A Quantity-Dependent Nonlinear Model of Sodium Cromoglycate Suppression on Beta-Conglycinin Transport.

Understanding the transport mechanism is crucial for developing inhibitors that block allergen absorption and transport and prevent allergic reactions. However, the process of how beta-conglycinin, the primary allergen in soybeans, crosses the intestinal mucosal barrier remains unclear. The present study indicated that the transport of beta-conglycinin hydrolysates by IPEC-J2 monolayers occurred in a time- and quantity-dependent manner. The beta-conglycinin hydrolysates were absorbed into the cytoplasm of IPEC-J2 monolayers, while none were detected in the intercellular spaces. Furthermore, inhibitors such as methyl-beta-cyclodextrin (MßCD) and chlorpromazine (CPZ) significantly suppressed the absorption and transport of beta-conglycinin hydrolysates. Of particular interest, sodium cromoglycate (SCG) exhibited a quantity-dependent nonlinear suppression model on the absorption and transport of beta-conglycinin hydrolysates. In conclusion, beta-conglycinin crossed the IPEC-J2 monolayers through a transcellular pathway, involving both clathrin-mediated and caveolae-dependent endocytosis mechanisms. SCG suppressed the absorption and transport of beta-conglycinin hydrolysates by the IPEC-J2 monolayers by a quantity-dependent nonlinear model via clathrin-mediated and caveolae-dependent endocytosis. These findings provide promising targets for both the prevention and treatment of soybean allergies.

Disodium Cromoglycate Templates Anisotropic Short-Chain PEG Hydrogels.

Anisotropic hydrogels have found widespread applications in biomedical engineering, particularly as scaffolds for tissue engineering. However, it remains a challenge to produce them using conventional fabrication methods, without specialized synthesis or equipment, such as 3D printing and unidirectional stretching. In this study, we explore the self-assembly behaviors of polyethylene glycol diacrylate (PEGDA), using disodium cromoglycate (DSCG), a lyotropic chromonic liquid crystal, as a removable template. The affinity between short-chain PEGDA (Mn = 250) and DSCG allows polymerization to take place at the DSCG surface, thereby forming anisotropic hydrogel networks with fibrin-like morphologies. This process requires considerable finesse as the phase behaviors of DSCG depend on a multitude of factors, including the weight percentage of PEGDA and DSCG, the chain length of PEGDA, and the concentration of ionic species. The key to modulating the microstructures of the all-PEG hydrogel networks is through precise control of the DSCG concentration, resulting in anisotropic mechanical properties. Using these anisotropic hydrogel networks, we demonstrate that human dermal fibroblasts are particularly sensitive to the alignment order. We find that cells exhibit a density-dependent activation pattern of a Yes-associated protein, a mechanotransducer, corroborating its role in enabling cells to translate external mechanical and morphological patterns to specific behaviors. The flexibility of modulating microstructure, along with PEG hydrogels' biocompatibility and biodegradability, underscores their potential use for tissue engineering to create functional structures with physiological morphologies.

Luteolin Is More Potent than Cromolyn in Their Ability to Inhibit Mediator Release from Cultured Human Mast Cells.

INTRODUCTION: Mast cells are known for their involvement in allergic reactions but also in inflammatory reactions via secretion of numerous pro-inflammatory chemokines, cytokines, and enzymes. Drug development has focused on antiproliferative therapy for systemic mastocytosis and not on inhibitors of mast cell activation. The only drug available as a "mast cell blocker" is disodium cromoglycate (cromolyn), but it is poorly absorbed after oral administration, is a weak inhibitor of histamine release from human mast cells, and it develops rapid anaphylaxis. Instead, certain natural flavonoids, especially luteolin, can inhibit mast cell activation. METHODS: Here, we compared pretreatment (0-120 min) with equimolar concentration (effective dose for 50% inhibition = 100 mm for inhibition of histamine release by cromolyn) of cromolyn and luteolin on release of mediators from the cultured human LADR mast cell line stimulated either by immunoglobulin E (IgE) and anti-IgE or with IL-33. RESULTS: We show that luteolin is significantly more potent than cromolyn inhibiting release of histamine, tryptase, metalloproteinase-9, and vascular endothelial growth factor. Moreover, while luteolin also significantly inhibited release of IL-1ß, IL-6, and IL-8 (CXCL8) and TNF, cromolyn had no effect. CONCLUSION: These findings support the use of luteolin, especially in liposomal form to increase oral absorption, may be a useful alternative to cromolyn.

