Ferulic acid's therapeutic odyssey: nano formulations, pre-clinical investigations, and patent perspective.

INTRODUCTION: Ferulic acid (FA) is a phenolic phytochemical that has garnered the attention of the research community due to its abundant availability in nature. It is a compound that has been explored for its multifaceted therapeutic potential and benefits in modern and contemporary healthcare. AREAS COVERED: This review furnishes a compilation of the molecular mechanisms underlying the anti-diabetic, anticancer, antioxidant, and anti-inflammatory effects of FA. We also aim to excavate an in-depth analysis of the role of nanoformulations to achieve release control, reduce toxicity, and deliver FA at specified target sites. To corroborate the safety and efficacy of FA, a multitude of pre-clinical studies have also been conducted by researchers and have been discussed comprehensively in this review. The various patented innovations and newer paradigms pertaining to FA have also been presented. EXPERT OPINION: Enormous research has been conducted and should still be continued to find the best possible novel drug delivery system for FA delivery. The utilization of nanocarriers and nanoformulations has intrigued the scientists for delivery of FA, but before that, it is necessary to shed light upon toxicity, safety, and regulatory concerns of FA.

Diethylene glycol monoethyl ether-mediated nanostructured lipid carriers enhance trans-ferulic acid delivery by Caco-2 cells superior to solid lipid nanoparticles.

This work aimed to compare the performance of trans-ferulic acid-encapsulated nanostructured lipid carriers (NLCs) and solid lipid nanoparticles (SLNs) for transport by Caco-2 cells. The NLC particles (diameter: 102.6 nm) composed of Compritol® 888 ATO, ethyl oleate, Cremophor® EL, and Transcutol® P were larger than the SLNs (diameter: 86.0 nm) formed without liquid lipid (ethyl oleate), and the former had a higher encapsulation efficiency for trans-ferulic acid (p < 0.05). In vitro cultured Caco-2 cell transport was used to simulate intestinal absorption, and the cellular uptake of NLCs was higher than that of SLNs (p < 0.05). Compared to SLNs, NLCs greatly enhanced trans-ferulic acid permeation through the MillicellTM membrane (p < 0.05). This work confirms that NLCs have better properties than SLNs in terms of increasing drug transport by Caco-2 cells. This helps to comprehend the approach by which NLC-mediated oral bioavailability of trans-ferulic acid is better than that mediated by SLNs, as shown in our previous report.

An UHPLC/LC-MS illustrated the dynamic profiling of balanophorin B, gallic acid, and 4-hydroxycinnamic acid in rat as 3 molecular entities from Balanophora simaoensis.

An UHPLC/LC-MS was founded to detect balanophorin B (B), gallic acid (GA), 4-hydroxycinnamic acid (HC), and their in vivo profiling in rats, after oral administration of the ethanol extract of Balanophora simaoensis S. Y. Chang et Tam. The in vivo dynamic existence of 3 molecular entities in rats and the multistep biotransformation of GA were elucidated by their sensitive mass spectrometry response after efficient UHPLC and/or HPLC separation, through analyzing the bio-samples of rat plasma, bile, liver, kidneys, and excreta. The method was validated with satisfactory calibration curves having correlation coefficients r from 0.996 to 0.999 for concentration scaled from 0.100 nM to 0.100 µM, internal standard normalized matrix factors ranged from 0.923 to 0.993, sextuplicate recoveries valued from 95.0% to 103.6%, as well as accuracy and precision varied from 95.6% to 103.7%. The content of B, GA, and HC in the whole herb was of 4.66, 63.5, and 10.4 µmol/kg in dry weight, respectively. The Cmax for B, GA, and HC in rat systemic circulation was of 76.0 nM, 2.30 µM, and 51.0 µM, with tmax at 3, 2, and 2 h, respectively. B and GA stayed in rat liver over 4 hs to present a material base for the pharmacology and pharmacodynamics of the whole herb. The biotransformation of GA indicated a complicated scheme in rats. As a final metabolite from GA with total biotransformation conversion over 20%, 4-hydroxybenzaldehyde resourced from two steps of dehydroxylation and one step of reduction of GA, but not concerned with HC.

