Punicalagin attenuates TNF-α-induced oxidative damage and promotes osteogenic differentiation of bone mesenchymal stem cells by activating the Nrf2/HO-1 pathway.

Oxidative stress is one of the most important factors in changing bone homeostasis. Redox homeostasis plays a key role in the osteogenic differentiation of bone mesenchymal stem cells (BMSCs) and the angiogenesis ability of human umbilical vein endothelial cells (HUVECs) for bone regeneration. Currently, this study assessed the effects of punicalagin (PUN) on BMSCs and HUVECs. Cell viability was determined by CCK-8 assay. A flow cytometry analysis was adopted to detect macrophage polarization. The production of reactive oxygen stress (ROS), glutathione (GSH), malonaldehyde (MDA) and superoxide dismutase (SOD) activities were evaluated by using commercially-available kits. Osteogenic capacity of BMSCs was evaluated by ALP activity, ALP staining and ARS staining. The expression of osteogenic-related proteins (OCN, Runx-2, OPN) and Nrf/HO-1 levles were evaluated by Western blotting. Osteogenic-related genes (Osterix, COL-1, BMP-4, ALP) were evaluated by RT-PCR. Migration ability and invasion ability of HUVECs were evaluated by wound healing assay and Transwell assay. Angiogenic ability was detected by tube formation assay and the expression of angiogenic-related genes (VEGF, vWF, CD31) were evaluated by RT-PCR. Results showed that PUN alleviated oxidative stress by TNF-α, enhanced osteogenic differentiation in BMSCs and angiogenesis in HUVECs. Moreover, PUN regulate immune microenvironment by promoting the polarization of M2 macrophages and reduce the oxidative stress related products by activating Nrf2/HO-1 pathway. Altogether, these results suggested that PUN can promote osteogenic capacity of BMSCs, angiogenesis of HUVECs, alleviate oxidative stress via Nrf2/HO-1 pathway, offering PUN as a novel antioxidant agent for treating bone loss diseases.

Oral administration of punicalagin attenuates imiquimod-induced psoriasis by reducing ROS generation and inflammation via MAPK/ERK and NF-κB signaling pathways.

Psoriasis, an immune-mediated chronic inflammatory skin disease, imposes a huge mental and physical burden on patients and severely affects their quality of life. Punicalagin (PU), the most abundant ellagitannin in pomegranates, has become a research hotspot owing to its diverse biological activities. However, its effects on psoriasis remain unclear. We explored the impact and molecular mechanism of PU on M5-stimulated keratinocyte cell lines and imiquimod (IMQ)-induced psoriasis-like skin inflammation in BABL/c mice using western blotting, quantitative real-time polymerase chain reaction (qRT-PCR), hematoxylin and eosin (H&E) stain, immunohistochemistry, and immunofluorescent. Administration of PU-enriched pomegranate extract at dosages of 150 and 250 mg/kg/day markedly attenuated psoriatic severity, abrogated splenomegaly, and reduced IMQ-induced abnormal epidermal proliferation, CD4+ T-cell infiltration, and inflammatory factor expression. Moreover, PU could decrease expression levels of pro-inflammatory cytokines, such as IL-1ß, IL-1α, IL-6, IL-8, TNF-α, IL-17A, IL-22, IL-23A, and reactive oxygen species (ROS), followed by keratinocyte proliferation inhibition in the M5-stimulated cell line model of inflammation through inhibition of mitogen-activated protein kinases/extracellular regulated protein kinases (MAPK/ERK) and nuclear factor kappaB (NF-κB) signaling pathways. Our results indicate that PU may serve as a promising nutritional intervention for psoriasis by ameliorating cellular oxidative stress and inflammation.

Anti-Culex pipiens activity of different pomegranate cultivars and determination of their bioactive compounds using LC-MS profiling.