Recruitment or activation of mast cells in the liver aggravates the accumulation of fibrosis in carbon tetrachloride-induced liver injury.

Liver diseases caused by viral infections, alcoholism, drugs, or chemical poisons are a significant health problem: Liver diseases are a leading contributor to mortality, with approximately 2 million deaths per year worldwide. Liver fibrosis, as a common liver disease characterized by excessive collagen deposition, is associated with high morbidity and mortality, and there is no effective treatment. Numerous studies have shown that the accumulation of mast cells (MCs) in the liver is closely associated with liver injury caused by a variety of factors. This study investigated the relationship between MCs and carbon tetrachloride (CCl4)-induced liver fibrosis in rats and the effects of the MC stabilizers sodium cromoglycate (SGC) and ketotifen (KET) on CCl4-induced liver fibrosis. The results showed that MCs were recruited or activated during CCl4-induced liver fibrosis. Coadministration of SCG or KET alleviated the liver fibrosis by decreasing SCF/c-kit expression, inhibiting the TGF-ß1/Smad2/3 pathway, depressing the HIF-1a/VEGF pathway, activating Nrf2/HO-1 pathway, and increasing the hepatic levels of GSH, GSH-Px, and GR, thereby reducing hepatic oxidative stress. Collectively, recruitment or activation of MCs is linked to liver fibrosis and the stabilization of MCs may provide a new approach to the prevention of liver fibrosis.

Promising anticancer activity of cromolyn in colon cancer: in vitro and in vivo analysis.

PURPOSE: Colon cancer is a prevalent cancer globally, representing approximately 10% of all cancer cases and accounting for 10% of all cancer-related deaths. Therefore, finding new therapeutic methods with high efficiency will be very valuable. Cromolyn (C), a common anti-allergic and mast cell membrane stabilizing drug, has recently shown valuable anti-cancer effects in several studies. This study was designed to investigate the anti-cancer activity of cromolyn on colon cancer in vitro and in vivo and to determine values such as selectivity index and survival effect. METHODS: HT-29 (colon cancer) and MCF-10 (normal epithelial) cell lines were treated with C and Doxorubicin (DOX; Positive control). IC50 values and the effects of C and DOX on apoptosis were explored using methyl thiazole diphenyl-tetrazolium bromide (MTT) assay and Annexin V/PI Apoptosis Assay Kit. To investigate in an animal study, colon cancer was subcutaneously induced by CT26 cells (mouse colon cancer) in bulb/c mice. Mice were treated with 0.05 LD50 intraperitoneal every other day for 35 days. After the death of mice, tumor volume, tumor weight, and survival rate were evaluated. RESULTS: C selectively and significantly suppressed the proliferation of cancer cells in a dose-dependent manner. The IC50 values for the MCF-10 and HT29 cell lines were 7.33 ± 0.78 µM and 2.33 ± 0.6 µM, respectively. Notably, the selective index (SI) highlighted that C displayed greater selectivity in inhibiting cancer cell growth compared to DOX, with SI values of 3.15 and 2.60, respectively. C exhibited higher effectiveness and selectivity in inducing apoptosis in cancer cells compared to DOX, with a significant p-value (61% vs. 52%, P-value ≤ 0.0001). Also, in mice bearing colon cancer, C reduced the tumor volume (6317 ± 1685mm3) and tumor weight (9.8 ± 1.6 g) compared to the negative control group (weight 12.45 ± 0.9 g; volume 7346 ± 1077) but these values were not statistically significant (P ≤ 0.05). CONCLUSION: Our study showed that cromolyn is a selective and strong drug in inhibiting the proliferation of colon cancer cells. Based on our results, the efficacy of C in vitro analysis (MTT assays and apoptosis), as well as animal studies is competitive with the FDA-approved drug doxorubicin. C is very promising as a low-complication and good-efficacy drug for cancer drug repositioning. This requires clinical research study designs to comprehensively evaluate its anti-cancer effects.

