Anti-septic effects of pellitorine in HMGB1-induced inflammatory responses in vitro and in vivo

From Molecular Mechanisms to Clinical Therapy: Understanding Sepsis-Induced Multiple Organ Dysfunction

Sepsis-induced multiple organ dysfunction arises from the highly complex pathophysiology encompassing the interplay of inflammation, oxidative stress, endothelial dysfunction, mitochondrial damage, cellular energy failure, and dysbiosis. Over the past decades, numerous studies have been dedicated to elucidating the underlying molecular mechanisms of sepsis in order to develop effective treatments. Current research underscores liver and cardiac dysfunction, along with acute lung and kidney injuries, as predominant causes of mortality in sepsis patients. This understanding of sepsis-induced organ failure unveils potential therapeutic targets for sepsis treatment. Various novel therapeutics, including melatonin, metformin, palmitoylethanolamide (PEA), certain herbal extracts, and gut microbiota modulators, have demonstrated efficacy in different sepsis models. In recent years, the research focus has shifted from anti-inflammatory and antioxidative agents to exploring the modulation of energy metabolism and gut microbiota in sepsis. These approaches have shown a significant impact in preventing multiple organ damage and mortality in various animal sepsis models but require further clinical investigation. The accumulation of this knowledge enriches our understanding of sepsis and is anticipated to facilitate the development of effective therapeutic strategies in the future.

Piper nigrum Extract Inhibits the Growth of Human Colorectal Cancer HT-29 Cells by Inducing p53-Mediated Apoptosis

Colorectal cancer (CRC) is a prevalent malignancy of the digestive tract with the second highest mortality rate globally. Piper nigrum is a widely used traditional medicinal plant, exhibiting antitumor activity against various tumor cells. At present, research on the effect of Piper nigrum on CRC is limited to in vitro cytotoxicity, lacking comprehensive mechanism investigations. This study aimed to explore the inhibitory effect and mechanism of Piper nigrum extract (PNE) on HT-29 cells. Firstly, we identified the chemical components of PNE. Then, MTT assay, colony formation assay, JC-1 staining, and flow cytometry were used to analyze the effect of PNE on HT-29 cells in vitro. A xenograft model, histopathological examination, immunohistochemistry, and western blot were used to evaluate the tumor growth inhibitory activity and mechanism of PNE in vivo. The results indicated that PNE could inhibit cell proliferation and colony formation, reduce mitochondrial membrane potential, induce cell apoptosis in vitro, and inhibit tumor growth in vivo. Furthermore, PNE could regulate p53 and its downstream proteins, and subsequently activate the caspase-3 pathway. In summary, PNE probably induced apoptosis of HT-29 cells through the mitochondrial pathway mediated by p53. All these results suggested that PNE might be a potential natural-origin anti-CRC drug candidate.

Piper nigrum Extract: Dietary Supplement for Reducing Mammary Tumor Incidence and Chemotherapy-Induced Toxicity

A low piperine fractional Piper nigrum extract (PFPE) was prepared by mixing cold-pressed coconut oil and honey in distilled water, namely, PFPE-CH. In this study, PFPE-CH was orally administered as a dietary supplement to decrease the risk of tumor formation and reduce the side effects of chemotherapeutic drugs during breast cancer treatment. The toxicity study demonstrated no mortality or adverse effects after administrating PFPE-CH at 5000 mg/kg during a 14-day observation period. Additionally, PFPE-CH at 86 mg/kg BW/day did not cause any harm to the kidney or liver function of the rats for six months. In a cancer prevention study, treatment with PFPE-CH at 100 mg/kg BW for 101 days induced oxidative stress and increased the immune response by altering the levels of cancer-associated cytokines (IL-4, IL-6, and IFN-g), leading to a reduction in the tumor incidence of up to 71.4% without any adverse effects. In combination with doxorubicin, PFPE-CH did not disrupt the anticancer effects of the drug in rats with mammary tumors. Surprisingly, PFPE-CH reduced chemotherapy-induced toxicity by improving some hematological and biochemical parameters. Therefore, our results suggest that PFPE-CH is safe and effective in reducing breast tumor incidence and toxicity of chemotherapeutic drugs during cancer treatment in mammary tumor rats.