INTRODUCTION: Pomegranate (Punica granatum L.) peels are rich in various bioactive compounds. Characterization of these compounds is crucial for the utilization of peel waste in industrial processing. OBJECTIVE: The study aimed (1) to establish and compare the metabolic profiles of the peel of seven pomegranate cultivars and (2) to identify bioactive compounds contributing to the larvicidal activity against the third instar larvae of Culex pipiens. MATERIALS AND METHODS: UPLC-ESI-MS/MS was utilized to analyze peel methanol extracts of different pomegranate cultivars. The larvicidal activity was determined by calculating the larval mortality among the third instar larvae of C. pipiens. Multivariate data analysis was conducted to identify the metabolites that exhibited a larvicidal effect. RESULTS: A total of 24 metabolites, including hydrolyzable tannins, flavonoids, and alkaloids, were tentatively identified in both negative and positive ionization modes. The extract of cultivar 'Black' exhibited the most potent larvicidal effect with LC50 values of 185.15, 156.84, and 138.12 ppm/mL after 24, 48, and 72 h of treatment, respectively. By applying chemometric techniques, the larvicidal activity could be directly correlated to the bioactive compounds punicalagin, quercetin-O-rhamnoside, quercetin-O-pentoside, and galloyl-HHDP-glucose. CONCLUSION: The present study implemented UPLC-ESI-MS/MS and chemometric techniques as potential tools for metabolomics analysis and differentiation between peels of different pomegranate cultivars. In addition, cultivar 'Black' extract could be a promising natural insecticide against mosquitoes since it is rich in bioactive compounds with larvicidal activity.

Multifaceted Neuroprotective Role of Punicalagin: A Review.

Millions of people worldwide are currently afflicted with neurologic conditions like a seizure, depression, stress, Alzheimer's disease, Parkinson's disease, and Huntington's disease. However, the precise etiopathology of these diseases is still unknown. Substantial studies are being conducted to discover more treatments against these disorders because many patients do not experience the therapeutic benefits that would be expected from using existing pharmaceutical strategies. Herbal medicines which have been used in traditional medicine for millennia to treat various neurological problems are also being investigated and scientifically assessed. Punicalagin is a known polyphenol that has significant antioxidant, anti-inflammatory, anti-viral, anti-proliferative, and anti-cancer properties. Around the world, traditional use of herbal drugs is gaining wider acceptance as a part of complementary and alternative medicine. The scientific community should pay attention to these many neuroprotective pharmacodynamic activities of Punicalagin to create effective pharmacotherapeutic plans, as evidenced by mounting data in pre-clinical research investigations. The current review describes the recent studies on the pharmacological effects of Punicalagin in a variety of neurological illnesses and paves the way for further study in this field.

Neuroprotective Potential of Punicalagin, a Natural Component of Pomegranate Polyphenols: A Review.

Neurodegenerative diseases (NDs), such as Alzheimer's disease (AD) and Parkinson's disease (PD), are major health problems worldwide. To date, available remedies against NDs are limited. In fact, current treatment options include drug intervention and nutritional therapy, which mainly focus on the repair of neuronal damage and functional monitoring. However, these treatments do not completely alleviate disease symptoms. Recently, eliminating harmful molecules, such as reactive oxygen species, and inhibiting neuroinflammation have become potential strategies recommended by many researchers. Accordingly, remarkable interest has been generated in recent years regarding natural products, including polyphenols, that provide neuroprotective effects. In this review, we aimed to provide experimental evidence of the therapeutic potential of punicalagin (PUN), a prevailing compound in pomegranate polyphenols with antioxidant activity. Overall, the chemistry, methods of determination, characteristics of metabolism, transformation mechanisms of action, and neuroprotective effects of PUN on NDs are summarised to provide a scientific basis for elucidating the therapeutic mechanisms and targets of NDs.

Pomegranate polyphenol punicalagin improves learning memory deficits, redox homeostasis, and neuroinflammation in aging mice.

Alzheimer's disease (AD) is an irreversible, progressive brain disorder characterized by loss of memory and cognitive dysfunction in the aged. Despite remarkable advances in drug therapy, effective pharmacological interventions are rare. Punicalagin (PU) is an active antioxidant polyphenol found in pomegranates, raspberries, blueberries, and chestnuts that has attracted considerable attention owing to its strong antioxidant and anti-inflammatory properties. The current study focused on the neuroprotective effect of PU on aging mice and its potential mechanisms. In this study, we first evaluated the protective effect of PU on neuro-2a (N2a) cell damage mediated by BV2 microglia-induced neuroinflammation. The in vivo D-galactose (D-gal)-induced brain aging model demonstrated that PU ameliorated deficits in learning and memory and prevented neuroinflammation, which was evident from the decrease in microglial activation and astrocytosis. Furthermore, PU reduced the levels of malondialdehyde (MDA) and reactive oxygen species (ROS) and inhibited NLRP3 inflammasome activation, reducing the levels of inflammatory cytokines, such as interleukin-6 (IL-6), tumor necrosis factor-a (TNF-a), interleukin-18 (IL-18), and interleukin-1 beta (IL-1ß) in both accelerated aging and naturally senescent mouse models. PU effectively improved neuroinflammation, learning and memory deficits, and redox homeostasis in aging mice, and it could be a potential therapeutic agent for AD.