Suppression of Mast Cell Activation by GPR35: GPR35 Is a Primary Target of Disodium Cromoglycate.

Mast cell stabilizers, including disodium cromoglycate (DSCG), were found to have potential as the agonists of an orphan G protein-coupled receptor, GPR35, although it remains to be determined whether GPR35 is expressed in mast cells and involved in suppression of mast cell degranulation. Our purpose in this study is to verify the expression of GPR35 in mast cells and to clarify how GPR35 modulates the degranulation. We explored the roles of GPR35 using an expression system, a mast cell line constitutively expressing rat GPR35, peritoneal mast cells, and bone marrow-derived cultured mast cells. Immediate allergic responses were assessed using the IgE-mediated passive cutaneous anaphylaxis (PCA) model. Various known GPR35 agonists, including DSCG and newly designed compounds, suppressed IgE-mediated degranulation. GPR35 was expressed in mature mast cells but not in immature bone marrow-derived cultured mast cells and the rat mast cell line. Degranulation induced by antigens was significantly downmodulated in the mast cell line stably expressing GPR35. A GPR35 agonist, zaprinast, induced a transient activation of RhoA and a transient decrease in the amount of filamentous actin. GPR35 agonists suppressed the PCA responses in the wild-type mice but not in the GPR35-/- mice. These findings suggest that GPR35 should prevent mast cells from undergoing degranulation induced by IgE-mediated antigen stimulation and be the primary target of mast cell stabilizers. SIGNIFICANCE STATEMENT: The agonists of an orphan G protein-coupled receptor, GPR35, including disodium cromoglycate, were found to suppress degranulation of rat and mouse mature mast cells, and their antiallergic effects were abrogated in the GPR35-/- mice, indicating that the primary target of mast cell stabilizers should be GPR35.

Combined effect of trifluoperazine and sodium cromoglycate on reducing acute edema and limiting lasting functional impairments after spinal cord injury in rats.

Edema formation is one of the very first events to occur after spinal cord injury (SCI) leading to an increase of the intrathecal pressure and consequently to serious spinal tissue and functional impairments. Current edema treatments are still symptomatic and/or non-specific. Since edema formation mechanisms are mainly described as vasogenic and cytotoxic, it becomes crucial to understand the interplay between these two subtypes. Acting on key targets to inhibit edema formation may reduce secondary damage and related functional impairments. In this study, we characterize the edema kinetic after T9-10 spinal contusion. We use trifluoperazine (TFP) to block the expression and the functional subcellular localization of aquaporin-4 supposed to be implicated in the cytotoxic edema formation. We also use sodium cromoglycate (SCG) to deactivate mast cell degranulation known to be implicated in the vasogenic edema formation. Our results show a significant reduction of edema after TFP treatment and after TFP-SCG combined treatment compared to control. This reduction is correlated with limited onset of initial sensorimotor impairments particularly after combined treatment. Our results highlight the importance of potential synergetic targets in early edema therapy after SCI as part of tissue sparing strategies.

Stabilizing histamine release in gut mast cells mitigates peripheral and central inflammation after stroke.