Black Pepper (Piper nigrum) Alleviates Oxidative Stress, Exerts Potential Anti-Glycation and Anti-AChE Activity: A Multitargeting Neuroprotective Agent against Neurodegenerative Diseases

Neurodegenerative diseases (NDs) are a family of disorders that cause progressive structural and functional degeneration of neurons. Among all the organs in the body, the brain is the one that is the most affected by the production and accumulation of ROS. Various studies have shown that an increase in oxidative stress is a common pathophysiology for almost all NDs, which further affects various other pathways. The available drugs lack the wide spectrum necessary to confront these complexities altogether. Hence, a safe therapeutic approach to target multiple pathways is highly desirable. In the present study, the hexane and ethyl acetate extracts of Piper nigrum (black pepper), an important spice, were evaluated for their neuroprotective potential in hydrogen peroxide-induced oxidative stress in human neuroblastoma cells (SH-SY5Y). The extracts were also subjected to GC/MS to identify the important bioactives present. The extracts exhibited neuroprotection by significantly decreasing the oxidative stress and restoring the mitochondrial membrane potential in the cells. Additionally, the extracts displayed potent anti-glycation and significant anti-Aβ fibrilization activities. The extracts were competitive inhibitors of AChE. The multitarget neuroprotective mechanism displayed by Piper nigrum indicates it as a potential candidate in the treatment of NDs.

The attenuation effect of low piperine Piper nigrum extract on doxorubicin-induced toxicity of blood chemical and immunological properties in mammary tumour rats

CONTEXT

Many natural extracts have been shown to minimize the toxicity of doxorubicin (Dox). Low piperine Piper nigrum L. (Piperaceae) extract (PFPE) is a natural extract containing many types of antioxidants that may reduce Dox toxicities.

OBJECTIVE

To evaluate the effect of PFPE in attenuating the side effects of Dox.

MATERIALS AND METHODS

Tumour-bearing Sprague Dawley rats were divided into five groups including normal, vehicle, 100 mg/kg BW of PFPE plus 2 mg/kg BW of Dox (P100 + Dox), 100 mg/kg BW of PFPE plus 2 mg/kg BW of Dox (P200 + Dox) and Dox. Rats were treated with Dox and/or PFPE three times/week for 4 weeks. Tumour burden, blood parameters, weight of internal organs and immunological data were investigated.

RESULTS

The addition of 200 mg/kg PFPE significantly restored the levels of AST from 174.60 ± 45.67 U/L in the Dox group near to normal levels at 109.80 ± 4.99 U/L. The combination of PFPE and Dox also decreased the levels of CXCL7, TIMP-1, sICAM-1 and l-selectin about 1.4-1.6-fold compared to Dox group. Feeding rats with 200 mg/kg BW of PFPE combination with Dox slightly increased Th1 from 161.67 ± 14.28 cells in Dox group to 200.75 ± 5.8 cells meanwhile suppressed Treg from 3088 ± 78 cells in Dox to 2561 ± 71 cells.

DISCUSSION AND CONCLUSIONS

This study showed that PFPE ameliorated Dox toxicity in many aspects indicating the role of antioxidant and other substances in the extract on toxicity attenuation. This suggested the using of PFPE may be valuable for Dox treated patients.

The genus Asarum: A review on phytochemistry, ethnopharmacology, toxicology and pharmacokinetics

ETHNOPHARMACOLOGICAL RELEVANCE

In essentially every quadrant of the globe, many species of genus Asarum are used as a common herbal medicine and appear in many formulas or Kampo. Crude drug from several medicinal plants of genus Asarum (MA) known as Asari Radix et Rhizoma (ARR) has been proven to have the functions of dispelling cold, relieving pain, and reducing phlegm according to Traditional Chinese Medicine (TCM) theory for thousands of years.

AIM OF THE STUDY

This article reviews the ethnopharmacology, phytochemistry, pharmacology, toxicology and metabolic kinetics related research of genus Asarum to evaluate its ethnopharmacology use and future opportunities for research.

