Homoharringtonine increases intestinal epithelial permeability by modulating specific claudin isoforms in Caco-2 cell monolayers

Homoharringtonine: mechanisms, clinical applications and research progress

Homoharringtonine is a natural alkaloid with significant pharmacological potential that has demonstrated promising efficacy in the treatment of hematological malignancies in recent years. This article systematically reviews the pharmacological mechanisms of Homoharringtonine, focusing on its key roles in inducing apoptosis, inhibiting cell cycle progression, and reducing cell migration and invasion. Additionally, HHT exhibits multiple biological activities, including immunomodulation, antiviral effects, and anti-fibrotic properties, with recent studies also revealing its potential neuroprotective functions. In clinical trials, Homoharringtonine has demonstrated promising efficacy in the treatment of hematological malignancies, particularly in various types such as acute myeloid leukemia and chronic myeloid leukemia. Despite the significant antitumor effects observed in clinical applications, its low bioavailability and potential side effects remain major challenges that limit its widespread use. This article details the latest research advancements aimed at enhancing the bioavailability of Homoharringtonine, including various drug delivery systems such as nanoparticles and liposomes, as well as chemical modification strategies. These approaches not only improve HHT's bioavailability in vivo but also enhance its targeting ability while reducing toxicity to normal cells. Furthermore, the combination of HHT with other drugs presents broader prospects for clinical treatment. By exploring the diverse pharmacological activities of Homoharringtonine in depth, this article aims to provide a foundation for developing novel therapeutic approaches based on natural products, thereby advancing HHT's application research in cancer treatment and other fields.

Characteristic Metabolic Changes in Skeletal Muscle Due to Vibrio vulnificus Infection in a Wound Infection Model

Vibrio vulnificus is a bacterium that inhabits warm seawater or brackish water environments and causes foodborne diseases and wound infections. In severe cases, V. vulnificus invades the skeletal muscle tissue, where bacterial proliferation leads to septicemia and necrotizing fasciitis with high mortality. Despite this characteristic, information on metabolic changes in tissue infected with V. vulnificus is not available. Here, we elucidated the metabolic changes in V. vulnificus-infected mouse skeletal muscle using capillary electrophoresis time-of-flight mass spectrometry (CE-TOFMS). Metabolome analysis revealed changes in muscle catabolites and energy metabolites during V. vulnificus infection. In particular, succinic acid accumulated but fumaric acid decreased in the infected muscle. However, the virulence factor deletion mutant revealed that changes in metabolites and bacterial proliferation were abolished in skeletal muscle infected with a multifunctional-autoprocessing repeats-in-toxin (MARTX) mutant. On the other hand, mice that were immunosuppressed via cyclophosphamide (CPA) treatment exhibited a similar level of bacterial counts and metabolites between the wild type and MARTX mutant. Therefore, our data indicate that V. vulnificus induces metabolic changes in mouse skeletal muscle and proliferates by using the MARTX toxin to evade the host immune system. This study indicates a new correlation between V. vulnificus infections and metabolic changes that lead to severe reactions or damage to host skeletal muscle. IMPORTANCE V. vulnificus causes necrotizing skin and soft tissue infections (NSSTIs) in severe cases, with high mortality and sign of rapid deterioration. Despite the severity of the infection, the dysfunction of the host metabolism in skeletal muscle triggered by V. vulnificus is poorly understood. In this study, by using a mouse wound infection model, we revealed characteristic changes in muscle catabolism and energy metabolism in skeletal muscle associated with bacterial proliferation in the infected tissues. Understanding such metabolic changes in V. vulnificus-infected tissue may provide crucial information to identify the mechanism via which V. vulnificus induces severe infections. Moreover, our metabolite data may be useful for the recognition, identification, or detection of V. vulnificus infections in clinical studies.

