Dihydrocapsaicin suppresses proinflammatory cytokines expression by enhancing nuclear factor IA in a NF-κB-dependent manner

Sweet Bell Pepper: A Focus on Its Nutritional Qualities and Illness-Alleviated Properties

Sweet bell pepper (SBP, Capsicum annuum L.) can be employed as a spice in many dishes and may also be eaten as a delicious fruit. These two nutritional attributes are owing to the strong, deep taste of many SBP phytochemicals. This fruit has many additional beneficial properties because it contains high concentrations of minerals and vitamins that distinguish it from other kinds of fruits. Almost every part of the SBP is thought to be an excellent source of bioactive substances that are health supporters, such as flavonoids, polyphenols, and various aromatic substances. The ability of SBP-phytochemicals to work as antioxidants, reducing the harmful effects of oxidative stress and consequently preventing many chronic illnesses, is one of their main biomedical characteristics. These phytochemicals have good antibacterial properties, mostly against gram-positive pathogenic microbes, in addition to their anti-carcinogenic and cardio-preventive effects. So, this review aims to highlight the nutritional qualities of SBP-derived phytochemicals and their illness-alleviated characteristics. Antioxidant, anti-inflammatory, antitumor, antidiabetic, and analgesic properties are some of the ones discussed.

Diversity and heterogeneity in human breast cancer adipose tissue revealed at single-nucleus resolution

Introduction

There is increasing awareness of the role of adipose tissue in breast cancer occurrence and development, but no comparison of adipose adjacent to breast cancer tissues and adipose adjacent to normal breast tissues has been reported.

Methods

Single-nucleus RNA sequencing (snRNA-seq) was used to analyze cancer-adjacent and normal adipose tissues from the same breast cancer patient to characterize heterogeneity. SnRNA-seq was performed on 54513 cells from six samples of normal breast adipose tissue (N) distant from the tumor and tumor-adjacent adipose tissue (T) from the three patients (all surgically resected).

Results and discussion

Significant diversity was detected in cell subgroups, differentiation status and, gene expression profiles. Breast cancer induces inflammatory gene profiles in most adipose cell types, such as macrophages, endothelial cells, and adipocytes. Furthermore, breast cancer decreased lipid uptake and the lipolytic phenotype and caused a switch to lipid biosynthesis and an inflammatory state in adipocytes. The in vivo trajectory of adipogenesis revealed distinct transcriptional stages. Breast cancer induced reprogramming across many cell types in breast cancer adipose tissues. Cellular remodeling was investigated by alterations in cell proportions, transcriptional profiles and cell-cell interactions. Breast cancer biology and novel biomarkers and therapy targets may be exposed.

Beneficial effects of capsaicin and dihydrocapsaicin on endothelial inflammation, nitric oxide production and antioxidant activity

Capsaicin and dihydrocapsaicin (DHC) are major pungent capsaicinoids produced in chili peppers. Capsaicin has been previously shown to promote vascular health by increasing nitric oxide (NO) production and reducing inflammatory responses. While capsaicin has been extensively studied, whether DHC exerts cardiovascular benefits through similar mechanisms remains unclear. The current study aimed to investigate the direct effects of DHC on endothelial inflammation, NO release, and free radical scavenging properties. DHC at concentrations up to 50 µM did not affect cell viability, while concentrations of 100 and 500 µM of DHC led to endothelial cytotoxicity. Capsaicin decreased cell viability at concentration of 500 µM. To investigate the effects of capsaicinoids on endothelial activation, we first demonstrated that TNFα induced Ser536 phosphorylation of p65 NFκB, expressions of adhesion molecules, vascular cell adhesion molecule (VCAM)-1 and intercellular adhesion molecule (ICAM)-1, and IL-6 production in primary human endothelial cells. These effects were robustly abrogated by DHC. Consistently, DHC treatment led to a marked reduction in TNFα-mediated monocyte adhesion to endothelial cells. Additionally, NO production was significantly induced by DHC and capsaicin compared to vehicle control. Similar to capsaicin and vitamin C, DHC scavenged DPPH (1,1-diphenyl-2-picrylhydrazyl) free radicals in vitro. Our present study highlights the benefits of DHC and capsaicin treatment on human endothelial cells and provides evidence to support cardiovascular benefits from capsicum consumption.