The Role of Punicalagin and Its Metabolites in Atherosclerosis and Risk Factors Associated with the Disease.

Atherosclerotic cardiovascular disease (ACVD) is the leading cause of death worldwide. Although current therapies, such as statins, have led to a marked reduction in morbidity and mortality from ACVD, they are associated with considerable residual risk for the disease together with various adverse side effects. Natural compounds are generally well-tolerated; a major recent goal has been to harness their full potential in the prevention and treatment of ACVD, either alone or together with existing pharmacotherapies. Punicalagin (PC) is the main polyphenol present in pomegranates and pomegranate juice and demonstrates many beneficial actions, including anti-inflammatory, antioxidant, and anti-atherogenic properties. The objective of this review is to inform on our current understanding of the pathogenesis of ACVD and the potential mechanisms underlying the beneficial actions of PC and its metabolites in the disease, including the attenuation of dyslipidemia, oxidative stress, endothelial cell dysfunction, foam cell formation, and inflammation mediated by cytokines and immune cells together with the regulation of proliferation and migration of vascular smooth muscle cells. Some of the anti-inflammatory and antioxidant properties of PC and its metabolites are due to their strong radical-scavenging activities. PC and its metabolites also inhibit the risk factors of atherosclerosis, including hyperlipidemia, diabetes mellitus, inflammation, hypertension, obesity, and non-alcoholic fatty liver disease. Despite the promising findings that have emerged from numerous in vitro, in vivo, and clinical studies, deeper mechanistic insights and large clinical trials are required to harness the full potential of PC and its metabolites in the prevention and treatment of ACVD.

Preventive and Therapeutic Effects of Punica granatum L. Polyphenols in Neurological Conditions.

Pomegranate (Punica granatum L.) is a polyphenol-rich food and medicinal plant containing flavonols, anthocyanins, and tannins. Ellagitannins (ETs) are the most abundant polyphenols in pomegranate. A growing body of research shows that polyphenol-rich pomegranate extracts and their metabolites target multiple types of brain cell and support their redox balance, proliferation and survival, as well as cell signaling. Independent studies have demonstrated that the significant neuroprotective effects of ETs are mediated by their antioxidant and anti-inflammatory effects, their chelating properties, by their ability to activate various signaling pathways, as well as the ability to influence mitochondrial damage, thus regulating autophagy, apoptosis and neurotransmitter signaling. The multitude of in vitro and in vivo studies summarized in the present review suggest that pomegranate polyphenols act on both neuronal and glial cells directly, and also affect blood-brain barrier function, restoring redox balance in the blood and brain and increasing blood flow to the brain.

Protein Disulfide Isomerase A3 (PDIA3): A Pharmacological Target in Glioblastoma?

The protein disulfide isomerase A3 (PDIA3) is directly or indirectly involved in various physiopathological processes and participates in cancer initiation, progression and chemosensitivity. However, little is known about its involvement in glioblastoma. To obtain specific information, we performed cellular experiments in the T98G and U-87 MG glioblastoma cell lines to evaluate the role of PDIA3. The loss of PDIA3 functions, either through inhibition or silencing, reduced glioblastoma cells spreading by triggering cytotoxic phenomena. PDIA3 inhibition led to a redistribution of PDIA3, resulting in the formation of protein aggregates visualized through immunofluorescence staining. Concurrently, cell cycle progression underwent arrest at the G1/S checkpoint. After PDIA3 inhibition, ROS-independent DNA damage and the activation of the repair system occurred, as evidenced by the phosphorylation of H2A.X and the overexpression of the Ku70 protein. We also demonstrated through a clonogenic assay that PDIA3 inhibition could increase the chemosensitivity of T98G and U-87 MG cells to the approved glioblastoma drug temozolomide (TMZ). Overall, PDIA3 inhibition induced cytotoxic effects in the analyzed glioblastoma cell lines. Although further in vivo studies are needed, the results suggested PDIA3 as a novel therapeutic target that could also be included in already approved therapies.