Homoharringtonine is a transdermal granular permeation enhancer

Although modulation of claudin-1-based tight junction (TJ) in stratum granulosum is an option for transdermal absorption of drugs, granular permeation enhancers have never been developed. We previously found that homoharringtonine (HHT), a natural alkanoid, weakened intestinal epithelial barrier with changing expression and cellular localization of TJ components such as claudin-1 and claudin-4. In the present study, we investigated whether HHT is an epidermal granular permeation enhancer. Treatment of normal human epidermal keratinocytes (NHEK) cells with HHT decreased claudin-1 and claudin-4 but not zonula occludens-1 and E-cadherin. HHT lowered TJ-integrity in NHEK cells, accompanied by permeation-enhancement of dextran (4 kDa) in a dose-dependent manner. Transdermal treatment of mice with HHT weakened epidermal barrier. HHT treatment enhanced transdermal absorption of dextran with a molecular mass of up to 10 kDa. Together, HHT may be a transdermal absorption enhancer.

Spermine protects intestinal barrier integrity through ras-related C3 botulinum toxin substrate 1/phospholipase C-γ1 signaling pathway in piglets

Weaning stress can cause tight junctions damage and intestinal permeability enhancement, which leads to intestinal imbalance and growth retardation, thereby causing damage to piglet growth and development. Spermine can reduce stress. However, the mechanism of spermine modulating the intestinal integrity in pigs remains largely unknown. This study aims to examine whether spermine protects the intestinal barrier integrity of piglets through ras-related C3 botulinum toxin substrate 1 (Rac1)/phospholipase C-γ1 (PLC-γ1) signaling pathway. In vivo, 80 piglets were categorised into 4 control groups and 4 spermine groups (10 piglets per group). The piglets were fed with normal saline or spermine at 0.4 mmol/kg BW for 7 h and 3, 6 and 9 d. In vitro, we investigated whether spermine protects the intestinal barrier after a tumor necrosis factor α (TNF-α) challenge through Rac1/PLC-γ1 signaling pathway. The in vivo study found that spermine supplementation increased tight junction protein mRNA levels and Rac1/PLC-γ1 signaling pathway gene expression in the jejunum of piglets. The serum D-lactate content was significantly decreased after spermine supplementation (P < 0.05). The in vitro study found that 0.1 μmol/L spermine increased the levels of tight junction protein expression, Rac1/PLC-γ1 signaling pathway and transepithelial electrical resistance, and decreased paracellular permeability (P < 0.05). Further experiments demonstrated that spermine supplementation enhanced the levels of tight junction protein expression, Rac1/PLC-γ1 signaling pathway and transepithelial electrical resistance, and decreased paracellular permeability compared with the NSC-23766 and U73122 treatment with spermine after TNF-α challenge (P < 0.05). Collectively, spermine protects intestinal barrier integrity through Rac1/PLC-γ1 signaling pathway in piglets.

Calcium-sensing receptor protects intestinal integrity and alleviates the inflammatory response via the Rac1/PLCγ1 signaling pathway

This study aimed to test the hypothesis that the calcium-sensing receptor (CaSR) can protect intestinal epithelial barrier integrity and decrease inflammatory response mediated by the Ras-related C3 botulinum toxin substrate 1 (Rac1)/phospholipase Cγ1 (PLC-γ1) signaling pathway. IPEC-J2 monolayers were treated without or with TNF-α in the absence or presence of CaSR antagonist (NPS 2143), CaSR overexpression, and Rac1 silencing, PLCγ1 silencing or spermine. Results showed that spermine increased transepithelial electrical resistance (TER), tight junction protein levels, the protein concentration of Rac1/PLC-γ1 signaling pathway, and decreased paracellular permeability in the presence of TNF-α. NPS2143 inhibited spermine-induced change in above-mentioned parameters. CaSR overexpression increased TER, the levels of tight junction proteins and the protein concentration of CaSR, phosphorylated PLCγ1, Rac1, and IP3, and decreased paracellular permeability and contents of interleukin-8 (IL-8) and TNF-α after TNF-α challenge. Rac1 and PLCγ1 silencing inhibited CaSR-induced increase in barrier function and the protein concentration of phosphorylated PLCγ1, Rac1, and IP3, and decrease in contents of IL-8 and TNF-α after TNF-α challenge. These results suggest that CaSR activation protects intestinal integrity and alleviates the inflammatory response by activating Rac1 and PLCγ1 signaling after TNF-α challenge, and spermine can maintain barrier function via CaSR/Rac1/PLC-γ1 pathway.

