Methylsulfonylmethane modulates apoptosis of LPS/IFN-γ-activated RAW 264.7 macrophage-like cells by targeting p53, Bax, Bcl-2, cytochrome c and PARP proteins

A critical factor in reactive oxygen species (ROS) studies: the need to understand the chemistry of the solvent used: the case of DMSO

Reactive oxygen species (ROS) play critical roles in normal physiological processes including cellular signaling and immune responses. Various pathological conditions including infections of various types, inflammation, cancer, and respiratory conditions are associated with elevated levels of ROS. Therefore, there is widespread interest in understanding ROS concentrations under various pathophysiological conditions for diagnostic and therapeutic applications including ROS-triggered drug delivery. However, in determining ROS concentration, there are major concerns of inappropriate use of various methods that lead to erroneous results; this has prompted the publication of a consensus paper in Nature Metabolism by a group of ROS experts stating "Unfortunately, the application and interpretation of these measurements are fraught with challenges and limitations. This can lead to misleading claims." Along this line, we have identified an overlooked factor, which can significantly skew the results and results interpretation: the organic co-solvent. DMSO is one of the most widely used organic co-solvents to dissolve a reagent for bioassays. Herein, we describe the rapid oxidation of DMSO by hypochlorite and how this oxidation impacts results of ROS determination in buffer, cell culture media, cell culture, and cell lysates. We hope to use this one example to draw attention to the convoluted roles that DMSO and possibly other organic co-solvents can play and skew experimental results. We also hope to stimulate additional studies to bring more rigor to studying ROS concentration and biology.

Erythropoietin suppresses osteoblast apoptosis and ameliorates steroid-induced necrosis of the femoral head in rats by inhibition of STAT1-caspase 3 signaling pathway

BACKGROUND

Steroid-induced avascular necrosis of the femoral head (SANFH) is characterized by osteoblast apoptosis, leading to a loss of bone structure and impaired hip joint function. It has been demonstrated that erythropoietin (EPO) performs a number of biological roles.

OBJECTIVE

We examined the effects of EPO on SANFH and its regulation of the STAT1-caspase 3 signaling pathway.

METHOD

In vitro, osteoblasts were treated with dexamethasone (Dex) or EPO. We identified the cytotoxicity of EPO by CCK-8, the protein expression of P-STAT1, cleaved-caspase9, cleaved-caspase3, Bcl-2, BAX, and cytochrome c by Western blotting, and evaluated the apoptosis of osteoblasts by flow cytometry. In vivo, we analyzed the protective effect of EPO against SANFH by hematoxylin and eosin (H&E), Immunohistochemical staining, and Micro-computed tomography (CT).

RESULTS

In vitro, EPO had no apparent toxic effect on osteoblasts. In Dex-stimulated cells, EPO therapy lowered the protein expression of BAX, cytochrome c, p-STAT1, cleaved-caspase9, and cleaved-caspase3 while increasing the expression of Bcl-2. EPO can alleviate the apoptosis induced by Dex. In vivo, EPO can lower the percentage of empty bone lacunae in SANFH rats.

CONCLUSION

The present study shows that EPO conferred beneficial effects in rats with SANFH by inhibiting STAT1-caspase 3 signaling, suggesting that EPO may be developed as a treatment for SANFH.

The mechanism of chronic intracellular infection with Brucella spp

Globally, brucellosis is a widespread zoonotic disease. It is prevalent in more than 170 countries and regions. It mostly damages an animal's reproductive system and causes extreme economic losses to the animal husbandry industry. Once inside cells, Brucella resides in a vacuole, designated the BCV, which interacts with components of the endocytic and secretory pathways to ensure bacterial survival. Numerous studies conducted recently have revealed that Brucella's ability to cause a chronic infection depends on how it interacts with the host. This paper describes the immune system, apoptosis, and metabolic control of host cells as part of the mechanism of Brucella survival in host cells. Brucella contributes to both the body's non-specific and specific immunity during chronic infection, and it can aid in its survival by causing the body's immune system to become suppressed. In addition, Brucella regulates apoptosis to avoid being detected by the host immune system. The BvrR/BvrS, VjbR, BlxR, and BPE123 proteins enable Brucella to fine-tune its metabolism while also ensuring its survival and replication and improving its ability to adapt to the intracellular environment.