Sinapic acid ameliorates cardiac dysfunction and cardiomyopathy by modulating NF-κB and Nrf2/HO-1 signaling pathways in streptozocin induced diabetic rats.

Hyperglycemia and hyperlipidemia-arbitrated mitochondrial oxidative insult is key reason for cardiac dysfunction and cardiomyopathy. Sinapic acid (SA) is a hydroxycinnamic acid (a polyphenolic acid) present in multiple plants and possesses several pharmacological activities. In this study, we examined the cardio protective effects of SA on streptozotocin (STZ)-induced cardiac insults. STZ and both STZ induced diabetes and normal control rats were administered with 20 and 40 mg/kg SA for 12 weeks. STZ rats demonstrated hyperglycemia and hyperlipidemia. Additionally, STZ administered rats exhibited various histological changes in the cardiac muscles and significantly enhanced CK-MB and LDH. The significant enhancement of oxidative stress, inflammation, and apoptotic markers, and the capacity to curb oxidative stress was significantly abridged in the STZ induced diabetic heart. Chronic treatment with SA (20-40 mg/kg) ameliorated the increased level of glucose, lipid, and cardiac function markers and curtailed histological changes in the cardiac muscles. Chronic treatment also repressed inflammation, oxidative stress and apoptosis thereby and restoring antioxidant defenses in the myocardium of STZ induced diabetic rats. STZ induced cardiac dysfunction and cardiomyopathy by promoting inflammation and oxidative stress. Sinapic acid ameliorates cardiac dysfunction and cardiomyopathy via improvement of hyperglycemia, hyperlipidemia, inflammation, oxidative stress, and apoptosis. Thus, SA possesses possible therapeutic value for the prevention of diabetic cardiac dysfunction and cardiomyopathy via the NRF2/HO-1 and NF-κB pathways.

Ferulic acid-loaded nanocapsules: Evaluation of mucosal interaction, safety and antioxidant activity in human mononucleated cells.

Ferulic acid (FA) is a phenolic compound that has antioxidant, anti-inflammatory and anticarcinogenic properties besides presenting cytoprotective activity. It has limited oral bioavailability what is a challenge to its therapeutic application. In this way, this investigation aimed to develop FA-loaded nanocapsule suspensions (NC-FA) prepared with ethylcellulose and evaluate their in vitro release profile, mucoadhesion and irritation potential; scavenging capacity, cytotoxicity, cytoprotection and genoprotection against hydrogen peroxide-induced damage in hMNC (human Mononucleated Cells) culture. The nanocapsules presented physicochemical characteristics compatible with colloidal systems (NC-FA: 112 ± 3 nm; NC-B (without FA): 107 ± 3 nm; PdI < 0.2; Span<2.0 and negative zeta potential). In addition, the nanoparticulate system promoted the FA controlled release, increasing the half-life twice through the in vitro dialysis method. NC-FA and NC-B were able to interact with mucin, which is an indicative of mucoadhesive properties and the association of FA with nanocapsules showed decreased irritation by HET-CAM method. Besides, the NC-FA did not present cytotoxicity in hMNC and improved the ATBS radical scavenging capacity. Besides, it prevented, treated and reversed oxidative conditions in a H2O2-induced model in hMNC. Thus, this nanocarrier formulation is promising to perform more preclinical investigations focusing on diseases involving oxidative mechanisms.

Salvianolic acid B and ferulic acid synergistically promote angiogenesis in HUVECs and zebrafish via regulating VEGF signaling.