MicroRNA-361-5p Aggravates Acute Pancreatitis by Promoting Interleukin-17A Secretion via Impairment of Nuclear Factor IA-Dependent Hes1 Downregulation

This study set out to explore the potential role of microRNA-361-5p (miR-361-5p) in acute pancreatitis through regulation of interleukin-17A (IL-17A). We first identified the expression of miR-361-5p, IL-17A, nuclear factor IA (NFIA), and hes family bHLH transcription factor 1 (Hes1) in serum samples collected from patients with acute pancreatitis, caerulein-induced mice, and a Th17 cell model. The predicted binding of miR-361-5p to NFIA was confirmed in vitro. Gain- and loss-of-function assays of miR-361-5p and NFIA were employed to elucidate their effects on acute pancreatitis. miR-361-5p promoted Th17 cells to secrete IL-17A and then aggravated acute pancreatitis. miR-361-5p directly targeted NFIA by binding to its promoter region, leading to its downregulation. Overexpression of NFIA reduced Hes1 expression and rescued the promoting effect of miR-361-5p on IL-17A secretion. In summary, miR-361-5p enhances IL-17A secretion from Th17 cells and thus aggravates acute pancreatitis by targeting NFIA and upregulating Hes1.

Anti-atherosclerotic Effects of Spice-Derived Phytochemicals

Cardiovascular diseases are the leading cause of death in the world. Atherosclerosis is characterized by oxidized lipid deposition and inflammation in the arterial wall and represents a significant problem in public health and medicine. Some dietary spices have been widely used in many countries; however, the mechanism of their action as it relates to the prevention and treatment of atherosclerosis is still poorly understood. In this review, we focus on the properties of various spice-derived active ingredients used in the prevention and treatment of atherosclerosis, as well as associated atherosclerotic risk factors. We provide a summary of the mechanisms of action, epidemiological analyses, and studies of various components of spice used in the clinic, animal models, and cell lines related to atherosclerosis. Most notably, we focused on mechanisms of action by which these spice-derived compounds elicit their lipid-lowering, anti-inflammatory, antioxidant, and immunomodulatory properties, as well as their involvement in selected biochemical and signal transduction pathways. It is suggested that future research should aim to design well-controlled clinical trials and more thoroughly investigate the role of spices and their active components in the prevention/treatment of atherosclerosis. Based on this literature review, it appears that spices and their active components are well tolerated and have few adverse side effects and, therefore, provide a promising adjunctive treatment strategy for patients with atherosclerosis.

Dihydrocapsaicin Inhibits Cell Proliferation and Metastasis in Melanoma via Down-regulating β-Catenin Pathway

Dihydrocapsaicin (DHC) is one of the main components of capsaicinoids in Capsicum. It has been reported that DHC exerts anti-cancer effects on diverse malignant tumors, such as colorectal cancer, breast cancer, and glioma. However, studies focused on the effect of DHC upon melanoma have rarely been done. In the present study, melanoma A375 and MV3 cell lines were treated with DHC and the cell proliferation, migration, and invasion were significantly suppressed. Furthermore, DHC effectively inhibited xenograft tumor growth and pulmonary metastasis of melanoma cells in NOD/SCID mice model. It was identified that β-catenin, which plays significant roles in cell proliferation and epithelial-mesenchymal transition, was down-regulated after DHC treatment. In addition, cyclin D1, c-Myc, MMP2, and MMP7, which are critical in diverse cellular process regulation as downstream proteins of β-catenin, were all decreased. Mechanistically, DHC accelerates ubiquitination of β-catenin and up-regulates the beta-transducin repeat containing E3 ubiquitin protein ligase (BTRC) in melanoma cells. The DHC induced suppression of cell proliferation, migration, and invasion were partly rescued by exogenous β-catenin overexpression, both in vitro and in vivo. Taken together, DHC may serve as a candidate natural compound for human melanoma treatment through β-catenin pathway.

