Effect of protocatechuic acid-layered double hydroxide nanoparticles on diethylnitrosamine/phenobarbital-induced hepatocellular carcinoma in mice

Apigenin enhances sorafenib anti-tumour efficacy in hepatocellular carcinoma

BACKGROUND

The "one drug-one target" paradigm has various limitations affecting drug efficacy, such as resistance profiles and adverse effects. Combinational therapies help reduce unexpected off-target effects and accelerate therapeutic efficacy. Sorafenib- an FDA-approved drug for liver cancer, has multiple limitations. Therefore, it is recommended to identify an agent that increases its effectiveness and reduces toxicity. In this regard, Apigenin, a plant flavone, would be an excellent option to explore.

METHODS

We used in silico, in vitro, and animal models to explore our hypothesis. For the in vitro study, HepG2 and Huh7 cells were exposed to Apigenin (12-96 μM) and Sorafenib (1-10 μM). For the in vivo study, Diethylnitrosamine (DEN) (25 mg/kg) induced tumor-bearing animals were given Apigenin (50 mg/kg) or Sorafenib (10 mg/kg) alone and combined. Apigenin's bioavailability was checked by UPLC. Tumor nodules were studied macroscopically and by Scanning Electron Microscopy (SEM). Biochemical analysis, histopathology, immunohistochemistry, and qRT-PCR were done.

RESULTS

The results revealed Apigenin's good bioavailability. In silico study showed binding affinity of both chemicals with p53, NANOG, ß-Catenin, c-MYC, and TLR4. We consistently observed a better therapeutic efficacy in combination than alone treatment. Combination treatment showed i) better cytotoxicity, apoptosis induction, and cell cycle arrest of tumor cells, ii) tumor growth reduction, iii) increased expression of p53 and decreased Cd10, Nanog, ß-Catenin, c-Myc, Afp, and Tlr4.

CONCLUSIONS

In conclusion, Apigenin could enhance the therapeutic efficacy of Sorafenib against liver cancer and may be a promising therapeutic approach for treating HCC. However, further research is imperative to gain more in-depth mechanistic insights.

Assessment of the therapeutic potential of a novel phosphoramidate acyclic nucleoside on induced hepatocellular carcinoma in rat model

AIMS

Hepatocellular Carcinoma (HCC) is renowned as a deadly primary cancer of hepatic origin. Sorafenib is the drug-of-choice for targeted treatment of unresectable end-stage HCC. Unfortunately, great proportion of HCC patients showed intolerance or unresponsiveness to treatment. This study assesses potency of novel ProTide; SH-PAN-19 against N-Nitrosodiethylamine (DEN)-induced HCC in male Wistar rats, compared to Sorafenib.

MAIN METHODS

Structural entity of the synthesized compound was substantiated via FT-IR, UV-Vis, 1H NMR and 13C NMR spectroscopic analysis. In vitro, SH-PAN-19 cytotoxicity was tested against 3 human cell lines; hepatocellular carcinoma; HepG-2, colorectal carcinoma; HCT-116 and normal fibroblasts; MRC-5. In vivo, therapeutic efficacy of SH-PAN-19 (300 mg/kg b.w./day) against HCC could be revealed and compared to that of Sorafenib (15 mg/kg b.w./day) by evaluating the morphometric, biochemical, histopathological, immunohistochemical and molecular key markers.

KEY FINDINGS

SH-PAN-19 was relatively safe toward MRC-5 cells (IC50 = 307.6 μg/mL), highly cytotoxic to HepG-2 cells (IC50 = 24.9 μg/mL) and prominently hepato-selective (TSI = 12.35). Oral LD50 of SH-PAN-19 was >3000 mg/kg b.w. DEN-injected rats suffered hepatomegaly, oxidative stress, elevated liver enzymes, hypoalbuminemia, bilirubinemia and skyrocketed AFP plasma titre. SH-PAN-19 alleviated the DEN-induced alterations in apoptotic, angiogenic and inflammatory markers. SH-PAN-19 produced a 2.5-folds increase in Caspase-9 and downregulated VEGFR-2, IL-6, TNF-α, TGFβ-1, MMP-9 and CcnD-1 to levels comparable to that elicited by Sorafenib. SH-PAN-19 resulted in near-complete pathological response versus partial response achieved by Sorafenib.