ETHNOPHARMACOLOGICAL RELEVANCE: Induced vascular growth in the myocardium has been widely acknowledged as a promising intervention strategy for patients with ischemic coronary artery disease. Yet despite long-term efforts on gene, protein or cell-based pro-angiogenic therapies, the clinical translation remains challenging. Noticeably, multiple medicinal herbs have long-term documented effects in promoting blood circulation. Salvia miltiorrhiza and Ligusticum stratum are two representative traditional Chinese medicine herbs with suggested roles in enhancing organ blood supply, and Guanxinning Tablet (GXNT), a botanical drug which is formulated with these two herbs, exhibited significant efficacy against angina pectoris in clinical practices. AIM OF THE STUDY: This study aimed to examine the pro-angiogenic activity of GXNT and its major components, as well as to explore their pharmacological mechanism in promoting angiogenesis. MATERIALS AND METHODS: In vitro, the pro-angiogenic effects of GXNT and its major components were examined on human umbilical vein endothelial cells by 3-(4,5-dimethyl-2-thiazolyl)-2,5-diphenyl-2-H-tetrazolium bromide (MTT), scratch assay, and endothelial cell tube formation assay. In vivo, the pro-angiogenic effects were examined on the ponatinib-induced angiogenesis defective zebrafish model. The active compounds were identified through phenotype-based screening in zebrafish, and their pharmacological mechanism was explored in both in vitro and in vivo models by immunofluorescent staining, cell cycle analysis, quantitative PCR and whole embryo in-situ hybridization. RESULTS: We demonstrated strong pro-angiogenic effects of GXNT in both human umbilical vein endothelial cells and zebrafish model. Moreover, through phenotype-based screening in zebrafish for active compounds, pro-angiogenic effects was discovered for salvianolic acid B (Sal B), a major component of Salvia miltiorrhiza, and its activity was further enhanced when co-administered with ferulic acid (FA), which is contained in Ligusticum stratum. On the cellular level, Sal B and FA cotreatment increased endothelial cell proliferation of sprouting arterial intersomitic vessels in zebrafish, as well as largely restored G1-S cell cycle progression and cyclin D1 expression in angiogenic defective HUVECs. Through quantitative transcriptional analysis, increased expression of vegfr2 (kdr, kdrl) and vegfr1 was detected after GXNT or SalB/FA treatment, together with upregulated transcription of their ligands including vegf-a, vegf-b, and pgfb. Bevacizumab, an anti-human VEGF-A monoclonal antibody, was able to significantly, but not completely, block the pro-angiogenic effects of GXNT or SalB/FA, suggesting their multi-targeting properties. CONCLUSIONS: In conclusion, from a traditional Chinese medicine with effects in enhancing blood circulation, we demonstrated the synergistic pro-angiogenic effects of Sal B and FA via both in vitro and in vivo models, which function at least partially through regulating the expression of VEGF receptors and ligands. Future studies are warranted to further elaborate the molecular interaction between these two compounds and the key regulators in the process of neovascularization.

Oral coniferyl ferulate attenuated depression symptoms in mice via reshaping gut microbiota and microbial metabolism.

The gut microbiome is known to be involved in depression development. Thus, phytochemicals changing gut microbiota may alleviate depression-like behaviors. Coniferyl ferulate (CF) is a long studied natural product and known to alleviate psychiatric disorders. However, its mechanism of action remains unclear. In this experimental study, oral administration of 50 mg kg-1 CF once daily attenuated weight loss and depression-like and anxiety-like behaviors induced by chronic unpredicted mild stress (CUMS) in mice. Four weeks of CF administration significantly ameliorated colonic inflammation, lowered the levels of IL-6, IL-1ß, and TNF-α, and restructured the gut microbiome, and microbial metabolism. Intestinal microbiota can impact the development and function of the brain via the microbiota-gut-brain axis. Therefore, oral administration of CF is a promising nutritional strategy to treat CUMS-induced depression via the regulation of microbiota and microbial metabolism.

Hypolipidemic and reduced nitrergic effects of p-hydroxycinnamic diesters extracted from Copernicia prunifera in mice challenged by a high-fat diet.

Dyslipidemia is a chronic non-transmissible condition that has increased due to an unhealthy lifestyle. Statins have been used as the standard treatment to control hyperlipidemia. However, side effects and high costs may be associated with its prolonged treatment, so plants derivatives have been an attractive therapy to overcome these problems. Among the compounds extracted from plants, the p-hydroxycinnamic diesters (HCE), present in carnauba wax (CW), have been found with good pharmacological properties. Therefore, this study aimed to evaluate the potential anti-hypercholesterolemic and possible toxicological effects of HCE in C57BL/6J mice under a high-fat (HF) diet. Male C57BL/6J mice were fed during 60 days under the HF diet and therefore were either treated with HCE (200 and 400 mg/kg) or simvastatin (20 mg/kg) or received saline (controls) by gavage for 30 days under the same diet. HCE treatment was able to reduce serum total cholesterol and LDL levels. Besides, this compound increased liver X receptor (LXR) and but not significantly affected IL-1ß and TNF-α liver mRNA transcription activity. In conclusion, HCE treatment was found safe and may attenuate the deleterious effects of dyslipidemia due to chronic feeding with western diets.