Stroke is the most common cause of long-term disability and places a high economic burden on the global healthcare system. Functional outcomes from stroke are largely determined by the extent of ischemic injury, however, there is growing recognition that systemic inflammatory responses also contribute to outcomes. Mast cells (MCs) rapidly respond to injury and release histamine (HA), a pro-inflammatory neurotransmitter that enhances inflammation. The gut serves as a major reservoir of HA. We hypothesized that cromolyn, a mast cell stabilizer that prevents the release of inflammatory mediators, would decrease peripheral and central inflammation, reduce MC trafficking to the brain, and improve stroke outcomes. We used the transient middle cerebral artery occlusion (MCAO) model of ischemic stroke in aged (18 mo) male mice to investigate the role of MC in neuroinflammation post-stroke. After MCAO we treated mice with 25 mg/kg body weight of cromolyn (MC stabilizer) by oral gavage. Cromolyn was administered at 3 h, 10 h, 24 h and every 24 h for 3 days post-stroke. Three control groups were used. One group underwent a sham surgery and was treated with cromolyn, one received sham surgery with PBS vehicle and the third underwent MCAO with PBS vehicle. Mice were euthanized at 24 h and 3 days post-stroke. Cromolyn administration significantly reduced MC numbers in the brain at both 24 h and 3 days post-stroke. Infarct volume was not significantly different between groups, however improved functional outcomes were seen at 3 days post-stroke in mice that received cromolyn. Treatment with cromolyn reduced plasma histamine and IL-6 levels in both the 24-h and 3-day cohorts. Gut MCs numbers were significantly reduced after cromolyn treatment at 24 h and 3 days after stroke. To determine if MC trafficking from the gut to the brain occurred after injury, GFP+MCs were adoptively transferred to c-kit-/- MC knock-out animals prior to MCAO. 24 h after stroke, elevated MC recruitment was seen in the ischemic brain. Preventing MC histamine release by cromolyn improved gut barrier integrity and an improvement in stroke-induced dysbiosis was seen with treatment. Our results show that preventing MC histamine release possesses prevents post-stroke neuroinflammation and improves neurological and functional outcomes.

The Interactions of Magnesium Sulfate and Cromoglycate in a Rat Model of Orofacial Pain; The Role of Magnesium on Mast Cell Degranulation in Neuroinflammation.

Mast cell degranulation impacts the development of pain and inflammation during tissue injury. We investigated the antinociceptive effect of a combination of cromoglycate and magnesium in the orofacial model of pain and the histological profile of the effect of magnesium in orofacial pain. In male Wistar rats, formalin (1.5%, 100 µL) was injected subcutaneously into the right upper lip of rats after cromoglycate and/or magnesium. Pain was measured as the total time spent on pain-related behavior. Toluidine blue staining was used to visualize mast cells under the light microscope. In the formalin test, in phase 1, magnesium antagonized the antinociceptive effect of cromoglycate, while in phase 2, it potentiated or inhibited its effect. Magnesium significantly reduced mast cell degranulation in the acute phase by about 23% and in the second phase by about 40%. Pearson's coefficient did not show a significant correlation between mast cell degranulation and pain under treatment with magnesium. The cromoglycate-magnesium sulfate combination may prevent the development of inflammatory orofacial pain. The effect of a combination of cromoglycate-magnesium sulfate depends on the nature of the pain and the individual effects of the drugs. Magnesium reduced orofacial inflammation in the periphery, and this effect did not significantly contribute to its analgesic effect.

Degranulation of Murine Resident Cochlear Mast Cells: A Possible Factor Contributing to Cisplatin-Induced Ototoxicity and Neurotoxicity.

Permanent hearing loss is one of cisplatin's adverse effects, affecting 30-60% of cancer patients treated with that drug. Our research group recently identified resident mast cells in rodents' cochleae and observed that the number of mast cells changed upon adding cisplatin to cochlear explants. Here, we followed that observation and found that the murine cochlear mast cells degranulate in response to cisplatin and that the mast cell stabilizer cromoglicic acid (cromolyn) inhibits this process. Additionally, cromolyn significantly prevented cisplatin-induced loss of auditory hair cells and spiral ganglion neurons. Our study provides the first evidence for the possible mast cell participation in cisplatin-induced damage to the inner ear.

The Investigation of Therapeutic Implications of Mast Cell Stabilizer Cromolyn Sodium on Cholestasis and Cholestatic Pruritus in Experimental Cholestasis.