Pomegranate (Punica granatum L.) and Its Rich Ellagitannins as Potential Inhibitors in Ulcerative Colitis.

Ulcerative colitis, an immune-mediated inflammatory disease of the gastrointestinal tract, places a significant financial burden on patients and the healthcare system. Recently, reviews of the pomegranate and the abundant medicinal applications of its ellagitannins, as well as its pharmacological action, phytochemicals, metabolism, and pharmacokinetics, have been completed. However, summaries on their anti-ulcerative colitis effects are lacking. Numerous preclinical animal investigations and clinical human trial reports demonstrated the specific therapeutic effects of pomegranate and the effect of its ellagitannins against ulcerative colitis. According to the literature collected by Sci-finder and PubMed databases over the past 20 years, this is the first review that has compiled references regarding how the rich ellagitannins found in pomegranate have altered the ulcerative colitis. It was suggested that the various parts of pomegranates and their rich ellagitannins (especially their primary components, punicalagin, and ellagic acid) can inhibit oxidant and inflammatory processes, regulate the intestinal barrier and flora, and provide an anti-ulcerative colitis resource through dietary management.

A Citrus and Pomegranate Complex Reduces Methylglyoxal in Healthy Elderly Subjects: Secondary Analysis of a Double-Blind Randomized Cross-Over Clinical Trial.

Reactive α-dicarbonyls (α-DCs), such as methylglyoxal (MGO), glyoxal (GO), and 3-deoxyglucosone (3-DG), are potent precursors in the formation of advanced glycation end products (AGEs). In particular, MGO and MGO-derived AGEs are thought to be involved in the development of vascular complications in diabetes. Experimental studies showed that citrus and pomegranate polyphenols can scavenge α-DCs. Therefore, the aim of this study was to evaluate the effect of a citrus and pomegranate complex (CPC) on the α-DCs plasma levels in a double-blind, placebo-controlled cross-over trial, where thirty-six elderly subjects were enrolled. They received either 500 mg of Citrus sinensis peel extract and 200 mg of Punica granatum concentrate in CPC capsules or placebo capsules for 4 weeks, with a 4-week washout period in between. For the determination of α-DCs concentrations, liquid chromatography tandem mass spectrometry was used. Following four weeks of CPC supplementation, plasma levels of MGO decreased by 9.8% (-18.7 nmol/L; 95% CI: -36.7, -0.7 nmol/L; p = 0.042). Our findings suggest that CPC supplementation may represent a promising strategy for mitigating the conditions associated with MGO involvement. This study was registered on clinicaltrials.gov as NCT03781999.

[Punicalagin inhibits hepatic lipid deposition in obese mice via AMPK/ACC pathway].

Hepatic lipid deposition is one of the basic manifestations of obesity, and nowadays pharmacological treatment is the most important tool. Punicalagin(PU), a polyphenol derived from pomegranate peel, is a potential anti-obesity substance. In this study, 60 C57BL/6J mice were randomly divided into a normal group and a model group. After establishing a model of simple obesity with a high-fat diet for 12 weeks, the successfully established rat models of obesity were then regrouped into a model group, an orlistat group, a PU low-dose group, a PU medium-dose group, and a PU high-dose group. The normal group was kept on routine diet and other groups continued to feed the high-fat diet. The body weight and food intake were measured and recorded weekly. After 8 weeks, the levels of the four lipids in the serum of each group of mice were determined by an automatic biochemical instrument. Oral glucose tole-rance and intraperitoneal insulin sensitivity were tested. Hemoxylin-eosin(HE) staining was applied to observe the hepatic and adipose tissues. The mRNA expression levels of peroxisome proliferators-activated receptor γ(PPARγ) and C/EBPα were determined by real-time quantitative polymerase chain reaction(Q-PCR), and the mRNA and protein expression levels of adenosine 5'-monophosphate-activated protein kinase(AMPK), anterior cingulate cortex(ACC), and carnitine palmitoyltransferase 1A(CPT1A) were determined by Western blot. Finally, the body mass, Lee's index, serum total glyceride(TG), serum total cholesterol(TC), and low-density lipoprotein cholesterol(LDL-C) levels were significantly higher and high-density lipoprotein cholesterol(HDL-C) levels were significantly lower in the model group as compared with the normal group. The fat deposition in the liver was significantly increased. The mRNA expression levels of hepatic PPARγ and C/EBPα and the protein expression level of ACC were increased, while the mRNA and protein expression levels of CPT-1α(CPT1A) and AMPK were decreased. After PU treatment, the above indexes of obese mice were reversed. In conclusion, PU can decrease the body weight of obese mice and control their food intake. It also plays a role in the regulation of lipid metabolism and glycometabolism metabolism, which can significantly improve hepatic fat deposition. Mechanistically, PU may regulate liver lipid deposition in obese mice by down-regulating lipid synthesis and up-regulating lipolysis through activation of the AMPK/ACC pathway.