Combined treatment of sinapic acid and ellagic acid attenuates hyperglycemia in streptozotocin-induced diabetic rats.

In the present study, we aimed to investigate the effect of individual and combined treatment of sinapic acid (SA) and ellagic acid (EA) in streptozotocin (STZ)-induced diabetic rats. Rats were divided into eight groups (n = 7): Normal Control, Diabetic Control, Diabetic + Sinapic Acid, Diabetic + Ellagic Acid, Diabetic + Sinapic Acid + Ellagic Acid, Sinapic Acid, Ellagic Acid and Sinapic Acid + Ellagic Acid. Diabetic groups were injected with a single dose of 50 mg/kg STZ intraperitoneally. Rats received 20 mg/kg/day SA and 50 mg/kg/day EA intragastrically for 28 days. The numerical density of immunopositive ß-cells and volume density of pancreatic islets were calculated. Additionally, glucose and insulin levels in serum, MDA, GSH, and CAT levels of pancreatic tissue were measured. While serum glucose levels increased, serum insulin levels decreased in STZ-induced diabetic rats. But these changes in glucose and insulin were restored by individual and combined treatments of SA and EA. Also, individual and combined treatments of SA and EA increased insulin expression of ß-cells in STZ-induced diabetic rats. Moreover, these compounds improved deteriorating oxidative stress parameters in STZ-induced diabetic rats. Our study indicates that SA and EA, especially their combined treatments, can be used as an antihyperglycemic agent in diabetes.

Ferulic Acid Supplementation Increases Lifespan and Stress Resistance via Insulin/IGF-1 Signaling Pathway in C. elegans.

Ferulic acid (FA) is a naturally-occurring well-known potent antioxidant and free radical scavenger. FA supplementation is an effective strategy to delay aging, but the underlying mechanism remains unknown. In the present study, we examined the effects of FA on lifespan extension and its mechanism of FA in Caenorhabditis elegans (C. elegans). Results suggested that FA increased the lifespan of C. elegans, rather than altering the growth of E. coli OP50. Meanwhile, FA promoted the healthspan of C. elegans by improving locomotion and reducing fat accumulation and polyQ aggregation. FA increased the resistance to heat and oxidative stress through reducing ROS. The upregulating of the expression of the hlh-30, skn-1, and hsf-1 were involved in the FA-mediated lifespan extension. Furthermore, FA treatment had no impact on the lifespan of daf-2, hlh-30, skn-1, and hsf-1 mutants, confirming that insulin/IGF-1 signaling pathway and multiple longevity mechanisms were associated with the longevity mechanism of FA. We further found that mitochondrial signaling pathway was modulation involved in FA-mediated lifespan extension. With the results from RNA-seq results and mutants lifespan assay. These findings contribute to our knowledge of the lifespan extension and underlying mechanism of action of FA in C. elegans.

Ferulic Acid Ameliorates Alzheimer's Disease-like Pathology and Repairs Cognitive Decline by Preventing Capillary Hypofunction in APP/PS1 Mice.

Brain capillaries are crucial for cognitive functions by supplying oxygen and other nutrients to and removing metabolic wastes from the brain. Recent studies have demonstrated that constriction of brain capillaries is triggered by beta-amyloid (Aß) oligomers via endothelin-1 (ET1)-mediated action on the ET1 receptor A (ETRA), potentially exacerbating Aß plaque deposition, the primary pathophysiology of Alzheimer's disease (AD). However, direct evidence is still lacking whether changes in brain capillaries are causally involved in the pathophysiology of AD. Using APP/PS1 mouse model of AD (AD mice) relative to age-matched negative littermates, we identified that reductions of density and diameter of hippocampal capillaries occurred from 4 to 7 months old while Aß plaque deposition and spatial memory deficit developed at 7 months old. Notably, the injection of ET1 into the hippocampus induced early Aß plaque deposition at 5 months old in AD mice. Conversely, treatment of ferulic acid against the ETRA to counteract the ET1-mediated vasoconstriction for 30 days prevented reductions of density and diameter of hippocampal capillaries as well as ameliorated Aß plaque deposition and spatial memory deficit at 7 months old in AD mice. Thus, these data suggest that reductions of density and diameter of hippocampal capillaries are crucial for initiating Aß plaque deposition and spatial memory deficit at the early stages, implicating the development of new therapies for halting or curing memory decline in AD.