BACKGROUND: Relevant studies have indicated that hepatic mast cells may have potential roles in the progression of cholestasis and cholestasis-induced itch. We aimed to compare the effects of cromolyn sodium and other medications on cholestatic pruritus, serum biochemistry, histamine, total bile acids, autotaxin, liver histopathology, and mast cell distribution in tissues in an experimental cholestasis model conducted by bile duct ligation. METHODS: Rats received the determined treatment consecutively for 10 days in addition to bile duct ligation. On the 5th and 10th days of the experiment, the rats' itching behaviors were observed for 5 minutes. After 10 days, blood and tissue samples were taken. RESULTS: Significant decreases in serum histamine and autotaxin levels, plasma total bile acids, total bilirubin, and biliary enzymes were reported only in cromolyn sodium-treated rats compared to the control group. In immunohistochemistry of the liver samples, the peribiliary mast cells stained positive for autotaxin. Except for bile duct infarctus, all histopathological findings of cholestasis significantly improved only in cromolyn sodium-treated and sertraline-treated rats. The liver and peritoneal mast cells significantly decreased only in cromolyn sodium-treated rats compared to the control group. On the 10th day of the experiment, the mean duration of itching was significantly lower in all groups, except for naloxone- and ondansetron-treated rats. CONCLUSION: Cromolyn sodium has promising antipruritic efficacy and provides biochemical and histopathological recovery of the relevant parameters of cholestasis induced by bile duct ligation. For the first time in the literature, we showed that peribiliary mast cells can produce autotaxin, which is a very important pruritogenic signal in the setting of cholestasis.

PD-1+ mast cell enhanced by PD-1 blocking therapy associated with resistance to immunotherapy.

BACKGROUND: Programmed cell death protein 1 (PD-1) antibody has been approved for a variety of tumors, but its effective rate is unsatisfactory. New evidence suggests that mast cells are an important component of the tumor microenvironment and are associated with resistance to immunotherapy, but the underlying mechanism is not clear. METHODS: Bioinformatics analysis of patients with melanoma in TCGA-SKCM and GSE91061 was used to determine the prognostic value of mast cells and their association with anti-PD-1 immunotherapy. HMC-1 cells (mast cell line) and bone marrow-derived mast cells (BMMCs) were used to verify the effect of PD-1 antibody and cromolyn sodium in vitro. The mouse subcutaneous melanoma model was used to verify the effect of the PD-1 antibody on mast cells in vivo. RESULTS: Bioinformatics analysis showed that mast cells were a poor prognostic factor associated with resistance to anti-PD-1 immunotherapy. PD-1 was expressed on the mast cell membrane. The PD-1 antibody promoted the release of histamine and cytokines from mast cells via the PI3K/AKT pathway and calcium signaling pathway. The activation of mast cells induced by PD-1 antibody could be partially inhibited by cromolyn sodium. In vivo, cromolyn sodium increased the efficacy of PD-1 antibody and decreased the infiltration of mast cells and the density of microvessels. CONCLUSION: PD-1+ mast cell activated by PD-1 antibody plays a negative role in the tumor microenvironment via the enhanced function of releasing histamine and cytokines. Inhibition of mast cell may provide a new solution to solve the low response rate of anti-PD-1 immunotherapy.

Cromolyn chitosan nanoparticles reverse the DNA methylation of RASSF1A and p16 genes and mitigate DNMT1 and METTL3 expression in breast cancer cell line and tumor xenograft model in mice.

BACKGROUND: Developing epigenetic drugs for breast cancer (BC) remains a novel therapeutic approach. Cromolyn is a mast cell stabilizer emerging as an anticancer drug; its encapsulation in chitosan nanoparticles (CSNPs) improves its effect and bioavailability. However, its effect on DNA and RNA methylation machineries has not been previously tackled. METHODS: The possible anticancer effect of cromolyn CSNPs and its potential as an epigenetic drug was investigated in vitro using MCF-7 human BC cell line and in vivo using Ehrlich ascites carcinoma-xenograft model in mice symbolizing murine mammary adenocarcinoma. Mice were injected with a single dose of Ehrlich ascites carcinoma cells subcutaneously for the induction of tumor mass, and then randomized into three groups: control, cromolyn CSNPs (equivalent to 5 mg cromolyn/kg, i.p.) and plain CSNPs twice/week for 2 weeks. RESULTS: Cromolyn CSNPs showed prominent anticancer effect in MCF-7 cells by reducing the cell viability percent and enhancing DNA damage in the comet assay demonstrating its apoptotic actions. Mechanistically, cromolyn CSNPs influenced potential epigenetic processes through mitigating DNA methyltransferase 1 (DNMT1) expression, reversing the hypermethylation pattern of the tumor suppressor RASSF1A and p16 genes and attenuating the expression of the RNA N6-methyladenosine writer, methyltransferase-like 3 (METTL3). Cromolyn CSNPs diminished ERK1/2 phosphorylation, a possible arm influencing DNMT1 expression. In vivo, cromolyn CSNPs lessened the tumor volume and halted DNMT1 and METTL3 expression in Ehrlich carcinoma mice. CONCLUSIONS: Cromolyn CSNPs have the premise as an epigenetic drug through inhibiting ERK1/2 phosphorylation/DNMT1/DNA methylation and possibly impacting the RNA methylation machinery via mitigating METTL3 expression.