Tryptophan Ameliorates Barrier Integrity and Alleviates the Inflammatory Response to Enterotoxigenic Escherichia coli K88 Through the CaSR/Rac1/PLC-γ1 Signaling Pathway in Porcine Intestinal Epithelial Cells

Background

Impaired intestinal barrier integrity plays a crucial role in the development of many diseases such as obesity, inflammatory bowel disease, and type 2 diabetes. Thus, protecting the intestinal barrier from pathological disruption is of great significance. Tryptophan can increase gut barrier integrity, enhance intestinal absorption, and decrease intestinal inflammation. However, the mechanism of tryptophan in decreasing intestinal barrier damage and inflammatory response remains largely unknown. The objective of this study was to test the hypothesis that tryptophan can enhance intestinal epithelial barrier integrity and decrease inflammatory response mediated by the calcium-sensing receptor (CaSR)/Ras-related C3 botulinum toxin substrate 1 (Rac1)/phospholipase Cγ1 (PLC-γ1) signaling pathway.

Methods

IPEC-J2 cells were treated with or without enterotoxigenic Escherichia coli (ETEC) K88 in the absence or presence of tryptophan, CaSR inhibitor (NPS-2143), wild-type CaSR overexpression (pcDNA3.1-CaSR-WT), Rac1-siRNA, and PLC-γ1-siRNA.

Results

The results showed that ETEC K88 decreased the protein concentration of occludin, zonula occludens-1 (ZO-1), claudin-1, CaSR, total Rac1, Rho family member 1 of porcine GTP-binding protein (GTP-rac1), phosphorylated phospholipase Cγ1 (p-PLC-γ1), and inositol triphosphate (IP3); suppressed the transepithelial electrical resistance (TEER); and enhanced the permeability of FITC-dextran compared with the control group. Compared with the control group, 0.7 mM tryptophan increased the protein concentration of CaSR, total Rac1, GTP-rac1, p-PLC-γ1, ZO-1, claudin-1, occludin, and IP3; elevated the TEER; and decreased the permeability of FITC-dextran and contents of interleukin-8 (IL-8) and TNF-α. However, 0.7 mM tryptophan+ETEC K88 reversed the effects induced by 0.7 mM tryptophan alone. Rac1-siRNA+tryptophan+ETEC K88 or PLC-γ1-siRNA+tryptophan+ETEC K88 reduced the TEER, increased the permeability of FITC-dextran, and improved the contents of IL-8 and TNF-α compared with tryptophan+ETEC K88. NPS2143+tryptophan+ETEC K88 decreased the TEER and the protein concentration of CaSR, total Rac1, GTP-rac1, p-PLC-γ1, ZO-1, claudin-1, occludin, and IP3; increased the permeability of FITC-dextran; and improved the contents of IL-8 and TNF-α compared with tryptophan+ETEC K88. pcDNA3.1-CaSR-WT+Rac1-siRNA+ETEC K88 and pcDNA3.1-CaSR-WT+PLC-γ1-siRNA+ETEC K88 decreased the TEER and enhanced the permeability in porcine intestine epithelial cells compared with pcDNA3.1-CaSR-WT+ETEC K88.

Conclusion

Tryptophan can improve intestinal epithelial barrier integrity and decrease inflammatory response through the CaSR/Rac1/PLC-γ1 signaling pathway.

Intra-Herb Interactions: Primary Metabolites in Coptidis Rhizoma Extract Improved the Pharmacokinetics of Oral Berberine Hydrochloride in Mice