Mitigation of arsenic induced developmental cardiotoxicity by ferulic acid in zebrafish.

We investigated whether ferulic acid (FA), a nutraceutical could mitigate the arsenic (As) induced cardiotoxicity. Zebrafish larvae (60 and 72 h post-fertilization [hpf]) were used to study the effect of FA on As at different time points (24 and 48 h after exposure). The FA exposure was given as pre-treatment (60 hpf) and simultaneous treatment (72 hpf) to translate the results for As contaminated areas. To accomplish this, the lethality assay was done, and based on the results, the dosage for As (1 mM) and FA (30 µM) was fixed. The FA intervention (30 µM) as 12 h pre-treatment (60 hpf) and simultaneous treatment along with As (72 hpf) decreased the As content in zebrafish larvae as evidenced by inductively coupled plasma-mass spectrometry. As exposure showed congenital deformities especially cardiac malformations in zebrafish larvae after 24 and 48 h. These teratogenic effects induced by As were reduced by FA supplementation in both groups. Also, o-dianisidine staining demonstrated that As treated larvae encountered abnormal cardiac function with reduced blood circulation, while FA supplementation reversed these effects. The acetylcholinesterase activity, a biomarker of As-induced cardiotoxicity was also found to be decreased in As group, which was rescued by FA. The modulation in the expression of the genes involved in cardiogenesis (nkx2.5, bmp2b, gata4, gata5, myh6, myl7, and tnnt2) further confirmed the ameliorative effect of FA on As induced malformations.

Local administration of p-coumaric acid decreases lipopolysaccharide-induced acute lung injury in mice: In vitro and in silico studies.

Acute lung injury (ALI) remains to cause a high rate of mortality in critically ill patients. It is known that inflammation is a key factor in the pathogenesis of lipopolysaccharide (LPS)-induced ALI, which makes it a relevant approach to the treatment of ALI. In this study, we evaluated the potential of nasally instilled p-coumaric acid to prevent LPS-induced ALI in mice, by evaluating its effects on cellular and molecular targets involved in inflammatory response via in vitro and in silico approaches. Our results demonstrated that p-coumaric acid reduced both neutrophil accumulation and pro-inflammatory cytokine abundance, and simultaneously increased IL-10 production at the site of inflammation, potentially contributing to protection against LPS-induced ALI in mice. In the in vitro experiments, we observed inhibitory effects of p-coumaric acid against IL-6 and IL-8 production in stimulated A549 cells, as well as reactive oxygen species generation by neutrophils. In addition, p-coumaric acid treatment decreased neutrophil adhesion on the TNF-α-stimulated endothelial cells. According to the in silico predictions, p-coumaric acid reached stable interactions with both the ATP-binding site of IKKß as well as the regions within LFA-1, critical for interaction with ICAM-1, thereby suppressing the production of proinflammatory mediators and hindering the neutrophil infiltration, respectively. Collectively, these findings indicate that p-coumaric acid is a promising anti-inflammatory agent that can be used for developing a pharmaceutical drug for the treatment of ALI and other inflammatory disorders.

Effects of dietary ferulic acid supplementation on growth performance and skeletal muscle fiber type conversion in weaned piglets.