Punicalagin Targets Atherosclerosis: Gene Expression Profiling of THP-1 Macrophages Treated with Punicalagin and Molecular Docking.

Atherosclerosis is an important cause of cardiovascular disorders worldwide. Natural botanical drugs have attracted attention due to their antioxidant, anti-inflammatory, and antiatherogenic properties in the treatment of atherosclerosis. Punicalagin is the major bioactive component of pomegranate peel, and has been shown to have antioxidant, anti-inflammatory, antiviral, anti proliferation, and anticancer properties. To explore its antiatherogenic properties at a molecular level, we investigated the genome-wide expression changes that occur in differentiated THP1 cells following treatment with a non-toxic dose of punicalagin. We also conducted a molecular docking simulation study to identify the molecular targets of punicalagin.

Punicalagin, an Inhibitor of Sortase A, Is a Promising Therapeutic Drug to Combat Methicillin-Resistant Staphylococcus aureus Infections.

Antimicrobial resistance (AMR) poses a major threat to human health globally. Staphylococcus aureus is recognized as a cause of disease worldwide, especially methicillin-resistant S. aureus (MRSA) and vancomycin-resistant S. aureus (VRSA). The enzyme sortase A (SrtA), present on the cell surface of S. aureus, plays a key role in bacterial virulence without affecting the bacterial viability, and SrtA-deficient S. aureus strains do not affect the growth of bacteria. Here, we found that punicalagin, a natural compound, was able to inhibit SrtA activity with a very low half maximal inhibitory concentration (IC50) value of 4.23 µg/mL, and punicalagin is a reversible inhibitor of SrtA. Moreover, punicalagin has no distinct cytotoxicity toward A549, HEK293T, or HepG2 cells at a much higher concentration than the IC50 detected by MTT [3-(4,5-dimethyl-2-thiazolyl)-2,5-diphenyl-2H-tetrazolium bromide] assays. In addition, punicalagin visibly attenuated the virulence-related phenotype of SrtA in vitro by decreasing adhesion of S. aureus to fibrinogen, reducing the ability of protein A (SpA) displayed on the surface of the bacteria and biofilm formation. Fluorescence quenching elucidated the interaction between punicalagin and SrtA. Molecular docking further implied that the inhibitory activity lay in the bond between punicalagin and SrtA residues LYS190, TYR187, ALA104, and GLU106. In In vivo studies, we surprisingly found that punicalagin had a more effective curative effect combined with cefotaxime when mice were infected with pneumonia caused by MRSA. Essentially, punicalagin, a therapeutic compound targeting SrtA, demonstrates great potential for combating MRSA infections.

Pomegranate juice and punicalagin-mediated chemoprevention of hepatocellular carcinogenesis via regulating miR-21 and NF-κB-p65 in a rat model.

BACKGROUND: Hepatocellular carcinoma (HCC) is the most common neoplasm among primary liver malignancies, accounting for 70%-85% of total liver cancer cases worldwide. It is also the second-leading cause of cancer-related death worldwide. Recent research has investigated naturally occurring products high in polyphenolic compounds in the regression and prevention of HCC. This study investigated the chemoprevention effects of pomegranate juice (PJ) and punicalagin (PCG) against diethylnitrosamine (DENA)-induced hepatocarcinogenesis in male albino rats. METHODS: Animals were randomized into six groups and treated for 11 weeks as follows: group 1 was a negative control group, group 2 was treated orally with 10 mL PJ per kilogram body weight (kg bw), group 3 was treated orally with 18.5 mg PCG/kg bw, and groups 4-6 were injected with an intraperitoneal dose of DENA (50 mg/kg bw) weekly beginning in the third week. Group 4 was a HCC control (DENA-treated group), group 5 was HCC + PJ, and group 6 was HCC + PCG. RESULTS: PJ antagonized DENA-induced elevations of ALAT, TNF-α, NF-κB-p65, GST, MDA, and NO and restored total protein, IL-10, SOD, and CAT levels. Moreover, PJ resulted in downregulation of miR-21, Bcl-2, and Bcl-XL and an upregulation of caspase-3 and Bax mRNA expressions. These chemoprevention effects of PJ also alleviated the hepatic preneoplastic lesions induced by DENA. Although PCG treatment induced some modulation in DENA-treated rats, it did not show potent chemoprevention activity and induced some side effects. CONCLUSION: Both of PJ and PCG downregulated miR-21 expression and triggered apoptosis. However, PJ was more effective than pure PCG in alleviating the hepatic antioxidant defense state and the inflammatory status. So, PJ was superior in prevention of DENA-induced hepatocellular carcinogenesis in rats than pure PCG.