Dysregulated microRNA expression in IL-4 transgenic mice, an animal model of atopic dermatitis

IL-4 plays an important role in the pathogenesis of atopic dermatitis (AD). Previously we showed that the expression of genes in chemotaxis, angiogenesis, inflammation and barrier functions is dysregulated in IL-4 transgenic (Tg) mice, a well-characterized AD mouse model. In this study, we aim to study differential expression of microRNAs in IL-4 Tg mice. As compared with wild-type mice, we found that 10 and 79 microRNAs are dysregulated in the skin of IL-4 mice before and after the onset of skin lesions, respectively. Bioinformatic analysis and previous reports show that these dysregulated microRNAs may be involved in the NF-κB, TLRs, IL-4/IL-13, MAPK and other pathways. We also found that miR-139-5p and miR-196b-3p are significantly up-regulated in the peripheral blood of IL-4 Tg mice. Taken together, our data have identified many dysregulated microRNAs in IL-4 Tg mice, which may play important roles in AD pathogenesis and pathophysiology.

Molecular cloning, expression and functional analysis of NF-kB1 p105 from sea cucumber Holothuria leucospilota

The nuclear factor-κB (NF-κB) family is evolutionary conserved and plays key roles in the regulation of numerous basic cellular processes. In this study, a sea cucumber Holothuria leucospilota NF-κB1 p105 named HLp105 was first obtained. The full-length cDNA of HLp105 is 6564 bp long, with a 219 bp 5' untranslated region (UTR), a 2979 bp 3' UTR, and a 3366 bp open reading frame (ORF) encoding for 1121 amino acids with a deduced molecular weight of 123.92 kDa and an estimated pI of 5.31. HLp105 protein contains the conserved domain RHD, IPT, ANK and DEATH. HLp105 mRNA can be detected in all tissues examined, with the highest level in the intestine, followed by the transverse vessel, rete mirabile, coelomocytes, respiratory tree, bolishiti, cuvierian tubules, body wall, oesophagus and muscle. Challenged by LPS or poly (I:C), the transcription level of HLp105 was apparently up-regulated in the tissues examined. Besides, Over-expression of HLp105 in HEK293T cells, the apoptosis was inhibited, and the cytokines IL-1β and TNF-α were activated. The results are important for better understanding the function of NF-κB1 p105 in sea cucumber and reveal its involvement in immunoreaction.

High mobility group nucleosomal binding 2 reduces integrin α5/β1-mediated adhesion of Klebsiella pneumoniae on human pulmonary epithelial cells via nuclear factor I

It has been reported that high mobility group nucleosomal binding domain 2 (HMGN2) is a nucleus-related protein that regulates gene transcription and plays a critical role in bacterial clearance. An elevated level of HMGN2 reduced integrin α5/β1 expression of human pulmonary epithelial A549 cells was demonstrated during Klebsiella pneumoniae infection, thus weakening bacterial adhesion and invasion. However, the mechanism by which HMGN2 regulates integrin expression remains unclear. This study found that a transcription factor-nuclear factor I (NFI), which serves as the potential target of HMGN2 regulated integrin expression. The results showed that HMGN2 was able to promote NFIA and NFIB expression by increasing H3K27 acetylation of NFIA/B promoter regions. The integrin α5/β1 expression was significantly enhanced by knockdown of NFIA/B via a siRNA approach. Meanwhile, NFIA/B silence could also compromise the inhibition effect of HMGN2 on the integrin α5/β1 expression. Mechanistically, it was demonstrated that HMGN2 facilitated the recruitment of NFI on the promoter regions of integrin α5/β1 according to the chromatin immunoprecipitation assay. In addition, it was further demonstrated that the knockdown of NFIA/B induced more adhesion of Klebsiella pneumoniae on pulmonary epithelial A549 cells, which could be reversed by the application of an integrin inhibitor RGD. The results revealed a regulatory role of HMGN2 on the transcription level of integrin α5/β1, indicating a potential treatment strategy against Klebsiella pneumoniae-induced infectious lung diseases.