BACKGROUND: Ferulic acid (FA) is a common polyphenolic compound. The purpose of this study was to explore the effect of dietary FA supplementation on growth performance and muscle fiber type conversion in weaned piglets. In this study, eighteen 21-day-old DLY (Duroc × Landrace × Yorkshire) weaned piglets were randomly divided into control, 0.05% FA, and 0.45% FA groups. RESULTS: Our study showed that dietary FA supplementation had no effect on growth performance, but it could upregulate the expression of slow myosin heavy chain (MyHC) protein, increase the activities of succinic dehydrogenase and malate dehydrogenase, and downregulate the expression of fast MyHC protein. Dietary FA supplementation also increased the expression levels of phosphorylated AMP-activated protein kinase, sirtuin 1 (Sirt1), peroxisome proliferator-activated receptor gamma coactivator 1-alpha (PGC-1α), myocyte enhancer factor 2C, and troponin I-SS, increased the proportion of slow-twitch fiber, and decreased the proportion of fast-twitch fiber. In addition, our results showed that dietary FA supplementation increased the messenger RNA abundance of mitochondrial nuclear transcription genes, including ATP synthase membrane subunit c locus 1, cytochrome oxidase subunit 1, nuclear respiratory factor 1, mitochondrial transcription factor A, mitochondrial transcription factor B1, and cytochrome c. CONCLUSION: We provided the first evidence that FA could promote muscle fiber type conversion from fast-twitch to slow-twitch via the Sirt1/AMP-activated protein kinase/PGC-1α signaling pathway and could improve the mitochondrial function in weaned piglets. This means that FA can be used as a dietary supplement to improve the quality of pork. © 2021 Society of Chemical Industry.

Use of combined nanocarrier system based on chitosan nanoparticles and phospholipids complex for improved delivery of ferulic acid.

A novel nanocarrier system of phospholipids complex loaded chitosan nanoparticles (FAPLC CNPs) was developed to improve the oral bioavailability and antioxidant potential of FA. FAPLC CNPs were optimized using a Box-Behnken Design (BBD). FAPLC CNPs were characterized using differential scanning calorimetry, Fourier transforms infrared spectroscopy, powder x-ray diffractometry, proton nuclear magnetic resonance, solubility, in vitro dissolution, ex vivo permeation, and in vivo antioxidant activity in carbon tetrachloride (CCl4)-induced albino rat model. The characterization studies indicated a formation of the complex as well as FAPLC CNPs. The FAPLC CNPs exhibited a lower particle size ~123.27 nm, PDI value ~0.31, and positive zeta potential ~32 mV respectively. Functional characterization studies revealed a significant improvement in the aqueous solubility, dissolution, and permeation rate of FAPLC and FAPLC CNPs compared to FA and FA CNPs. The FAPLC CNPs showed significant enhancement of in vivo antioxidant activity of FA by restoring the elevated marker enzymes in the CCl4-intoxicated rat model compared to FA CNPs. Moreover, the pharmacokinetic analysis demonstrated a significant enhancement of oral bioavailability of FA from FAPLC CNPs compared to FA CNPs. These findings show that FAPLC CNPs could be used as an effective nanocarrier for improving the oral delivery of FA.

Free ferulic acid supplementation of heat-stressed hair ewe lambs: Oxidative status, feedlot performance, carcass traits and meat quality.

Twenty-two Katahdin × Dorper ewe lambs (average weight = 23.5 ± 2.8 kg) were individually housed during a 40-d feeding study and then slaughtered to evaluate effects of free ferulic acid (FA; 0 and 250 mg/kg of feed) on oxidative status, feedlot growth, carcass and non-carcass traits, wholesale cut yields and meat quality under heat stress conditions. Overall feeding FA decreased protein oxidation without affecting oxidative stress index, while growth rate and feed efficiency increased only in the hottest period (i.e., 28 to 45 °C). The FA supplementation increased kidney-pelvic-heart and mesenteric fat deposition, as well as yields of forequarter, shoulder, ribs, loin, and breast and flank, but decreased yields of hindquarter, neck, plain loin and leg. Carcass characteristics and meat quality were unaffected by FA. Overall, FA supplementation of heat-stressed hair ewe lambs enhanced feedlot performance under extreme heat stress and increased internal fat reserves, while changing muscle mass deposition, possibly because it prevented protein oxidation.

Comprehensive dietary evaluation of Italian primary school children: food consumption and intake of energy, nutrients and phenolic compounds.