SIGNIFICANCE

This research illustrated that SH-PAN-19 is a promising chemotherapeutic agent capable of restoring cellular plasticity and could stop HCC progression.

Targeting the NF-κB p65/Bcl-2 signaling pathway in hepatic cellular carcinoma using radiation assisted synthesis of zinc nanoparticles coated with naturally isolated gallic acid

PURPOSE

Oral diethylnitrosamine (DEN) is a known hepatocarcinogen that damages the liver and causes cancer. DEN damages the liver through reactive oxygen species-mediated inflammation and biological process regulation.

MATERIALS AND METHODS

Gallic acid-coated zinc oxide nanoparticles (Zn-GANPs) were made from zinc oxide (ZnO) synthesized by irradiation dose of 50 kGy utilizing a Co-60 γ-ray source chamber with a dose rate of 0.83 kGy/h and gallic acid from pomegranate peel. UV-visible (UV) spectrophotometry verified Zn-GANP synthesis. TEM, DLS, and FTIR were utilized to investigate ZnO-NPs' characteristics. Rats were orally exposed to DEN for 8 weeks at 20 mg/kg five times per week, followed by intraperitoneal injection of Zn-GANPs at 20 mg/kg for 5 weeks. Using oxidative stress, anti-inflammatory, liver function, histologic, apoptotic, and cell cycle parameters for evaluating Zn-GANPs treatment.

RESULTS

DEN exposure elevated inflammatory markers (AFP and NF-κB p65), transaminases (AST, ALT), γ-GT, globulin, and total bilirubin, with reduced protein and albumin levels. It also increased MDA levels, oxidative liver cell damage, and Bcl-2, while decreasing caspase-3 and antioxidants like GSH, and CAT. Zn-GANPs significantly mitigated these effects and lowered lipid peroxidation, AST, ALT, and γ-GT levels, significantly increased CAT and GSH levels (p<0.05). Zn-GANPs caused S and G2/M cell cycle arrest and G0/G1 apoptosis. These results were associated with higher caspase-3 levels and lower Bcl-2 and TGF-β1 levels. Zn-GANPs enhance and restore the histology and ultrastructure of the liver in DEN-induced rats.

CONCLUSION

The data imply that Zn-GANPs may prevent and treat DEN-induced liver damage and carcinogenesis.

Escin-sorafenib synergy up-regulates LC3-II and p62 to induce apoptosis in hepatocellular carcinoma cells

INTRODUCTION

Hepatocellular carcinoma (HCC) is a common solid cancer and the leading cause of cancer deaths worldwide. Sorafenib is the first drug used to treat HCC but its effectiveness needs to be improved, and it is important to find ways to treat cancer that combine sorafenib with other drugs. Synergistic therapies lower effective drug doses and side effects while enhancing the anticancer effect.

PURPOSE

In the present study, the therapeutic potential of sorafenib in combination with escin and its underlying mechanism in targeting liver cancer has been established.

STUDY DESIGN/METHODS

The IC50 of sorafenib and escin against HepG2, PLC/PRF5 and Huh7 cell lines were determined using MTT assay. The combination index, dose reduction index, isobologram and concentrations producing synergy were evaluated using the Chou-Talaly algorithm. The sub-effective concentration of sorafenib and escin was selected to analyze cytotoxic synergistic potential. Cellular ROS, mitochondrial membrane potential, annexin V and cell cycle were evaluated using a flow-cytometer, and autophagy biomarkers were determined using western blotting. Moreover, autophagy was knocked down using ATG5 siRNA to confirm its role. A DEN-induced liver cancer rat model was developed to check the synergy of sorafenib and escin.