Incorporation of Dietary Methyl Sulfonyl Methane into the Egg Albumens of Laying Hens

This study evaluated the effects of graded levels of dietary methyl sulfonyl methane (MSM) on the laying performance, egg quality, antioxidant capacity, and the incorporation of MSM into the egg albumen of laying hens. A total of 240 73-week-old laying hens (Lohmann Brown Lite) were randomly allotted to 1 of 5 dietary treatments, with 8 replicates of 6 birds per replicate. The experimental diets were formulated by mixing corn and soybean meal-based diets with MSM to reach 0.0, 1.0, 2.0, 3.0, and 4.0 g per kg of diet, and were fed to the birds for 12 weeks. Increasing dietary MSM led to a significant quadratic effect on the feed intake and feed conversion ratio at 4 weeks (p < 0.05). However, none of the egg qualities and egg components were altered by dietary MSM. The deposition of MSM in egg albumens increased in a linear manner (p < 0.05) in response to the increasing dietary MSM levels. The concentration of malondialdehyde in the egg yolk decreased at 12 weeks (linear and quadratic effect; p < 0.05), as the dietary MSM levels increased. Increasing dietary MSM affected the indicators of antioxidant/oxidative stress in the serum samples, such as superoxide dismutase at 12 weeks (linear and quadratic effect; p < 0.05), total antioxidant capacity at 8 and 12 weeks (linear effect; p < 0.05), and malondialdehyde at 8 weeks (linear effect; p < 0.05). Taken together, our study shows that dietary MSM has potential to be used as an antioxidant feed additive for laying hens, and can be used to produce functional eggs with health benefits for humans.

Mitochondrial metabolism regulates macrophage biology

Mitochondria are critical for regulation of the activation, differentiation, and survival of macrophages and other immune cells. In response to various extracellular signals, such as microbial or viral infection, changes to mitochondrial metabolism and physiology could underlie the corresponding state of macrophage activation. These changes include alterations of oxidative metabolism, mitochondrial membrane potential, and tricarboxylic acid (TCA) cycling, as well as the release of mitochondrial reactive oxygen species (mtROS) and mitochondrial DNA (mtDNA) and transformation of the mitochondrial ultrastructure. Here, we provide an updated review of how changes in mitochondrial metabolism and various metabolites such as fumarate, succinate, and itaconate coordinate to guide macrophage activation to distinct cellular states, thus clarifying the vital link between mitochondria metabolism and immunity. We also discuss how in disease settings, mitochondrial dysfunction and oxidative stress contribute to dysregulation of the inflammatory response. Therefore, mitochondria are a vital source of dynamic signals that regulate macrophage biology to fine-tune immune responses.

LncRNA ZFAS1 plays a role in regulating the inflammatory responses in sepsis-induced acute lung injury via mediating miR-193a-3p

OBJECTIVE

To explore the role of lncRNA ZFAS1-mediated miR-193a-3p in the regulation of inflammatory responses in rats with sepsis-induced acute lung injury (ALI).

METHODS

Sepsis-induced ALI models were constructed by LPS induction and then injected with ZFAS1 overexpression plasmid. Thereafter, lung injury score and the W/D weight ratio were calculated. Besides, bronchoalveolar lavage fluid (BALF) was isolated from rats to perform the cell count and protein quantification, while qRT-PCR and ELISA were performed to detect the inflammatory cytokines expressions. In vitro, NR8383 cells were transfected and then treated with LPS, followed by the measurement of inflammatory cytokines, cell viability and cell apoptosis.

RESULTS

In comparison with the Control group, rats in the LPS group presented sharp increases in the W/D weight ratio and injury score of lung, total protein concentration and the count of neutrophils and macrophages in BALF. Besides, rats in LPS group also resulted in a decrease in ZFAS1 expression and increase in miR-193a-3p expression in lung tissues, with the increased pro-inflammatory cytokines. Dual luciferase reporter gene assay confirmed a target relation between miR-193a-3p and ZFAS1. As compared to the Blank group, NR8383 cells in the LPS group had up-regulated pro-inflammatory cytokines with declined cell viability and elevated cell apoptosis; and meanwhile, ZFAS1 and Bcl-2 were decreased but miR-193a-3p and Bax were increased. Overexpression of ZFAS1 could significantly improve LPS-induced ALI in vivo and in vitro with reduced levels of pro-inflammatory cytokines.