Primary plant metabolites can be used for artificial preparation of natural deep eutectic solvents (NADESs), which have strong dissolving capacity, good biocompatibility, and biodegradability. In this study, for the first time, we verified that NADESs were present in Coptidis Rhizoma extract and systematically investigated its effects and mechanisms on the pharmacokinetics of oral berberine hydrochloride (BBR), a co-existing bioactive constituent. First, three LC-MS/MS based methods were established and fully validated to determine the levels of 11 primary metabolites in Coptidis Rhizoma extract. According to the weight ratio of four major primary metabolites in the Coptidis Rhizoma extract, a stable “endogenous” NADES was prepared using the heating method by the addition of 350 μl of water to 1,307.8 mg of the mixture of malic acid (490.5 mg), glucose (280.6 mg), sucrose (517.7 mg), and choline chloride (19.0 mg). The prepared NADES showed significant acute toxicity in mice and cytotoxicity in MDCK-MDR1 cells. However, after being diluted 10 times or 100 times, the NADES had no significant acute toxicity or cytotoxicity, respectively. The dilutions of the NADES significantly increased the water solubility of BBR, reduced its efflux in gut sacs and MDCK-MDR1 cell monolayer, and improved its metabolic stability in intestinal S9. In addition, the NADES dilutions reversibly opened the tight junctions between the enterocytes in the gut sacs. Moreover, the NADES dilutions significantly improved the exposure levels of BBR in the portal vein and livers of mice that were administered oral BBR. Malic acid was identified as a major component in the NADES in terms of solubility, acute toxicity, cytotoxicity, and pharmacokinetic-improving effects on oral BBR. In conclusion, the primary metabolites of Coptidis Rhizoma extract could form “endogenous” NADES, and its dilutions improve the pharmacokinetics of oral BBR. This study demonstrates the synergistic interaction of the constituents of Coptidis Rhizoma extract and the potential use of the NADES dilutions in oral BBR delivery.

Ethnopharmacology, chemodiversity, and bioactivity of Cephalotaxus medicinal plants

Cephalotaxus is the only genus of Cephalotaxaceae family, and its natural resources are declining due to habitat fragmentation, excessive exploitation and destruction. In many areas of China, folk herbal doctors traditionally use Cephalotaxus plants to treat innominate swollen poison, many of which are cancer. Not only among Han people, but also among minority ethnic groups, Cephalotaxus is used to treat various diseases, e.g., cough, internal bleeding and cancer in Miao medicine, bruises, rheumatism and pain in Yao medicine, and ascariasis, hookworm disease, scrofula in She medicine, etc. Medicinal values of some Cephalotaxus species and compounds are acknowledged officially. However, there is a lack of comprehensive review summarizing the ethnomedicinal knowledge of Cephalotaxus, relevant medicinal phytometabolites and their bioactivities. The research progresses in ethnopharmacology, chemodiversity, and bioactivities of Cephalotaxus medicinal plants are reviewed and commented here. Knowledge gaps are pinpointed and future research directions are suggested. Classic medicinal books, folk medicine books, herbal manuals and ethnomedicinal publications were reviewed for the genus Cephalotaxus (Sanjianshan in Chinese). The relevant data about ethnobotany, phytochemistry, and pharmacology were collected as comprehensively as possible from online databases including Scopus, NCBI PubMed, Bing Scholar, and China National Knowledge Infrastructure (CNKI). "Cephalotaxus", and the respective species name were used as keywords in database search. The obtained articles of the past six decades were collated and analyzed. Four Cephalotaxus species are listed in the official medicinal book in China. They are used as ethnomedicines by many ethnic groups such as Miao, Yao, Dong, She and Han. Inspirations are obtained from traditional applications, and Cephalotaxus phytometabolites are developed into anticancer reagents. Cephalotaxine-type alkaloids, homoerythrina-type alkaloids and homoharringtonine (HHT) are abundant in Cephalotaxus, e.g., C. lanceolata, C. fortunei var. alpina, C. griffithii, and C. hainanensis, etc. New methods of alkaloid analysis and purification are continuously developed and applied. Diterpenoids, sesquiterpenoids, flavonoids, lignans, phenolics, and other components are also identified and isolated in various Cephalotaxus species. Alkaloids such as HHT, terpenoids and other compounds have anticancer activities against multiple types of human cancer. Cephalotaxus extracts and compounds showed anti-inflammatory and antioxidant activities, immunomodulatory activity, antimicrobial activity and nematotoxicity, antihyperglycemic effect, and bone effect, etc. Drug metabolism and pharmacokinetic studies of Cephalotaxus are increasing. We should continue to collect and sort out folk medicinal knowledge of Cephalotaxus and associated organisms, so as to obtain new enlightenment to translate traditional tips into great therapeutic drugs. Transcriptomics, genomics, metabolomics and proteomics studies can contribute massive information for bioactivity and phytochemistry of Cephalotaxus medicinal plants. We should continue to strengthen the application of state-of-the-art technologies in more Cephalotaxus species and for more useful compounds and pharmacological activities.

