diminish tissue damage and dysfunction with antioxidant therapy may ameliorate visual complications. Preclinical studies with experimental animals and cultured cells demonstrate significant anti-inflammatory effects of a number of promising antioxidant agents. Many of these antioxidants are under clinical trial for various inflammatory diseases other than uveitis such as cardiovascular, rheumatoid arthritis and cancer. Well planned interventional clinical studies in the field of ocular inflammation will be necessary to sufficiently investigate the potential medical benefits of antioxidant therapies for uveitis. This review summarizes the recent investigations of novel antioxidant agents for ocular inflammation, with selected studies focused on uveitis.

Understanding the role of aldose reductase in ocular inflammation

Aldose reductase, although identified initially as a glucose-reducing enzyme via polyol pathway, is believed to be an important component of antioxidant defense system as well as a key mediator of oxidative stress-induced molecular signaling. The dual role played by AR has made it a very important enzyme for the regulation of not only the cellular redox state by detoxifying the reactive lipid-aldehydes generated by lipid peroxidation which is crucial in the cellular homeostasis, but also in the regulation of molecular signaling cascade that may regulate oxidative stress-induced cytotoxic events. Search for the new molecular targets to restrain the oxidative stress-induced inflammation has resulted in the identification of AR as an unanticipated mediator of oxidative stress-induced signaling. Although, in last one decade or so AR has been implicated in various inflammation-related diseases conditions ranging from diabetes, sepsis, cancer, cardiovascular and ocular inflammation, however, a critical evaluation of the clinical efficacy of AR inhibitors awaits a better understanding of the role of AR in regulating inflammation, especially in ocular inflammation.

Protective role of benfotiamine, a fat-soluble vitamin B1 analogue, in lipopolysaccharide-induced cytotoxic signals in murine macrophages

This study was designed to investigate the molecular mechanisms by which benfotiamine, a lipid-soluble analogue of vitamin B1, affects lipopolysaccharide (LPS)-induced inflammatory signals leading to cytotoxicity in the mouse macrophage cell line RAW264.7. Benfotiamine prevented LPS-induced apoptosis, expression of the Bcl-2 family of proapoptotic proteins, caspase-3 activation, and PARP cleavage and altered mitochondrial membrane potential and release of cytochrome c and apoptosis-inducing factor and phosphorylation and subsequent activation of p38-MAPK, stress-activated kinases (SAPK/JNK), protein kinase C, and cytoplasmic phospholipase A2 in RAW cells. Further, phosphorylation and degradation of inhibitory kappaB and consequent activation and nuclear translocation of the redox-sensitive transcription factor NF-kappaB were significantly prevented by benfotiamine. The LPS-induced increased expression of cytokines and chemokines and the inflammatory marker proteins iNOS and COX-2 and their metabolic products NO and PGE(2) was also blocked significantly. Thus, our results elucidate the molecular mechanism of the anti-inflammatory action of benfotiamine in LPS-induced inflammation in murine macrophages. Benfotiamine suppresses oxidative stress-induced NF-kappaB activation and prevents bacterial endotoxin-induced inflammation, indicating that vitamin B1 supplementation could be beneficial in the treatment of inflammatory diseases.

Inhibition of aldose reductase attenuates endotoxin signals in human non-pigmented ciliary epithelial cells

Chronic inflammatory diseases such as autoimmune and bacterial infections are associated with an elevated risk of ocular inflammation. Ciliary epithelial cells that play an important role in maintaining aqueous humor dynamics and homeostasis of anterior segment of eye are continuously exposed to inflammatory markers during infections and injury. Lipopolysacchharide (LPS), a Gram-negative bacterial endotoxin, dysregulates aqueous humor (AqH) homeostasis by inducing inflammatory changes. We have investigated how inhibition of a polyol pathway enzyme, aldose reductase (AR), alters LPS-induced inflammatory changes in human non-pigmented ciliary epithelial cells (hNPECs). The stimulation of hNPECs with LPS (1 microg/ml) caused increased secretion of inflammatory markers such as PGE(2) and NO in the culture medium as well as increased expression of COX-2 and iNOS proteins in cell extracts. LPS also increased phosphorylation of MAPKs (ERK1/2) and SAPK/JNK and activation of redox-sensitive transcription factors NF-kappaB and AP-1 in hNPECs and inhibition of AR by zopolrestat and sorbinil ameliorated these changes. Further, LPS-induced decrease in the expression of Na/K-ATPase in hNPECs was restored by AR inhibitors. Similar results were observed in ciliary bodies of LPS-injected rats. Taken together, our results suggest that AR plays an important role in the LPS-induced inflammatory changes in hNPECs and that inhibition of AR could be a novel therapeutic approach for ocular inflammation.

Protective effects of magnesium lithospermate B against diabetic atherosclerosis via Nrf2-ARE-NQO1 transcriptional pathway

Hyperglycemia-induced oxidative stress is known to play an important role in the development of several diabetic complications, including atherosclerosis. Although a number of antioxidants are available, none have been found to be suitable for regulating the oxidative stress response and enhancing antioxidative defense mechanisms. In this study, we evaluated the effects of magnesium lithospermate B (LAB) against oxidative stress. We also endeavored to identify the target molecule of LAB in vascular smooth muscle cells (VSMCs) and the underlying biochemical pathways related to diabetic atherosclerosis. Modified MTT and transwell assays showed that the increased proliferation and migration of rat aortic VSMCs in culture with high glucose was significantly inhibited by LAB. LAB also attenuated neointimal hyperplasia after balloon catheter injury in diabetic rat carotid arteries. To determine molecular targets of LAB, we studied the effects of LAB on aldose reductase (AR) activity, O-GlcNAcylation, and protein kinase C (PKC) activity in VSMCs under normoglycemic or hyperglycemic conditions and showed the improvement of major biochemical pathways by LAB. Potential involvement of the nuclear factor erythroid 2-related factor-2 (Nrf2)--antioxidant responsive element (ARE)-NAD(P)H: quinone oxidoreductase-1 (NQO1) pathway was assessed using siRNA methods. We found that LAB activates the NQO1 via the Nrf2-ARE pathway, which plays an important role in inhibition of the major molecular mechanisms that lead to vascular damage and the proliferation and migration of VSMCs. Together, these findings demonstrate that the induction of the Nrf2-ARE-NQO1 pathway by LAB could be a new therapeutic strategy to prevent diabetic atherosclerosis.