Cromolyn Sodium differentially regulates human mast cell and mouse leukocyte responses to control allergic inflammation.

BACKGROUND: Cromolyn Sodium (CS) has been used in the past as an anti-allergy drug owing to its mast cell (MC) stabilizing properties that impair histamine release. However, additional mechanisms for its clinical actions are likely and might help to identify new roles for MCs and leukocytes in regulating inflammation. Here, using human cord blood-derived MCs (CBMCs), mouse bone marrow-derived MCs (BMMCs) and eosinophils (BMEos), and in vivo mouse models of allergic inflammation (AI), additional actions of CS on MCs were determined. METHODS: The in vitro effects of CS on IgE-activated human and mouse MCs were assessed by measuring the levels of pro-inflammatory (tryptase, LTC4, IL-8, CD48) and pro-resolution effectors (IL-10, CD300a, Annexin A1) before and after CS treatment. The in vivo effects of daily CS injections on parameters of inflammation were assessed using mouse models of allergic peritonitis (AP) (Ovalbumin/Alum- or Ovalbumin/S. aureus enterotoxin B) and allergic airways inflammation (AAI) (house dust mite (HDM)). RESULTS: In vitro, CS did not affect pro-inflammatory effectors but significantly increased the anti-inflammatory/pro-resolution CD300a levels and IL-10 release from IgE-activated CBMCs. BMMCs were not affected by CS. In vivo, CS injections decreased total cell and Eos numbers in the peritoneal cavity in the AP models and bronchoalveolar lavage and lungs in the AAI model. CS reduced EPX release from PAF-activated BMEos in vitro, possibly explaining the in vivo findings. CONCLUSION: Together, these results demonstrate immunomodulatory actions for CS in AI that are broader than only MC stabilization.

Effects of Disodium Cromoglycate Treatment in the Early Stage of Diabetic Nephropathy: Focus on Collagen Deposition.

Inflammation is part of the pathophysiology of diabetic nephropathy (DN), and mast cells (MCs) appear to increase in number within the kidney of humans and animals with diabetes. Disodium cromoglycate (CG) not only inhibits the degranulation of MCs but also has several secondary effects that may improve inflammation. However, little is known about the effects of CG treatment on kidney collagen deposition and myofibroblast population in animals with type I diabetes (DM1). Data presented here suggest that the increases in the density and activity of MCs within the kidney in the early stages of DN contribute to tubulointerstitial collagen deposition, even in the absence of alterations in the renal myofibroblast population. Moreover, CG treatment showed renoprotective effects in rats with DM1, which appear to be linked to its mast cell stabilizing property and its ability to avoid some detrimental morphofunctional alterations.

Additive cell protective and oxidative stress reducing effects of combined treatment with cromolyn sodium and masitinib on MPTP-induced toxicity in SH-SY5Y neuroblastoma cells.