The permeability characteristics and interaction of main components from Si-Ni-San in a MDCK epithelial cell monolayer model

1. Si-Ni-San (SNS) possesses extensive therapeutic effects, however, the extent to which main components are absorbed and the mechanisms involved are controversial. 2. In this study, MDCK cell model was used to determine the permeability characteristics and interaction between the major components of Si-Ni-San, including saikosaponin a, paeoniflorin, naringin and glycyrrhizic acid. 3. The transport of the major components was concentration-dependent in both directions. Moreover, the transport of paeoniflorin, naringin and glycyrrhizic acid was significantly reduced at 4 °C or in the presence of NaN3. Additionally, the efflux of paeoniflorin and naringin were apparently reduced in the presence of P-gp inhibitor verapamil. The transport of glycyrrhizic acid was clearly inhibited by the inhibitors of MRP2, indicating that MRP2 may be involved in the transport of glycyrrhizic acid. However, the results indicated that saikosaponin a was absorbed mainly by passive diffusion. Furthermore, the combined incubation of four major components had a powerful sorbefacient effect than a single drug used alone which may be regulated by tight junctions. 4. Taken together, our study provides useful information for pharmacological applications of Si-Ni-San and offers new insights into this ancient decoction for further researches, especially in drug synergism.

Abdulbaqi I, Seok Ming T, Siok Yee C, A. Wahab H, Asif SM, Darwis Y. Liquid and Solid Self-Emulsifying Drug Delivery Systems (SEDDs) as Carriers for the Oral Delivery of Azithromycin: Optimization, In Vitro Characterization and Stability Assessment

Azithromycin (AZM) is a macrolide antibiotic used for the treatment of various bacterial infections. The drug is known to have low oral bioavailability (37%) which may be attributed to its relatively high molecular weight, low solubility, dissolution rate, and incomplete intestinal absorption. To overcome these drawbacks, liquid (L) and solid (S) self-emulsifying drug delivery systems (SEDDs) of AZM were developed and optimized. Eight different pseudo-ternary diagrams were constructed based on the drug solubility and the emulsification studies in various SEDDs excipients at different surfactant to co-surfactant (Smix) ratios. Droplet size (DS) < 150 nm, dispersity (Đ) ≤ 0.7, and transmittance (T)% > 85 in three diluents of distilled water (DW), 0.1 mM HCl, and simulated intestinal fluids (SIF) were considered as the selection criteria. The final formulations of L-SEDDs (L-F1(H)), and S-SEDDs (S-F1(H)) were able to meet the selection requirements. Both formulations were proven to be cytocompatible and able to open up the cellular epithelial tight junctions (TJ). The drug dissolution studies showed that after 5 min > 90% and 52.22% of the AZM was released from liquid and solid SEDDs formulations in DW, respectively, compared to 11.27% of the pure AZM, suggesting the developed SEDDs may enhance the oral delivery of the drug. The formulations were stable at refrigerator storage conditions.

Synergistic Mechanisms of Constituents in Herbal Extracts during Intestinal Absorption: Focus on Natural Occurring Nanoparticles

The systematic separation strategy has long and widely been applied in the research and development of herbal medicines. However, the pharmacological effects of many bioactive constituents are much weaker than those of the corresponding herbal extracts. Thus, there is a consensus that purer herbal extracts are sometimes less effective. Pharmacological loss of purified constituents is closely associated with their significantly reduced intestinal absorption after oral administration. In this review, pharmacokinetic synergies among constituents in herbal extracts during intestinal absorption were systematically summarized to broaden the general understanding of the pharmaceutical nature of herbal medicines. Briefly, some coexisting constituents including plant-produced primary and secondary metabolites, promote the intestinal absorption of active constituents by improving solubility, inhibiting first-pass elimination mediated by drug-metabolizing enzymes or drug transporters, increasing the membrane permeability of enterocytes, and reversibly opening the paracellular tight junction between enterocytes. Moreover, some coexisting constituents change the forms of bioactive constituents via mechanisms including the formation of natural nanoparticles. This review will focus on explaining this new synergistic mechanism. Thus, herbal extracts can be considered mixtures of bioactive compounds and pharmacokinetic synergists. This review may provide ideas and strategies for further research and development of herbal medicines.