MATERIALS AND METHODS

Information on relevant studies of the genus Asarum was gathered via the Internet using Baidu Scholar, Web of Science, Elsevier, ResearchGate, ACS, Pudmed and Chinese National Knowledge Infrastructure (CNKI). Additionally, information was also obtained from some local books, PhD, MS's dissertations and Pharmacopeias.

RESULTS

The genus Asarum has played an important role in herbal treatment. At present, more than 277 compounds have been isolated or identified from genus Asarum. Among them, volatile oil and lignans are the major active constituents and important chemotaxonomic markers. Modern pharmacological studies indicated that genus Asarum and its active compounds possess a wide range of pharmacological effects, especially analgesic, anti-inflammatory, neuroprotective, cardiovascular protection, antitussive, immunosuppressive, anti-tumor, and microbicidal activities.

CONCLUSIONS

Based on this review, therapeutic potential of genus Asarum has been demonstrated with the pharmacological effects on inflammation, CNS, respiratory regulation, cardiovascular diseases, cancer and microbial infection. The available literature showed that the major activities of the genus Asarum can be attributed to the active lignans and essential oils. Further in-depth studies on the aspects of the genus for mechanism of actions, metabolism, pharmacokinetics, toxicology, drug interactions, and clinical trials are still limited, thereby intensive research and assessments should be performed.

A Review of Malaysian Herbal Plants and Their Active Constituents with Potential Therapeutic Applications in Sepsis

Sepsis refers to organ failure due to uncontrolled body immune responses towards infection. The systemic inflammatory response triggered by pathogen-associated molecular patterns (PAMPs), such as lipopolysaccharide (LPS) from Gram-negative bacteria, is accompanied by the release of various proinflammatory mediators that can lead to organ damage. The progression to septic shock is even more life-threatening due to hypotension. Thus, sepsis is a leading cause of death and morbidity globally. However, current therapies are mainly symptomatic treatment and rely on the use of antibiotics. The lack of a specific treatment demands exploration of new drugs. Malaysian herbal plants have a long history of usage for medicinal purposes. A total of 64 Malaysian plants commonly used in the herbal industry have been published in Malaysian Herbal Monograph 2015 and Globinmed website (http://www.globinmed.com/). An extensive bibliographic search in databases such as PubMed, ScienceDirect, and Scopus revealed that seven of these plants have antisepsis properties, as evidenced by the therapeutic effect of their extracts or isolated compounds against sepsis-associated inflammatory responses or conditions in in vitro or/and in vivo studies. These include Andrographis paniculata, Zingiber officinale, Curcuma longa, Piper nigrum, Syzygium aromaticum, Momordica charantia, and Centella asiatica. Among these, Z. officinale is the most widely studied plant and seems to have the highest potential for future therapeutic applications in sepsis. Although both extracts as well as active constituents from these herbal plants have demonstrated potential antisepsis activity, the activity might be primarily contributed by the active constituent(s) from each of these plants, which are andrographolide (A. paniculata), 6-gingerol and zingerone (Z. officinale), curcumin (C. longa), piperine and pellitorine (P. nigrum), biflorin (S. aromaticum), and asiaticoside, asiatic acid, and madecassoside (C. asiatica). These active constituents have shown great antisepsis effects, and further investigations into their clinical therapeutic potential may be worthwhile.

Chemistry and Pharmacology of Alkylamides from Natural Origin

Interest in alkylamide, as a class of compound, has grown tremendously in recent years. This interest is due to the many presumed benefits in food, cosmetics, and medicine. This review focuses on the different alkylamides naturally occurring in many plant species. Several methods have been employed for their identification as well as isolation and several in vitro and in vivo studies have revealed their therapeutic effects in various diseases. In general, alkylamides have been reported to have several biological activities and pharmacological effects which include immunomodulatory, antithrombotic, antimicrobial, antiviral, antioxidant, anti-inflammatory, analgesic, anticancer, antidiabetic, and antiprotozoal activities. Moreover, many studies have reported on their mechanisms of action, structure-activity relationship, pharmacokinetics, and toxicity. We herein present an updated report on the chemistry and pharmacology of alkylamides of natural origin.