Information on children's diet including bioactive compounds is quite scarce. This observational study investigated the composition of the diet of children living in Parma (Italy; n = 172, 8-10 years) using 3-day food records completed in winter and spring. Mean daily intakes of food groups, energy and nutrients were obtained using the national food database, while (poly)phenol contents were estimated from Phenol-Explorer or by specific literature searches. Food consumption, energy and nutrient intakes decreased in spring and were partially in line with national data. Adherence to the nutritional recommendations was not satisfied for the majority of nutrients. Main contributors to the phenolic intake were flavonoids (flavan-3-ols) and phenolic acids (hydroxycinnamic acids), while main dietary sources were fruit, chocolate-based products, vegetables, and tea & coffee (decaffeinated). This study provided the first comprehensive analysis of the nutritional composition of children's diet. Future research should look at the health implications of dietary choices in children.

Hydroxycinnamic Acid from Corncob and Its Structural Analogues Inhibit Aß40 Fibrillation and Attenuate Aß40-Induced Cytotoxicity.

The aggregation of amyloid-ß protein (Aß) is deemed a vital pathological feature of Alzheimer's disease (AD). Hence, inhibiting Aß aggregation is noticed as a major tactic for the prevention and therapy of AD. Hydroxycinnamic acid, as a natural phenolic compound, is widely present in plant foods and has several biological activities including anti-inflammation, antioxidation, and neuroprotective effects. Here, it was found that hydroxycinnamic acid and its structural analogues (3-hydroxycinnamic acid, 2-hydroxycinnamic acid, cinnamic acid, 3,4-dihydroxycinnamic acid, 2,4-dihydroxycinnamic acid, and 3,4,5-trihydroxycinnamic acid) could inhibit Aß40 fibrillogenesis and reduce Aß40-induced cytotoxicity in a dose-dependent manner. Among these small molecules investigated, 3,4,5-trihydroxycinnamic acid is considered to be the most effective inhibitor, which reduces the ThT fluorescence intensity to 30.79% and increases cell viability from 49.47 to 84.78% at 200 µM. Also, the results with Caenorhabditis elegans verified that these small molecules can ameliorate AD-like symptoms of worm paralysis. Moreover, molecular docking studies showed that these small molecules interact with the Aß40 mainly via hydrogen bonding. These results suggest that hydroxycinnamic acid and its structural analogues could inhibit Aß40 fibrillogenesis and the inhibition activity is enhanced with the increase of phenolic hydroxyl groups of inhibitors. These small molecules have huge potential to be developed into novel aggregation inhibitors in neurodegenerative disorders.

In Vitro and In Vivo Efficacy of AZD3965 and Alpha-Cyano-4-Hydroxycinnamic Acid in the Murine 4T1 Breast Tumor Model.

Monocarboxylate transporter 1 (MCT1) represents a potential therapeutic target in cancer. The objective of this study was to determine the efficacy of AZD3965 (a specific inhibitor of MCT1) and α-cyano-4-hydroxycinnamic acid (CHC, a nonspecific inhibitor of MCTs) in the murine 4T1 tumor model of triple-negative breast cancer (TNBC). Expression of MCT1 and MCT4 in 4T1 and mouse mammary epithelial cells were determined by Western blot. Inhibition of MCT1-mediated L-lactate uptake and cellular proliferation by AZD3965 and CHC was determined. Mice bearing 4T1 breast tumors were treated with AZD3965 100 mg/kg i.p. twice-daily or CHC 200 mg/kg i.p. once-daily. Tumor growth, metastasis, intra-tumor lactate concentration, immune function, tumor MCT expression, and concentration-effect relationships were determined. AZD3965 and CHC inhibited cell growth and L-lactate uptake in 4T1 cells. AZD3965 treatment resulted in trough plasma and tumor concentrations of 29.1 ± 13.9 and 1670 ± 946 nM, respectively. AZD3965 decreased the tumor proliferation biomarker Ki67 expression, increased intra-tumor lactate concentration, and decreased tumor volume, although tumor weight was not different from untreated controls. CHC had no effect on tumor volume and weight, or intra-tumor lactate concentration. AZD3965 treatment reduced the blood leukocyte count and spleen weight and increased lung metastasis, while CHC did not. These findings indicate AZD3965 is a potent MCT1 inhibitor that accumulates to high concentrations in 4T1 xenograft tumors, where it increases tumor lactate concentrations and produces beneficial effects on markers of TNBC; however, overall effects on tumor growth were minimal and lung metastases increased.