RESULTS

Different concentrations of escin reduced the IC50 of sorafenib in HepG2, PLC/PRF5 and Huh7 cell lines. Chou-Talaly algorithm determined cytotoxic synergistic concentrations of sorafenib and escin in these cell lines. Mechanistically, this combination over-expressed p62 and LC-II, reflecting autophagy block and induced late apoptosis, further reconfirmed by ATG5 knockdown. Sorafenib and escin combination  reduced HCC serum biomarker α-feto protein (α-FP) by 1.5 folds. This combination restricted liver weight, tumor number and size, also, conserved morphological features of liver cells. The combination selectively targeted the G0 /G1 phase of cancer cells.

CONCLUSION

Escin and sorafenib combination potentially up-regulates p62 to block autophagy to induce late apoptosis in liver cancer cells.

Review of Cocos nucifera L. testa-derived phytonutrients with special reference to phenolics and its potential for encapsulation

Coconut (Cocos nucifera L.) and its value-added products are rich in medium chain triglycerides, polyphenols and flavonoids with a significant anti-oxidant potential. However, coconut and its products are underutilized for the development of nutraceuticals. Coconut testa is a brown cover of the endosperm, which is characterized with the considerable amount of phytonutrients, especially phenolics and flavonoids. The nutrient rich coconut testa is generally diverted for the production of animal feed or abandoned. Around 10-15% of the coconut kernel is removed as testa while preparing coconut desiccated powder. The coconut testa from the virgin coconut oil (VCO) industry also remains underutilized. Nevertheless, biochemical characterization of coconut testa has revealed its enormous anti-oxidant and nutraceutical potential. On the other hand there are reports describing the suitable encapsulation techniques to develop nutraceuticals from the plant-derived bioactives. In this context this review explores the prospect of utilizing the coconut testa-derived phytonutrients in developing a nutraceutical product.

Trained immunity in monocyte/macrophage: Novel mechanism of phytochemicals in the treatment of atherosclerotic cardiovascular disease

Atherosclerosis (AS) is the pathology of atherosclerotic cardiovascular diseases (ASCVD), characterized by persistent chronic inflammation in the vessel wall, in which monocytes/macrophages play a key role. It has been reported that innate immune system cells can assume a persistent proinflammatory state after short stimulation with endogenous atherogenic stimuli. The pathogenesis of AS can be influenced by this persistent hyperactivation of the innate immune system, which is termed trained immunity. Trained immunity has also been implicated as a key pathological mechanism, leading to persistent chronic inflammation in AS. Trained immunity is mediated via epigenetic and metabolic reprogramming and occurs in mature innate immune cells and their bone marrow progenitors. Natural products are promising candidates for novel pharmacological agents that can be used to prevent or treat cardiovascular diseases (CVD). A variety of natural products and agents exhibiting antiatherosclerotic abilities have been reported to potentially interfere with the pharmacological targets of trained immunity. This review describes in as much detail as possible the mechanisms involved in trained immunity and how phytochemicals of this process inhibit AS by affecting trained monocytes/macrophages.

Chemoprotective Effect of Decalactone on Hepatic Cancer via Diminishing the Inflammatory Response and Oxidative Stress

Hepatocellular Carcinoma (HCC) is the 5^th most common type of cancer in all types of cancers, globally. It is well known that the frequency of inflammatory reaction and oxidative stress increases during the HCC. The goal of this study was to see if decalactone could prevent rats against HCC caused by diethylnitrosamine (DEN). Single intraperitoneal administration of DEN (200 mg/kg) used as inducer and weekly intraperitoneal injection of phenobarbital (8 mg/kg) was used as promotor for induction the HCC in rats. Serum alpha fetoprotein (AFP) was used for the confirmation of HCC. Different doses of decalactone (5, 10 and 15 mg/kg) were orally administered to the rats. The body weight was determined at regular time. The hepatic, non-hepatic, antioxidant markers and inflammatory mediators were scrutinized. All groups of animals were scarified and macroscopically examination of the liver tissue was performed and the weight of organ (hepatic tissue) were estimated. Decalactone increased body weight while also suppressing hepatic nodules and tissue weight. Decalactone treatment reduced AFP, total bilirubin, and direct bilirubin levels while increasing albumin and total protein levels in a dose-dependent manner. Decalactone reduced lipid peroxidation (LPO) and increased catalase (CAT), glutathione (GSH), glutathione peroxidase (GPx), and superoxide dismutase (SOD) levels significantly (p < 0.001) (SOD). Decalactone lowered the levels of significantly (p < 0.001) inflammatory cytokines and inflammatory markers in the liver. Based on the findings, we may conclude that decalactone inhibited HCC in DEN-induced HCC animals via reducing oxidative stress and inflammatory mediators.