MALAT1 overexpression attenuates AS by inhibiting ox-LDL-stimulated dendritic cell maturation via miR-155-5p/NFIA axis

MALAT1 is associated with dendritic cells (DCs) maturation in Atherosclerosis (AS). This article aims to demystify the role of MALAT1 in AS. We separated immature DCs (iDCs) from healthy volunteers or ApoE-/- mice. And iDCs were treated with oxidized low density lipoprotein (ox-LDL) to induce DCs maturation. We found that ox-LDL promoted the levels of DCs maturation markers including CD83, CD86, IL-12 and IL-6. MALAT1 and NFIA were down-regulated, whereas miR-155-5p was up-regulated in the ox-LDL-treated iDCs. Furthermore, DCs maturation was notably suppressed by MALAT1 overexpression, NFIA overexpression or miR-155-5p knockdown. Moreover, MALAT1 functioned as a competing endogenous RNA to repress miR-155-5p, which controlled its down-stream target, NFIA. In addition, MALAT1 overexpression inhibited ox-LDL-stimulated DCs maturation by regulating miR-155-5p/NFIA axis. In AS mice, MALAT1 overexpression attenuated ox-LDL-stimulated DCs maturation and reduced atherosclerotic plaque area. In summary, our study demonstrates that MALAT1 overexpression attenuates AS by inhibiting ox-LDL-stimulated DCs maturation via miR-155-5p/NFIA axis. Thus, MALAT1/miR-155-5p/NFIA axis can potentially be used in the treatment of AS.

Capsaicin-Sensitive Sensory Nerves and the TRPV1 Ion Channel in Cardiac Physiology and Pathologies

Cardiovascular diseases, including coronary artery disease, ischemic heart diseases such as acute myocardial infarction and postischemic heart failure, heart failure of other etiologies, and cardiac arrhythmias, belong to the leading causes of death. Activation of capsaicin-sensitive sensory nerves by the transient receptor potential vanilloid 1 (TRPV1) capsaicin receptor and other receptors, as well as neuropeptide mediators released from them upon stimulation, play important physiological regulatory roles. Capsaicin-sensitive sensory nerves also contribute to the development and progression of some cardiac diseases, as well as to mechanisms of endogenous stress adaptation leading to cardioprotection. In this review, we summarize the role of capsaicin-sensitive afferents and the TRPV1 ion channel in physiological and pathophysiological functions of the heart based mainly on experimental results and show their diagnostic or therapeutic potentials. Although the actions of several other channels or receptors expressed on cardiac sensory afferents and the effects of TRPV1 channel activation on different non-neural cell types in the heart are not precisely known, most data suggest that stimulation of the TRPV1-expressing sensory nerves or stimulation/overexpression of TRPV1 channels have beneficial effects in cardiac diseases.

Upregulation of Nuclear Factor IA Suppresses Oxidized Low-Density Lipoprotein-Induced Endoplasmic Reticulum Stress and Apoptosis in Human Umbilical Vein Endothelial Cells

Background

Endoplasmic reticulum stress (ERS) is part of the cardiovascular pathological processes, including atherosclerosis. Nuclear factor IA (NFIA) influences atherosclerosis development; however, its effects on ERS remain unknown. This study investigated the effect of NFIA on oxidized low-density lipoprotein (ox-LDL)-induced ERS and apoptosis in endothelial cells.