The suppression of oxidative-stress induced neurotoxicity by antioxidants serves as a potential preventive strategy for neurodegenerative diseases. In this study, we aimed to investigate the cell protective and antioxidant effects of masitinib and cromolyn sodium against toxin-induced neurodegeneration. First, human neuroblastoma SH-SY5Y cells were differentiated into neuron-like (d)-SH-SY5Y cells. The differentiated cells were confirmed by immuno-staining with anti-PGP9.5 antibody, a neuronal marker. Cell culture groups were formed, and a neurotoxin, 1-methyl-4-phenyl1,2,3,6-tetrahydropyridine (MPTP) was applied on cells followed by masitinib and/or cromolyn sodium treatments. Survival rate of cells were detected by MTT assay. Anti-inflammatory Transforming Growth Factor-ß1 (TGF-ß1) and nitric oxide (NO) levels and total oxidant and antioxidant capacities (TOC and TAC) in cell conditioned media (CM) were measured. Morphological analysis and apoptotic nuclear assessment of cells were also noted. When (d)-SH-SY5Y cells were exposed to neurotoxin, cell viability rates of these cells were found to be decreased in a concentration-dependent manner. CM of toxin applied group displayed higher levels of TOC/TAC ratios and NO levels compared to control (p < 0.01). Both masitinib and cromolyn sodium protected cells from toxin-induced cell death as revealed by ameliorated rates of viability, reversed toxin-induced elevation of TOC/TAC ratios, and decreased NO levels in their CM (p < 0.01). Combined treatment significantly reduced TOC/TAC ratios and NO levels more effectively compared to mono-treatments. Both drugs also increased TGF-ß1 levels significantly in cell CM. When these agents were tested for therapeutic effects against toxin-induced cell degeneration, better viability results were obtained by both masitinib and cromolyn sodium treatment, with significantly better amelioration provided by combined application of these drugs (p < 0.01). This study demonstrated new findings that combined treatment with cromolyn sodium, an FDA-approved drug of asthma, and masitinib, an orally administered drug with a low toxicity, exert neuroprotective and additive therapeutic effects. We propose that combination therapy of masitinib and cromolyn sodium may represent an innovative treatment in neurodegenerative diseases. Combination therapy may be more advantageous that it enables combined application of lower doses of both drugs, providing less side effects.

A pharmacological approach assessing the role of mast cells in insulin infusion site inflammation.

Background Extending the lifespan of subcutaneous insulin administration sets and infusion pumps requires overcoming unreliable insulin delivery induced by dermal reactions. All commercially available insulin formulations contain insulin phenolic preservatives (IPP), which stabilize the insulin molecule but result in unwanted cell and tissue toxicity. Mast cells, which are the first line of defense once the epithelium is breached, are particularly abundant beneath the skin surface. Thus, we hypothesize a sequence of events initiated by device insertion that activates skin mast cells (MC) that subsequently trigger neutrophil and monocyte/macrophage recruitment. The ensuing inflammatory response compromises effective insulin infusion therapy. Methods We employed a non-genetic, pharmacological approach to MC membrane stabilization using Cromolyn sodium (CS), which inhibits MC degranulation. These studies were conducted in our modified air pouch mouse model using non-diabetic and streptozotocin induced diabetic mice. We evaluated the impact of systemic CS through intraperitoneal injections, as well as the impact of local CS through co-infusion, on infusion catheter insertion and IPP-induced inflammation. Results CS at a concentration of 50 mg/kg minimized inflammation triggered in response to insulin phenolic preservatives present in standard insulin formulations. The resultant degree of tissue inflammation was comparable to that observed with saline injections. Conclusion Targeting MC has the potential to extend the longevity of insulin infusion sets by mitigating the inflammatory response. Future studies should be directed at employing other MC models, such as newer Cre/loxP mouse strains, to confirm the sentinel role of MC in insulin infusion therapy.

Cromolyn platform suppresses fibrosis and inflammation, promotes microglial phagocytosis and neurite outgrowth.

Neurodegenerative diseases are characterized by chronic neuroinflammation and may perpetuate ongoing fibrotic reactions within the central nervous system. Unfortunately, there is no therapeutic available that treats neurodegenerative inflammation and its sequelae. Here we utilize cromolyn, a mast cell inhibitor with anti-inflammatory capabilities, and its fluorinated analogue F-cromolyn to study fibrosis-related protein regulation and secretion downstream of neuroinflammation and their ability to promote microglial phagocytosis and neurite outgrowth. In this report, RNA-seq analysis shows that administration of the pro-inflammatory cytokine TNF-α to HMC3 human microglia results in a robust upregulation of fibrosis-associated genes. Subsequent treatment with cromolyn and F-cromolyn resulted in reduced secretion of collagen XVIII, fibronectin, and tenascin-c. Additionally, we show that cromolyn and F-cromolyn reduce pro-inflammatory proteins PLP1, PELP1, HSP90, IL-2, GRO-α, Eotaxin, and VEGF-Α, while promoting secretion of anti-inflammatory IL-4 in HMC3 microglia. Furthermore, cromolyn and F-cromolyn augment neurite outgrowth in PC12 neuronal cells in concert with nerve growth factor. Treatment also differentially altered secretion of neurogenesis-related proteins TTL, PROX1, Rab35, and CSDE1 in HMC3 microglia. Finally, iPSC-derived human microglia more readily phagocytose Aß42 with cromolyn and F-cromolyn relative to controls. We propose the cromolyn platform targets multiple proteins upstream of PI3K/Akt/mTOR, NF-κB, and GSK-3ß signaling pathways to affect cytokine, chemokine, and fibrosis-related protein expression.