Punicalagin protects against the development of pancreatic injury and insulitis in rats with induced T1DM by reducing inflammation and oxidative stress.

Pancreatic inflammation and oxidative damage remain major concerns in type 1 diabetes mellitus (T1DM). Punicalagin, a major polyphenol in pomegranates, exhibited antioxidant and protective effects on several organs in case of T1DM; however, no study has yet explored the protective effects of punicalagin on the pancreas and islets of Langerhans. T1DM was induced by injecting 40 mg/kg streptozotocin (STZ) intraperitoneally. Punicalagin (1 mg/kg ip) was injected daily for 15 days after T1DM induction. In diabetic rats, punicalagin treatment lowered the levels of inflammatory biomarkers (monocyte chemoattractant protein-1 and C-reactive protein) and adhesion molecules (E-selectin, intercellular adhesion molecule, and vascular cell adhesion molecule) while activating myeloperoxidase activity. Treatment of diabetic rats with punicalagin improved glutathione content and superoxide dismutase, catalase, and glutathione peroxidase activities; upregulated serum paraoxonase-1 activity; and prevented the elevation lipid peroxidation and protein oxidation products in the pancreas. Furthermore, punicalagin protected the pancreas against STZ-induced histopathological alterations and increased immune-reactive ß-cells while reducing leucocyte infiltration into the islets of Langerhans, leading to normalized blood glucose and insulin levels. These findings indicated that punicalagin might protect against the development of insulitis in T1DM. In conclusion, punicalagin exerts a strong protective effect on the pancreas against oxidative injury and inflammation in STZ-induced experimental T1DM. The present results recommend punicalagin as a potential adjuvant for reducing diabetes-associated insulitis.

Use of hyphenated analytical techniques to identify the bioactive constituents of Gunnera perpensa L., a South African medicinal plant, which potently inhibit SARS-CoV-2 spike glycoprotein-host ACE2 binding.

SARS-CoV-2, the causative agent of COVID-19, continues to cause global morbidity and mortality despite the increasing availability of vaccines. Alongside vaccines, antivirals are urgently needed to combat SARS-CoV-2 infection and spread, particularly in resource-limited regions which lack access to existing therapeutics. Small molecules isolated from medicinal plants may be able to block cellular entry by SARS-CoV-2 by antagonising the interaction of the viral spike glycoprotein receptor-binding domain (RBD) with the host angiotensin-converting enzyme II (ACE2) receptor. As the medicinal plant Gunnera perpensa L. is being used by some South African traditional healers for SARS-CoV-2/COVID-19 management, we hypothesised that it may contain chemical constituents that inhibit the RBD-ACE2 interaction. Using a previously described AlphaScreen-based protein interaction assay, we show here that the DCM:MeOH extract of G. perpensa readily disrupts RBD (USA-WA1/2020)-ACE2 interactions with a half-maximal inhibition concentration (IC50) of < 0.001 µg/mL, compared to an IC50 of 0.025 µg/mL for the control neutralising antibody REGN10987. Employing hyphenated analytical techniques like UPLC-IMS-HRMS (method developed and validated as per the International Conference on Harmonization guidelines), we identified two ellagitannins, punicalin (2.12% w/w) and punicalagin (1.51% w/w), as plant constituents in the DCM:MeOH extract of G. perpensa which antagonised RBD-ACE2 binding with respective IC50s of 9 and 29 nM. This good potency makes both compounds promising leads for development of future entry-based SARS-CoV-2 antivirals. The results also highlight the advantages of combining reverse pharmacology (based on medicinal plant use) with hyphenated analytical techniques to expedite identification of urgently needed antivirals.