Material/Methods

Ox-LDL was used to induce lipotoxicity in human umbilical vein endothelial cells (HUVECs) to establish an in vitro oxidative injury model transfected with pcDNA3.0-NFIA. The cytotoxic response was detected using an assay to determine the release of lactate dehydrogenase (LDH). Morphological changes in cell apoptosis were detected using Hoechst 33258 staining. The proportion of apoptotic cells, releases of reactive oxygen species (ROS), and mitochondrial membrane potential (ΔΨm) were determined using flow cytometry. The expression levels of apoptosis- and ERS-related molecules were detected through Western blotting.

Results

NFIA expression was downregulated in the in vitro oxidative cell-injury model. Exposure of HUVECs to ox-LDL resulted in a significant increase in apoptosis, decrease in ROS levels, and loss of ΔΨm. Overexpression of NFIA remarkably inhibited ERS and mitochondrial-mediated apoptosis induced by ox-LDL in HUVECs by reversing the effect of ox-LDL on the expression of JNK1, p-JNK1, CHOP, Cyt C, and Bax.

Conclusions

These results demonstrated that NFIA might have beneficial effects in the prevention of ox-LDL-induced ERS and apoptosis in vascular endothelial cells. This study provided new insights into the mechanism of atherosclerosis.

Development of A New Delivery System Based on Drug-Loadable Electrospun Nanofibers for Psoriasis Treatment

Psoriasis is a chronic autoimmune systemic disease with an approximate incidence of 2% worldwide; it is commonly characterized by squamous lesions on the skin that present the typical pain, stinging, and bleeding associated with an inflammatory response. In this work, poly(methyl vinyl ether-alt-maleic ethyl monoester) (PMVEMA-ES) nanofibers have been designed as a delivery vehicle for three therapeutic agents with palliative properties for the symptoms of this disease (salicylic acid, methyl salicylate, and capsaicin). For such a task, the production of these nanofibers by means of the electrospinning technique has been optimized. Their morphology and size have been characterized by optical microscopy and scanning electron microscopy (SEM). By selecting the optimal conditions to achieve the smallest and most uniform nanofibers, approximate diameters of up to 800⁻900 nm were obtained. It was also determined that the therapeutic agents that were used were encapsulated with high efficiency. The analysis of their stability over time by GC-MS showed no significant losses of the encapsulated compounds 15 days after their preparation, except in the case of methyl salicylate. Likewise, it was demonstrated that the therapeutic compounds that were encapsulated conserved, and even improved, their capacity to activate the transient receptor potential cation channel 1 (TRPV1) channel, which has been associated with the formation of psoriatic lesions.

Inflammatory cytokines are involved in dihydrocapsaicin (DHC) and regional cooling infusion (RCI)-induced neuroprotection in ischemic rat

OBJECTIVE

The combination of pharmacological hypothermia - dihydrocapsaicin (DHC) and intra-arterial regional cooling infusions (RCI) was found to enhance the efficiency of hypothermia and efficacy of hypothermia-induced neuroprotection in acute ischemic stroke. The aim of this study was to explore whether the combination could induce a long-term neuroprotective effects, as well as the underlying mechanism.

METHODS

Sprague-Dawley rats were subjected to middle cerebral artery occlusion (MCAO) for 2 h using intraluminal hollow filament. The ischemic rats were randomized to receive pharmacological hypothermia by intraperitoneal (i.p.) injection of DHC, physical hypothermia by RCI of 6 ml cold saline (4 °C), the combination, and no treatment. Over a 21-day period, brain damage was determined by infarct volume with MRI, and neurological deficit with grid-walking and beam balance tests. Blood brain barrier (BBB) was assessed by Evans-Blue (EB) contents. Inflammatory cytokines were determined in peri-infarct area by antibody array and ELISA.