Protocatechuic acid as a potent anticarcinogenic compound in purple rice bran against diethylnitrosamine-initiated rat hepatocarcinogenesis

Our previous study demonstrated that purple rice bran extract (PRBE) could inhibit diethylnitrosamine (DEN)-induced hepatocarcinogenesis. Protocatechuic acid (PCA) is the major phenolic acid contained in the PRBE. Therefore, this study aimed to determine whether PCA is an anticarcinogenic compound in purple rice extract. Rats were intraperitoneally injected with DEN to induce glutathione S-transferase placental form (GST-P)-positive foci. Rats were fed with PRBE at 500 mg kg⁻¹ body weight or PCA at 4 mg kg⁻¹ body weight for 5 and 15 weeks. PCA administration attenuated DEN-induced hepatic GST-P positive foci to a degree similar to PRBE. The molecular mechanisms of PCA in the initiation stage were correlated with reduced activity of cytochrome P450 reductase and induction of glutathione S-transferase. In addition, PCA also downregulated the expression of TNF-α and IL-1β genes in rat liver. These genes are associated with the inhibition of inflammation. In the promotion stage, PCA suppressed cell proliferation correlated with the downregulation of Cyclin D1 expression. Moreover, it also induced apoptosis, indicated by increased expression of P53 and Bad genes, and decreased the expression of the anti-apoptotic Bcl-xl in DEN-initiated rats. These findings suggest that PCA is an active compound in the anticarcinogenic action of purple rice bran.

Nimbolide attenuates gut dysbiosis and prevents bacterial translocation by improving intestinal barrier integrity and ameliorating inflammation in hepatocellular carcinoma

Gut microbiota imbalance plays a key pathological role in hepatocellular carcinoma (HCC) progression; however, the mechanism is poorly understood. We previously showed nimbolide impede tumor development by improving hepatic tight junction (TJ) proteins expression and attenuating inflammation in HCC mice. Here, we aimed to study the role of nimbolide in regulating gut microbiota imbalance and bacterial translocation (BT) through modulating intestinal TJ proteins in an experimental hepatocarcinogenesis. Nimbolide (6 mg/kg) was administered orally for 4 weeks following induction of HCC in mice at the 28th week. Nimbolide treatment attenuated the gut microbiota imbalance by decreasing 16 s rRNA levels of Escherichia coli, Enterococcus, Bacteroides and increasing Bifidobacterium, and Lactobacillus in the intestinal tissue, which was otherwise altered in HCC mice. Furthermore, nimbolide improved intestinal barrier integrity in HCC mice by upregulating TJ proteins such as occludin and ZO-1 expression and subsequently prevented hepatic BT and decreased BT markers such as LBP, sCD14, and procalcitonin in the plasma of HCC mice. Moreover, nimbolide ameliorated intestinal and hepatic inflammation by downregulating TLR4, MyD88, and NF-κB protein expression in HCC mice. Thus, nimbolide represents a novel therapeutic drug for HCC treatment by targeting the gut-liver axis, which plays an imperative role in HCC pathogenesis.

Anticancer effect of Selenium/Chitosan/Polyethylene glycol/Allyl isothiocyanate nanocomposites against diethylnitrosamine-induced liver cancer in rats

Background

Nano-based drug delivery systems have shown several advantages in cancer treatment like specific targeting of cancer cells, good pharmacokinetics, and lesser adverse effects. Liver cancer is a fifth most common cancer and third leading cause of cancer-related mortalities worldwide.