Modulation of Intestinal Epithelial Permeability in Differentiated Caco-2 Cells Exposed to Aflatoxin M1 and Ochratoxin A Individually or Collectively

Aflatoxin M1 (AFM1) and ochratoxin A (OTA) are mycotoxins commonly found in milk; however, their effects on intestinal epithelial cells have not been reported. In the present study, we show that AFM1 (0.12 and 12 μM) and OTA (0.2 and 20 μM) individually or collectively increased the paracellular flux of lucifer yellow and fluorescein isothiocyanate (FITC)-dextrans (4 and 40 kDa) and decreased transepithelial electrical resistance values in differentiated Caco-2 cells after 48 h of exposure, indicating increased epithelial permeability. Immunoblotting and immunofluorescent analysis revealed that AFM1, OTA, and their combination decreased the expression levels of tight junction (TJ) proteins and disrupted their structures, namely, claudin-3, claudin-4, occludin, and zonula occludens-1 (ZO-1), and p44/42 mitogen-activated protein kinase (MAPK) partially involved in the mycotoxins-induced disruption of intestinal barrier. The effects of a combination of AFM1 and OTA on intestinal barrier function were more significant (p < 0.05) than those of AFM1 and OTA alone, yielding additive or synergistic effects. The additive or synergistic effects of AFM1 and OTA on intestinal barrier function might affect human health, especially in children, and toxin risks should be considered.

Cephalotaxus Alkaloids

Cephalotaxus alkaloids represent a family of plant secondary metabolites known for 60 years. Significant activity against leukemia in mice was demonstrated for extracts of Cephalotaxus. Cephalotaxine (CET) (1), the major alkaloid of this series was isolated from Cephalotaxus drupacea species by Paudler in 1963. The subsequent discovery of promising antitumor activity among new Cephalotaxus derivatives reported by Chinese, Japanese, and American teams triggered extensive structure elucidation and biological studies in this family. The structural feature of this cephalotaxane family relies mainly on its tetracyclic alkaloid backbone, which comprises an azaspiranic 1-azaspiro[4.4]nonane unit (rings C and D) and a benzazepine ring system (rings A and B), which is linked by its C3 alcohol function to a chiral oxygenated side chain by a carboxylic function alpha to a tetrasubstituted carbon center. The botanical distribution of these alkaloids is limited to the Cephalotaxus genus (Cephalotaxaceae). The scope of biological activities of the Cephalotaxus alkaloids is mainly centered on the antileukemic activity of homoharringtonine (HHT) (2), which in particular demonstrated marked benefits in the treatment of orphan myeloid leukemia and was approved as soon as 2009 by European Medicine Agency and by US Food and Drug Administration in 2012. Its exact mechanism of action was partly elucidated and it was early recognized that HHT (2) inhibited protein synthesis at the level of the ribosome machinery. Interestingly, after a latency period of two decades, the topic of Cephalotaxus alkaloids reemerged as a prolific source of new natural structures. To date, more than 70 compounds have been identified and characterized. Synthetic studies also regained attention during the past two decades, and numerous methodologies were developed to access the first semisynthetic HHT (2) of high purity suitable for clinical studies, and then high grade enantiomerically pure CET (1), HHT (2), and analogs.