GRAPHICAL ABSTRACT

New Contributions to Asarum Powder on Immunology Related Toxicity Effects in Lung

Objective. Asarum is widely used in clinical practice of Chinese medicine in the treatment of respiratory diseases. Many toxic ingredients (safrole, etc.) had been found in Asarum that show multiple visceral toxicities. In this study, we performed systematic investigation of expression profiles of genes to take a new insight into unclear mechanism of Asarum toxicities in lung. Methods. mRNAs were extracted from lungs of rats after intragastric administration with/without Asarum powders, and microarray assays were applied to investigate gene expression profiles. Differentially expressed genes with significance were selected to carry out GO analysis. Subsequently, quantitative PCRs were performed to verify the differential expression of Tmprss6, Prkag3, Nptx2, Antxr11, Klk11, Rag2, Olr77, Cd7, Il20, LOC69, C6, Ccl20, LOC68, and Cd163 in lung. Changes of Ampk, Bcl2, Caspase 3, Il1, Il20, Matriptase2, Nfκb, Nptx2, and Rag2 in the lung on protein level were verified by western blotting and immunohistochemistry. Results. Compared with control group, the estimated organ coefficients were relatively increased in Asarum group. Results of GO analysis showed that a group of immune related genes in lung were expressed abnormally. The result of PCRs showed that Ccl20 was downregulated rather than other upregulated genes in the Asarum group. Western blotting and immunohistochemistry images showed that Asarum can upregulate the expression of Ampk, Caspase 3, Il1, Il20, Matriptase2, Nfκb, and Rag2 and downregulate the expression of Bcl2 in lung. Conclusion. Our data suggest that expressions of immune related genes in lung were selectively altered by Asarum. Therefore, inflammatory response was active, by regulating Caspase 3, Il1, Il20, Matriptase2, Nfκb, Rag2, Tmprss6, Prkag3, Nptx2, Antxr1, Klk11, Olr77, Cd7, LOC69, C6, LOC68, Cd163, Ampk, Bcl2, and Ccl20. Our study indicated that inflammatory factors take effect in lung toxicity caused by Asarum, which provides a new insight into molecular mechanism of Asarum toxicities in lung.

Sensory active piperine analogues from Macropiper excelsum and their effects on intestinal nutrient uptake in Caco-2 cells

The phytochemical profile of Macropiper excelsum (G.Forst.) Miq. subsp. excelsum (Piperaceae), a shrub which is widespread in New Zealand, was investigated by LC-MS-guided isolation and characterization via HR-ESI-TOF-MS and NMR spectroscopy. The isolated compounds were sensorily evaluated to identify their contribution to the overall taste of the crude extract with sweet, bitter, herbal and trigeminal impressions. Besides the known non-volatile Macropiper compounds, the lignans (+)-diayangambin and (+)-excelsin, four further excelsin isomers, (+)-diasesartemin, (+)-sesartemin, (+)-episesartemin A and B were newly characterized. Moreover, piperine and a number of piperine analogues as well as trans-pellitorine and two homologues, kalecide and (2E,4E)-tetradecadienoic acid N-isobutyl amide were identified in M. excelsum, some of them for the first time. Methyl(2E,4E)-7-(1,3-benzodioxol-5-yl)hepta-2,4-dienoate was identified and characterized for the first time in nature. Sensory analysis of the pure amides indicated that they contributed to the known chemesthetic effects of Macropiper leaves and fruits. Since the pungent piperine has been shown to affect glucose and fatty acid metabolism in vivo in previous studies, piperine itself and four of the isolated compounds, piperdardine, chingchengenamide A, dihydropiperlonguminine, and methyl(2E,4E)-7-(1,3-benzodioxol-5-yl)hepta-2,4-dienoate, were investigated regarding their effects on glucose and fatty acid uptake by enterocyte-like Caco-2 cells, in concentrations ranging from 0.1 to 100 μM. Piperdardine showed the most pronounced effect, with glucose uptake increased by 83 ± 18% at 100 μM compared to non-treated control cells. An amide group seems to be advantageous for glucose uptake stimulation, but not necessarily for fatty acid uptake-stimulating effects of piperine-related compounds.