Objective

The present study focusses to formulate the selenium (S)/chitosan (C)/polyethylene glycol (Pg)/allyl isothiocyanate (AI) nanocomposites (SCPg-AI-NCs) and assess its therapeutic properties against the diethylnitrosamine (DEN)-induced liver cancer in rats via inhibition of oxidative stress and tumor markers.

Methodology

The SCPg-AI-NCs were synthesized by ionic gelation technique and characterized by various characterization techniques. The liver cancer was induced to the rats by injecting a DEN (200 mg/kg) on the 8th day of experiment. Then DEN-induced rats treated with 10 mg/kg of formulated SCPg-AI-NCs an hour before DEN administration for 16 weeks. The 8-hydroxy-2′ -deoxyguanosine (8-OHdG) content, albumin, globulin, and total protein were examined by standard methods. The level of glutathione (GSH), vitamin-C & -E, and superoxide dismutase (SOD), catalase (CAT), glutathione peroxidase (GPx), and glutathione reductase (GR) activities were examined using assay kits. The liver marker enzymes i.e., alanine transaminase (ALT), aspartate tansaminase (AST), γ-glutamyl transaminase (GGT), lactate dehydrogenase (LDH), and alkaline phosphatase (ALP) activities, alpha fetoprotein (AFP) and carcinoembryonic antigen (CEA), Bax, and Bcl-2 levels, and caspase-3&9 activities was examined using assay kits and the liver histopathology was assessed microscopically by hematoxylin and eosin staining method. The effect of formulated SCPg-AI-NCs on the viability and apoptotic cell death on the HepG2 cells were examined using MTT and dual staining assays, respectively.

Results

The results of different characterization studies demonstrated the formation of SCPg-AI-NCs with tetragonal shape, narrowed distribution, and size ranging from 390 to 450 nm. The formulated SCPg-AI-NCs treated liver cancer rats indicated the reduced levels of 8-OHdG, albumin, globulin, and total protein. The SCPg-AI-NCs treatment appreciably improved the GSH, vitamin-C & -E contents, and SOD, CAT, GPx, and GR activities in the serum of liver cancer rats. The SCPg-AI-NCs treatment remarkably reduced the liver marker enzyme activities in the DEN-induced rats. The SCPg-AI-NCs treatment decreased the AFP and CEA contents and enhanced the Bax and caspase 3&9 activities in the DEN-induced rats. The SCPg-AI-NCs effectively decreased the cell viability and induced apoptosis in the HepG2 cells.

Conclusion

The present findings suggested that the formulated SCPg-AI-NCs remarkably inhibited the DEN-induced liver carcinogenesis in rats. These findings provide an evidence that SCPg-AI-NCs can be a promising anticancer nano-drug in the future to treat the liver carcinogenesis.

1,8 Cineole and Ellagic acid inhibit hepatocarcinogenesis via upregulation of MiR-122 and suppression of TGF-β1, FSCN1, Vimentin, VEGF, and MMP-9

Hepatocellular carcinoma (HCC) is one of the most burdened tumors worldwide, with a complex and multifactorial pathogenesis. Current treatment approaches involve different molecular targets. Phytochemicals have shown considerable promise in the prevention and treatment of HCC. We investigated the efficacy of two natural components, 1,8 cineole (Cin) and ellagic acid (EA), against diethylnitrosamine/2-acetylaminofluorene (DEN/2-AAF) induced HCC in rats. DEN/2-AAF showed deterioration of hepatic cells with an impaired functional capacity of the liver. In addition, the levels of tumor markers including alpha-fetoprotein, arginase-1, alpha-L-fucosidase, and ferritin were significantly increased, whereas the hepatic miR-122 level was significantly decreased in induced-HCC rats. Interestingly, treatment with Cin (100mg/kg) and EA (60mg/kg) powerfully restored these biochemical alterations. Moreover, Cin and EA treatment exhibited significant downregulation in transforming growth factor beta-1 (TGF-β1), Fascin-1 (FSCN1), vascular endothelial growth factor (VEGF), matrix metalloproteinase-9 (MMP-9), and epithelial-mesenchymal transition (EMT) key marker, vimentin, along with a restoration of histopathological findings compared to HCC group. Such effects were comparable to Doxorubicin (DOX) (2mg/kg); however, a little additive effect was evident through combining these phytochemicals with DOX. Altogether, this study highlighted 1,8 cineole and ellagic acid for the first time as promising phytochemicals for the treatment of hepatocarcinogenesis via regulating multiple targets.