TGF-β1 protects intestinal integrity and influences Smads and MAPK signal pathways in IPEC-J2 after TNF-α challenge

The aim of this study was to investigate the protective effects of TGF-β1 on intestinal epithelial barrier, as well as canonical Smad and MAPK signal pathways involved in these protection processes by a IPEC-J2 model stimulated with TNF-α. IPEC-J2 monolayers were treated without or with TNF-α in the absence or presence of TGF-β1. The results showed that TGF-β1 pretreatment ameliorated TNF-α-induced intestinal epithelial barrier disturbances as indicated by decrease of transepithelial electrical resistance (TER) and increase of paracellular permeability. TGF-β1 also dramatically alleviated TNF-α-induced alteration of TJ proteins ZO-1 and occludin. Moreover, TGF-β1 pretreatment increased TβRII protein expression in IPEC-J2 monolayers challenged with TNF-α. In addition, a significant increase of Smad4 and Smad7 mRNA was also observed in the TGF-β1 pretreatment after TNF-α challenge compared with the control group. Furthermore, TGF-β1 pretreatment enhanced smad2 protein activation. These results indicated that the canonical Smad signaling pathway was activated by TGF-β1 pretreatment. Finally, TGF-β1 pretreatment decreased the ratios of the phosphorylated to total JNK and p38 (p-JNK/JNK and p-p38/p38) and increased the ratio of ERK (p-ERK/ERK). Anti-TGF-β1 Abs reduced these TGF-β1 effects. These results indicated that TGF-β1 protects intestinal integrity and influences Smad and MAPK signal pathways in IPEC-J2 after TNF-α challenge.

PEGylated long-circulating liposomes deliver homoharringtonine to suppress multiple myeloma cancer stem cells

The goal of this investigation was to evaluate the inhibiting effect of high proportion polyethyleneglycol of long-circulating homoharringtonine liposomes on RPMI8226 multiple myeloma cancer stem cells. The CD138^-CD34^- multiple myeloma cancer stem cells isolated from RPMI8226 cell line using magnetic activated cell sorting system were, respectively, incubated with the optimized formulation of polyethyleneglycol of long-circulating homoharringtonine liposomes and the homoharringtonine in vitro, and the multiple myeloma cancer stem cell proliferation, colony formation, and cell cycle were analyzed. The inhibition of the multiple myeloma CD138^-CD34^- cancer stem cell growth was investigated in non-obese-diabetic/severe-combined-immunodeficiency mice that were implanted with multiple myeloma RPMI 8226 cancer stem cells and treated with the LCL-HHT-H-PEG. The results showed that the polyethyleneglycol of long-circulating homoharringtonine liposomes significantly inhibited MM cancer stem cell proliferation, colony formation, and induced cancer stem cell apoptosis in vitro as well as MM cancer stem cell growth in non-obese-diabetic/severe-combined-immunodeficiency mice compared with the homoharringtonine. In addition, the mouse bone mineral density and the red blood cell count were significantly increased in polyethyleneglycol of long-circulating homoharringtonine liposomes group. In conclusion, the data demonstrated that the developed polyethyleneglycol of long-circulating homoharringtonine liposomes formulation may serve as an efficient therapeutic drug for suppressing CD138^-CD34^- multiple myeloma cancer stem cell growth by inducing cancer stem cell apoptosis in non-obese-diabetic/severe-combined-immunodeficiency mouse model. Impact statement Multiple myeloma (MM) remains largely incurable until now. One of the main reasons is that there are cancer stem cells (CSCs) in MM, which are responsible for MM's drug resistance and relapse. In this study, we wanted to extend our previous investigation²² that whether we developed the LCL-HHT-H-PEG formulation have an inhibitory effect on MM CD138^-CD34^-CSCs in MM CSC engrafted NOD/SCID mouse model. Our data from the present study have demonstrated the therapeutic effect of LCL-HHT-H-PEG on MM-bearing mouse model. The study represents the first attempt to demonstrate that the LCL-HHT-H-PEG formulation is available for treatment MM patients in clinic. Therefore, this finding is important and deserves publication in Experimental Biology and Medicine.

Intestinal permeation enhancers for oral peptide delivery

Intestinal permeation enhancers (PEs) are one of the most widely tested strategies to improve oral delivery of therapeutic peptides. This article assesses the intestinal permeation enhancement action of over 250 PEs that have been tested in intestinal delivery models. In depth analysis of pre-clinical data is presented for PEs as components of proprietary delivery systems that have progressed to clinical trials. Given the importance of co-presentation of sufficiently high concentrations of PE and peptide at the small intestinal epithelium, there is an emphasis on studies where PEs have been formulated with poorly permeable molecules in solid dosage forms and lipoidal dispersions.