Aldose reductase inhibition suppresses the expression of Th2 cytokines and airway inflammation in ovalbumin-induced asthma in mice

Airway inflammation induced by reactive oxygen species-mediated activation of redox-sensitive transcription factors is the hallmark of asthma, a prevalent chronic respiratory disease. In various cellular and animal models, we have recently demonstrated that, in response to multiple stimuli, aldose reductase (AR) regulates the inflammatory signals mediated by NF-kappaB. Because NF-kappaB-mediated inflammation is a major characteristic of asthma pathogenesis, we have investigated the effect of AR inhibition on NF-kappaB and various inflammatory markers in cellular and animal models of asthma using primary human small airway epithelial cells and OVA-sensitized/challenged C57BL/6 mice, respectively. We observed that pharmacological inhibition or genetic ablation of AR by small interfering RNA prevented TNF-alpha- as well as LPS-induced apoptosis; reactive oxygen species generation; synthesis of inflammatory markers IL-6, IL-8, and PGE(2); and activation of NF-kappaB and AP-1 in small airway epithelial cells. In OVA-challenged mice, we observed that administration of an AR inhibitor markedly reduced airway hyperresponsiveness, IgE levels, eisonophils infiltration, and release of Th2 type cytokines in the airway. Our results indicate that AR inhibitors may offer a novel therapeutic approach to treat inflammatory airway diseases such as asthma.

Prevention of endotoxin-induced uveitis in rats by benfotiamine, a lipophilic analogue of vitamin B1

PURPOSE

To study the amelioration of ocular inflammation in endotoxin-induced uveitis (EIU) in rats by benfotiamine, a lipid-soluble analogue of thiamine.

METHODS

EIU in Lewis rats was induced by subcutaneous injection of lipopolysaccharide (LPS) followed by treatment with benfotiamine. The rats were killed 3 or 24 hours after LPS injection, eyes were enucleated, aqueous humor (AqH) was collected, and the number of infiltrating cells, protein concentration, and inflammatory marker levels were determined. Immunohistochemical analysis of eye sections was performed to determine the expression of inducible-nitric oxide synthase (iNOS), cyclooxygenase (Cox)-2, protein kinase C (PKC), and transcription factor NF-kappaB.

RESULTS

Infiltrating leukocytes, protein concentrations, and inflammatory cytokines and chemokines were significantly elevated in the AqH of EIU rats compared with control rats, and benfotiamine treatment suppressed these increases. Similarly increased expression of inflammatory markers iNOS and Cox-2 in ciliary body and retinal wall was also significantly inhibited by benfotiamine. The increased phosphorylation of PKC and the activation of NF-kappaB in the ciliary body and in the retinal wall of EIU rat eyes were suppressed by benfotiamine.

CONCLUSIONS

These results suggest that benfotiamine suppresses oxidative stress-induced NF-kappaB-dependent inflammatory signaling leading to uveitis. Therefore, benfotiamine could be used as a novel therapeutic agent for the treatment of ocular inflammation, especially uveitis.

Prevention of posterior capsular opacification through aldose reductase inhibition

PURPOSE

The purpose of this study was to evaluate the effect of aldose reductase (AR) inhibition on posterior capsular opacification (PCO) with the use of a pig eye capsular bag model.

METHODS

Pig eye capsular bags were prepared by capsulorhexis and cultured in medium without or with AR inhibitors for 7 days. Immunostaining was performed in paraformaldehyde-fixed capsular bags to determine the expression of proliferating cell nuclear antigen (PCNA), alpha-smooth muscle actin (SMA), beta-crystallin, and intercellular adhesion molecule (ICAM)-1. The effect of AR inhibition on basic fibroblast growth factor (BFGF)-induced mitogenic signaling in cultured human lens epithelial cells (HLECs) was examined. Cell growth was assessed by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl tetrazolium bromide (MTT) assay and cell counting, the expression of alpha-SMA, beta-crystallin, and ICAM-1 by Western blot and immunocytochemical analysis, protein kinases by Western blot analysis, and NF-kappaB activation by gel shift and reporter assays.

RESULTS

During culture of pig eye capsular bags, residual cells on both the anterior and the posterior capsule showed vigorous growth. Treatment with AR inhibitors significantly prevented the lens epithelial cell growth in capsular bags and expression of alpha-SMA, beta-crystallin, and ICAM-1. HLECs showed a dose-dependent response to BFGF, proliferation at lower concentrations (<20 ng/mL) and differentiation/transdifferentiation at higher concentrations (>50 ng/mL). Inhibition of AR also prevented the BFGF-induced activation of ERK1/2, JNK, and NF-kappaB in HLECs.

CONCLUSIONS

Results suggest that AR is required for lens epithelial cell growth and differentiation/transdifferentiation in the capsular bags, indicating that inhibition of AR could be a potential therapeutic target in the prevention of PCO.