Anticancer Effects of Tacrolimus on Induced Hepatocellular Carcinoma in Mice

BACKGROUND

Tacrolimus is a calcineurin inhibitor widely used for immunological disorders. However, there is a significant controversy regarding its effect on the liver. The present study was conducted to evaluate the anticancer effects of tacrolimus on an induced murine hepatocellular carcinoma (HCC) model and its possible hepatotoxicity at standard therapeutic doses.

METHODS

Fifty-four male mice were divided into five groups: a control healthy group, control HCC group, tacrolimus-treated group, doxorubicin (DOXO)-treated group, and combined tacrolimus- and DOXO-treated group. The activity of liver enzymes, including alkaline phosphatase, gamma-glutamyl transferase, lactate dehydrogenase, alanine transaminase, and aspartate transaminase, was determined. Serum vascular endothelial growth factor (VEGF) was measured using an enzyme-linked immunosorbent assay. A quantitative real-time polymerase chain reaction (qRT-PCR) was conducted to measure the expression of proliferating cell nuclear antigen (PCNA), Bax, and p53 mRNA. Immunohistochemical staining for cyclin D1 and VEGF was performed.

RESULTS

Mice that received combined treatment with tacrolimus and DOXO exhibited the best improvement in all parameters when compared with the groups that received DOXO or tacrolimus alone (p < 0.001).

CONCLUSION

The combination of DOXO and tacrolimus was more effective in the management of HCC compared with either agent alone. This improvement was detected by the reduction of liver enzymes and the improvement of the histopathological picture. The involved mechanisms included significant apoptosis induction demonstrated by upregulation of bax along with a reduction in angiogenesis demonstrated by downregulation of VEGF. This was accompanied by inhibition of cell cycle progression mediated by upregulated p53 and downregulated PCNA and cyclin D1.

Phyllanthin prevents diethylnitrosamine (DEN) induced liver carcinogenesis in rats and induces apoptotic cell death in HepG2 cells

Liver cancer is a critical clinical condition with augmented malignancy, rapid progression, and poor prognosis. Liver cancer often initiates as fibrosis, develops as cirrhosis, and results in cancer. For centuries, medicinal plants have been incorporated in various liver-associated complications, and recently, research has recognized that many bioactive compounds from medicinal plants may interact with targets related to liver disorders. Phyllanthin from the Phyllanthus species is one such compound extensively used by folklore practitioners for various health benefits. However, most practices continue to be unrecognized scientifically. Hence, in this work, we investigated the protective role of phyllanthin on diethylnitrosamine (DEN) induced liver carcinoma in Wistar Albino rats and the anti-tumor potential on human hepatocellular carcinoma (HCC) HepG2 cells. The DEN-challenged liver cancer in experimental rats caused increased liver weight, 8-OHD, hepatic tissue injury marker, lipid peroxidation, and tumor markers levels. Remarkably, phyllanthin counteracted the DEN effect by ameliorating all the liver function enzymes, oxidative DNA damage, and tumor-specific markers by enhanced anti-oxidant capacity and induced caspase-dependent apoptosis through the mTOR/ PI3K signaling pathway. MTT assay demonstrated that phyllanthin inhibited the HepG2 cell growth in a dose-dependent manner. Fascinatingly, phyllanthin did not demonstrate any substantial effect on the normal cell line, HL7702. In addition, HepG2 cells were found in the late apoptotic stage upon treatment with phyllanthin as depicted by acridine orange/ethidium bromide staining. Overall, this work offers scientific justification that phyllanthin can be claimed to be a safe candidate with potential chemotherapeutic activity against HCC.