ERp57/PDIA3: new insight.

The ERp57/PDIA3 protein is a pleiotropic member of the PDIs family and, although predominantly located in the endoplasmic reticulum (ER), has indeed been found in other cellular compartments, such as the nucleus or the cell membrane. ERp57/PDIA3 is an important research target considering it can be found in various subcellular locations. This protein is involved in many different physiological and pathological processes, and our review describes new data on its functions and summarizes some ligands identified as PDIA3-specific inhibitors.

Punicalagin Protects against the Development of Methotrexate-Induced Hepatotoxicity in Mice via Activating Nrf2 Signaling and Decreasing Oxidative Stress, Inflammation, and Cell Death.

Despite its effectiveness in treating inflammatory diseases and various malignancies, methotrexate (MTX) is well known to cause hepatotoxicity, which involves increased oxidative stress and inflammation, limiting its clinical use. Herein, we looked into the effect of punicalagin (PU), a polyphenolic molecule having a variety of health-promoting attributes, on MTX-induced hepatotoxicity in mice. PU (25 and 50 mg/kg/day) was given orally to the mice for 10 days, while a single dose of MTX (20 mg/kg) was injected intraperitoneally (i.p.) at day 7. The MTX-induced liver damage was demonstrated by remarkably higher transaminases (ALT and AST), ALP, and LDH, as well as significant histological alterations in hepatic tissues. MTX-injected mice also demonstrated increases in hepatic oxidative stress markers, including malondialdehyde (MDA) and nitric oxide (NO), with a concordant drop in glutathione (GSH) content and superoxide dismutase (SOD) and catalase (CAT) activities. PU significantly attenuated the MTX-induced serum transaminases, ALP and LDH elevations, and hepatic oxidative stress measures and boosted antioxidant defenses in the liver. Moreover, the liver of MTX-treated mice showed increases in NF-κB p65 expression, pro-inflammatory cytokine (IL-6 and TNF-α) levels, and pro-apoptotic protein (caspase-3 and Bax) expression, whereas Bcl-2 and Nrf2 expressions were reduced, which were all attenuated by PU treatment. Collectively, PU inhibits oxidative damage, inflammation, and apoptosis and upregulates Nrf2 in the liver of MTX-induced mice. Thus, these findings suggest that PU may have great therapeutic potential for the prevention of MTX-induced hepatotoxicity, pending further exploration in upcoming studies.

Macrophage-Targeted Punicalagin Nanoengineering to Alleviate Methotrexate-Induced Neutropenia: A Molecular Docking, DFT, and MD Simulation Analysis.

Punicalagin is the most bioactive pomegranate polyphenol with high antioxidant and free-radical scavenging activity and can potentially cure different ailments related to the cardiovascular system. The current research work was envisioned to predict the targeting efficiency of punicalagin (PG) nanoparticles to the macrophages, more specifically to bone marrow macrophages. For this, we selected mannose-decorated PLGA-punicalagin nanoparticles (Mn-PLGA-PG), and before formulating this nanocarrier in laboratory settings, we predicted the targeting efficiency of this nanocarrier by in silico analysis. The analysis proceeded with macrophage mannose receptors to be acquainted with the binding affinity and punicalagin-based nanocarrier interactions with this receptor. In silico docking studies of macrophage mannose receptors and punicalagin showed binding interactions on its surface. PG interacted with hydrogen bonds to the charged residue ASP668 and GLY666 and polar residue GLN760 of the Mn receptor. Mannose with a docking score of -5.811 Kcal/mol interacted with four hydrogen bonds and the mannose receptor of macrophage, and in PLGA, it showed a -4.334 Kcal/mol docking score. Further, the analysis proceeded with density functional theory analysis (DFT) and HOMO-LUMO analysis, followed by an extensive 100 ns molecular dynamics simulation to analyse the trajectories showing the slightest deviation and fluctuation. While analysing the ligand and protein interaction, a wonderful interaction was found among the atoms of the ligand and protein residues. This computational study confirms that this nanocarrier could be a promising lead molecule to regulate the incidence of drug-induced neutropenia. Furthermore, experimental validation is required before this can be stated with complete confidence or before human use.