Quantitative In Vitro and In Vivo Evaluation of Intestinal and Blood-Brain Barrier Transport Kinetics of the Plant N-Alkylamide Pellitorine

Objective. To evaluate the gut mucosa and blood-brain barrier (BBB) pharmacokinetic permeability properties of the plant N-alkylamide pellitorine. Methods. Pure pellitorine and an Anacyclus pyrethrum extract were used to investigate the permeation of pellitorine through (1) a Caco-2 cell monolayer, (2) the rat gut after oral administration, and (3) the BBB in mice after intravenous and intracerebroventricular administration. A validated bioanalytical UPLC-MS(2) method was used to quantify pellitorine. Results. Pellitorine was able to cross the Caco-2 cell monolayer from the apical-to-basolateral and from the basolateral-to-apical side with apparent permeability coefficients between 0.6 · 10(-5) and 4.8 · 10(-5) cm/h and between 0.3 · 10(-5) and 5.8 · 10(-5) cm/h, respectively. In rats, a serum elimination rate constant of 0.3 h(-1) was obtained. Intravenous injection of pellitorine in mice resulted in a rapid and high permeation of pellitorine through the BBB with a unidirectional influx rate constant of 153 μL/(g·min). In particular, 97% of pellitorine reached the brain tissue, while only 3% remained in the brain capillaries. An efflux transfer constant of 0.05 min(-1) was obtained. Conclusion. Pellitorine shows a good gut permeation and rapidly permeates the BBB once in the blood, indicating a possible role in the treatment of central nervous system diseases.

Exendin-4 inhibits HMGB1-induced inflammatory responses in HUVECs and in murine polymicrobial sepsis

Exendin-4 (EX4) has been reported to attenuate myocardial ischemia and reperfusion (I/R) injury and inflammatory and oxidative responses. Nuclear DNA-binding protein high-mobility group box 1 (HMGB1) protein acts as a late mediator of severe vascular inflammatory conditions. However, the effect of EX4 on HMGB1-induced inflammatory response has not been studied. First, we accessed this question by monitoring the effects of posttreatment EX4 on lipopolysaccharide (LPS) and cecal ligation and puncture (CLP)-mediated release of HMGB1 and HMGB1-mediated regulation of proinflammatory responses in human umbilical vein endothelial cells (HUVECs) and septic mice. Posttreatment EX4 was found to suppress LPS-mediated release of HMGB1 and inhibited HMGB1-mediated hyperpermeability and leukocyte migration in septic mice. EX4 also induced downregulation of CLP-induced release of HMGB1, production of IL-6, and mortality. Collectively, these results suggest that EX4 may be regarded as a candidate therapeutic agent for treatment of vascular inflammatory diseases via inhibition of the HMGB1 signaling pathway.

Role of high-mobility group box-1 protein in disruption of vascular barriers and regulation of leukocyte-endothelial interactions

High-mobility group box-1 protein (HMGB1) is a highly conserved non-histone DNA-binding protein present in the nuclei and cytoplasm of nearly all cell types. The results from recent research provide evidence that HMGB1 is secreted into the extracellular milieu and acts as a pro-inflammatory cytokine and exhibits angiogenic effects to fire the immunological response against the pathological effects. Recently, a great deal of evidence has indicated the critical importance of HMGB1 in mediating vascular barriers dysfunction by modulating the expression of adhesion molecules, such as intercellular adhesion molecule-1, vascular cell adhesion protein 1 and E-selectin on the surface of endothelial cells. Such process promotes the adhesion and migration of leukocytes across the endothelium, leading to breakdown of vascular barriers (blood-brain barrier and blood-retinal barrier) via modulating the expression, content, phosphorylation, and distribution of tight junction proteins. Therefore, here we give an abridged review to understand the mechanistic link between HMGB1 and vascular barriers dysfunction, including interaction with cell-surface receptors and intracellular signaling pathways.