New nanocarried phenobarbital formulation: Maintains better control of pentylenetetrazole-Induced seizures

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For the first time, phenobarbital was intercalated in the layered double hydroxide.

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This study evaluated the slow release efficacy of intercalated phenobarbital.

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The time of the anticonvulsant effect was verified by electroencephalographic records.

This study aims to evaluate the efficacy of slow release phenobarbital in the control of convulsions triggered by pentylenetetrazole (PTZ), verifying the time of permanence in the anticonvulsant effect through behavior and electroencephalographic records. A total of 162 male Wistar rats weighing between 100 and 120 g were divided into two groups, one for behavior analysis (n = 90) and biochemistry, and another for the acquisition of electrocorticographic record (n = 72). Hepatic enzymes were measured by obtaining a blood sample from the animals studied by means of a biochemical analysis. The procedures for electrode implant and electrocorticographic recordings were performed. The intercalation of phenobarbital in layered double hydroxide (LDH) nanocarrier allowed us to evaluate a new slow release pharmaceutical formulation based on methodologies that have proven longer residence time and lower side effects. This study demonstrates that phenobarbital can be a new perspective pharmaceutical formulation.

New progress in the pharmacology of protocatechuic acid: A compound ingested in daily foods and herbs frequently and heavily

Protocatechuic acid is a natural phenolic acid, which widely exists in our daily diet and herbs. It is also one of the main metabolites of complex polyphenols, such as anthocyanins and proanthocyanins. In recent years, a large number of studies on the pharmacological activities of protocatechuic acid have emerged. Protocatechuic acid has a wide range of pharmacological activities including antioxidant, anti-inflammatory, neuroprotective, antibacterial, antiviral, anticancer, antiosteoporotic, analgesia, antiaging activties; protection from metabolic syndrome; and preservation of liver, kidneys, and reproductive functions. Pharmacokinetic studies showed that the absorption and elimination rate of protocatechuic acid are faster, with glucuronidation and sulfation being the major metabolic pathways. However, protocatechuic acid displays a dual-directional regulatory effect on some pharmacological activities. When the concentration is very high, it can inhibit cell proliferation and reduce survival rate. This review aims to comprehensively summarize the pharmacology, pharmacokinetics, and toxicity of protocatechuic acid with emphasis on its pharmacological activities discovered in recent 5 years, so as to provide more up-to-date and thorough information for the preclinical and clinical research of protocatechuic acid in the future. Moreover, it is hoped that the clinical application of protocatechuic acid can be broadened, giving full play to its characteristics of rich sources, low toxicity and wide pharmacological activites.

Therapeutic Potential of Plant Phenolic Acids in the Treatment of Cancer

Globally, cancer is the second leading cause of death. Different conventional approaches to treat cancer include chemotherapy or radiotherapy. However, these are usually associated with various deleterious effects and numerous disadvantages in clinical practice. In addition, there are increasing concerns about drug resistance. In the continuous search for safer and more effective treatments, plant-derived natural compounds are of major interest. Plant phenolics are secondary metabolites that have gained importance as potential anti-cancer compounds. Phenolics display a great prospective as cytotoxic anti-cancer agents promoting apoptosis, reducing proliferation, and targeting various aspects of cancer (angiogenesis, growth and differentiation, and metastasis). Phenolic acids are a subclass of plant phenolics, furtherly divided into benzoic and cinnamic acids, that are associated with potent anticancer abilities in various in vitro and in vivo studies. Moreover, the therapeutic activities of phenolic acids are reinforced by their role as epigenetic regulators as well as supporters of adverse events or resistance associated with conventional anticancer therapy. Encapsulation of phyto-substances into nanocarrier systems is a challenging aspect concerning the efficiency of natural substances used in cancer treatment. A summary of phenolic acids and their effectiveness as well as phenolic-associated advances in cancer treatment will be discussed in this review.