From Combinations to Single-Molecule Polypharmacology-Cromolyn-Ibuprofen Conjugates for Alzheimer's Disease.

Despite Alzheimer's disease (AD) incidence being projected to increase worldwide, the drugs currently on the market can only mitigate symptoms. Considering the failures of the classical paradigm "one target-one drug-one disease" in delivering effective medications for AD, polypharmacology appears to be a most viable therapeutic strategy. Polypharmacology can involve combinations of multiple drugs and/or single chemical entities modulating multiple targets. Taking inspiration from an ongoing clinical trial, this work aims to convert a promising cromolyn-ibuprofen drug combination into single-molecule "codrugs." Such codrugs should be able to similarly modulate neuroinflammatory and amyloid pathways, while showing peculiar pros and cons. By exploiting a linking strategy, we designed and synthesized a small set of cromolyn-ibuprofen conjugates (4-6). Preliminary plasma stability and neurotoxicity assays allowed us to select diamide 5 and ethanolamide 6 as promising compounds for further studies. We investigated their immunomodulatory profile in immortalized microglia cells, in vitro anti-aggregating activity towards Aß42-amyloid self-aggregation, and their cellular neuroprotective effect against Aß42-induced neurotoxicity. The fact that 6 effectively reduced Aß-induced neuronal death, prompted its investigation into an in vivo model. Notably, 6 was demonstrated to significantly increase the longevity of Aß42-expressing Drosophila and to improve fly locomotor performance.

Evaluation of Fluorinated Cromolyn Derivatives as Potential Therapeutics for Alzheimer's Disease.

BACKGROUND: Cromolyn is an anti-neuroinflammatory modulator with a multifactorial mechanism of action that has been shown to inhibit amyloid-ß (Aß) aggregation and enhance microglial uptake and clearance of Aß. OBJECTIVE: We report the effects of fluoro-cromolyn derivatives on microglial cell toxicity and microglial clearance of Aß42. METHODS: Microglial cell toxicity for cromolyn derivatives were determined in naive BV2 microglial cells. Microglial clearance assays were performed with Aß42 in naive BV2 microglial cell line and single cell clone BV2 line expressing CD33WT. PET imaging was performed for three F-18 analogs in a rhesus macaque. RESULTS: All compounds but derivative 8 exhibited low microglial cell toxicity. Cromolyn 1 and derivatives 2, 4, and 7 displayed an increased uptake on Aß42 in naïve BV2 microglial cells. Derivative 4 increased Aß42 uptake in a dose-dependent manner and at 75µM resulted in a one-fold increase in Aß42 uptake in BV2-CD33WT. PET imaging for three [18F]cromolyn analogs revealed the order of brain tracer penetration to be 4a > 10 > 2a. Tracer 4a exhibited enhanced uptake in areas of high perfusion (putamen, grey matter, and cerebellum) and lower signal in areas of lower perfusion (caudate, thalamus, and white matter). CONCLUSION: Substantial uptake of Aß42 in both naïve BV2 and BV2-CD33WT cells observed with 4 indicate conversion of microglial cells from a pro-inflammatory to an activation state favoring Aß phagocytosis/clearance. These findings suggest that a fluoro-cromolyn analog could reduce fibril-prone Aß42in vivo and thereby serve as a therapeutic for the treatment and prevention of AD.