RESULTS

The combination of DHC and RCI reduced (p < 0.05) infarct volume and neurologic deficit after stroke. BBB leakage and pro-inflammatory cytokines (IFN-γ, IL-2, and TNF-α) were significantly decreased (p < 0.05) because of the combination, while protective cytokines (IL-4 and IL-10) were increased (p < 0.05) in the peri-infarct area.

CONCLUSIONS

The combination approach enhanced the efficacy of hypothermia-induced neuroprotection following ischemic stroke. Our findings provide a hint to translate the combination method from bench to bedside.

TRPV1 mediates capsaicin-stimulated metabolic activity but not cell death or inhibition of interleukin-1β release in human THP-1 monocytes

Human monocytes and dendritic cells express transient receptor potential vanilloid 1 (TRPV1) which may play a role in mediating the inflammatory, immune and cancer surveillance responses of these cells. The aim of the present study was to investigate TRPV1 expression and function in THP-1 monocytic cells. RT-PCR and Western blot were used to detect TRPV1. The metabolic activity and viability of THP-1 cells following exposure to vanilloids was assessed using resorufin production from rezazurin. Cytokine release was measured using ELISA. TRPV1 was expressed in cultured THP-1 monocytic cells and naïve monocytes. Lower concentrations (<250 μM) of capsaicin, but not other putative TRPV1 agonists, were shown to stimulate cell metabolic activity, whereas at concentrations >250 μM, all agonists decreased metabolic activity. Capsaicin-stimulated THP-1 metabolic activity was blocked by the TRPV1 antagonist, 5-iodo-resiniferatoxin (5'-IRTX), whereas the decline in resorufin production by THP-1 cells at higher capsaicin concentrations (due to cell death), was not affected by 5'-IRTX. Finally, capsaicin (≤125 μM) significantly increased lipopolysaccharide-stimulated IL-6 and TNF-α release from THP-1 cells, whereas phytohaemagglutinin-stimulated IL-1β, TNF-α, MCP-1 and IL-6 release were concentration-dependently inhibited by capsaicin. Modulation of IL-1β release was not TRPV1 mediated. Overall, these results show that functional TRPV1 channels are present in naïve monocytes and THP-1 cells, and when activated, increase cell metabolic activity. In addition, capsaicin modifies cytokine release from THP-1 cells and induces cell death, most likely by a mechanism that is independent of TRPV1 activation.

Dihydrocapsaicin Attenuates Blood Brain Barrier and Cerebral Damage in Focal Cerebral Ischemia/Reperfusion via Oxidative Stress and Inflammatory

This study investigated the effect of dihydrocapsaicin (DHC) on cerebral and blood brain barrier (BBB) damage in cerebral ischemia and reperfusion (I/R) models. The models were induced by middle cerebral artery occlusion (MCAO) for 2 h followed by reperfusion. The rats were divided into five groups: sham, or control group; vehicle group; and 2.5 mg/kg, 5 mg/kg, and 10 mg/kg BW DHC-treated I/R groups. After 24 h of reperfusion, we found that DHC significantly reduced the area of infarction, morphology changes in the neuronal cells including apoptotic cell death, and also decreased the BBB damage via reducing Evan Blue leakage, water content, and ultrastructure changes, in addition to increasing the tight junction (TJ) protein expression. DHC also activated nuclear-related factor-2 (Nrf2) which involves antioxidant enzymes like superoxide dismutase (SOD) and glutathione peroxidase (GPx), and significantly decreased oxidative stress and inflammation via down-regulated reactive oxygen species (ROS), NADPH oxidase (NOX2, NOX4), nuclear factor kappa-beta (NF-ĸB), and nitric oxide (NO), including matrix metalloproteinases-9 (MMP-9) levels. DHC protected the cerebral and the BBB from I/R injury via attenuation of oxidative stress and inflammation. Therefore, this study offers to aid future development for protection against cerebral I/R injury in humans.