CONCLUSION

Overexpression of ZFAS1, possibly via targeting the expression of miR-193a-3p, could inhibit the apoptosis and ameliorate the inflammatory responses of ALI in sepsis.

lncRNA RMRP Prevents Mitochondrial Dysfunction and Cardiomyocyte Apoptosis via the miR-1-5p/hsp70 Axis in LPS-Induced Sepsis Mice

Both long non-coding RNA (lncRNA) RMRP and heat shock protein (HSP) 70 have been known to play crucial roles in inflammation. The present study investigated the roles of lncRNA RMRP and HSP70 protein 4 (HSPA4) in lipopolysaccharide (LPS)-induced sepsis. The C57BL/6 mice were treated with LPS, following which the cardiomyocytes were isolated for in vitro experiments. Further, a cardiac muscle cell line, HL-1 was transfected with plasmids expressing RMRP and HSPA4, si-NC, si-HSPA4, miR-1-5p mimic, and controls in vitro. Cell apoptosis, mitochondrial membrane potential (MMP), and levels of intracellular reactive oxygen species (ROS), mRNAs, and proteins were detected in the transfected mice tissues and cells. The LPS treatment significantly reduced the expression levels of RMRP, MMP, and mitochondrial cytochrome C. Moreover, it enhanced the cardiomyocyte apoptosis, intracellular ROS levels, cytoplasm cytochrome C levels, and the expression of caspase-3 and caspase-9 and nuclear factor κB (NF-κB) p65 subunit. The predicted RMRP-miR-1-5p-HSPA4 network was validated by co-transfection experiments in vitro in HL-1 cells. The transfection of miR-1-5p-treated cells with pcDNA-RMRP enhanced the levels of the protein HSPA4; however, no change at the mRNA level was observed. Moreover, miR-1-5p mimic attenuated the protective effect of pcDNA-HSPA4 against LPS-induced mitochondrial damage and apoptosis. In addition, we observed that silencing of HSPA4 increased the expression of nuclear p65; however, this effect could be reversed by co-transfection with pcDNA-RMRP. The lncRNA RMRP axis acts as a sponge for miR-1-5p. RMRP inhibits LPS-induced apoptosis of cardiomyocytes and mitochondrial damage by suppressing the post-transcriptional regulatory function of miR-1-5p on HSPA4. We believe that RMRP exhibits therapeutic potential for LPS-induced myocardial dysfunction both in vitro and in vivo.

Conjugation with Methylsulfonylmethane Improves Hyaluronic Acid Anti-Inflammatory Activity in a Hydrogen Peroxide-Exposed Tenocyte Culture In Vitro Model

Rotator cuff tears (RCTs) and rotator cuff disease (RCD) are important causes of disability in middle-aged individuals affected by nontraumatic shoulder dysfunctions. Our previous studies have demonstrated that four different hyaluronic acid preparations (HAPs), including Artrosulfur^® hyaluronic acid (HA) (Alfakjn S.r.l., Garlasco, Italy), may exert a protective effect in human RCT-derived tendon cells undergoing oxidative stress damage. Recently, methylsulfonylmethane (MSM) (Barentz, Paderno Dugnano, Italy) has proven to have anti-inflammatory properties and to cause pain relief in patients affected by tendinopathies. This study aims at evaluating three preparations (Artrosulfur^® HA, MSM, and Artrosulfur^® MSM + HA) in the recovery from hydrogen peroxide-induced oxidative stress damage in human tenocyte. Cell proliferation, Lactate Dehydrogenase (LDH) release, and inducible nitric oxide synthases (iNOS) and prostaglandin E2 (PGE2) modulation were investigated. In parallel, expression of metalloproteinases 2 (MMP2) and 14 (MMP14) and collagen types I and III were also examined. Results demonstrate that Artrosulfur^® MSM + HA improves cell escape from oxidative stress by decreasing cytotoxicity and by reducing iNOS and PGE2 secretion. Furthermore, it differentially modulates MMP2 and MMP14 levels and enhances collagen III expression after 24 h, proteins globally related to rapid acceleration of the extracellular matrix (ECM) remodelling and thus tendon healing. By improving the anti-cytotoxic effect of HA, the supplementation of MSM may represent a feasible strategy to ameliorate cuff tendinopathies.

Lysergic acid diethylamide causes mouse retinal damage by up-regulating p-JAK1/p-STAT1

Purpose: Lysergic acid diethylamide (LSD) is a powerful hallucinogen with high potential for abuse. There is far less known about its effects on the retina, especially the underlying mechanisms. This study was to investigate the acute toxicity of LSD on the retina of C57 mice and its mechanisms of action.Methods: C57 mice were treated with LSD at progressively increasing doses (0.2-1.2 mg/kg) intraperitoneally two times daily for 5 days, mice treated with saline served as negative control. Electroretinography (ERG) was used to test the function of the retina. Toluidine blue staining was used to detect the morphology of the retina. Enzyme-linked immunosorbent assay (ELISA) was used to measure the apoptosis-related factors. Real-time PCR and western blot techniques were used to measure expression changes of genes and proteins, respectively.Results: LSD treatment caused retinal damage, as shown by a decrease in ERG response and the loss of photoreceptor cells. LSD treatment also increased apoptosis through up-regulating the expression of p-JAK1/p-STAT1.Conclusions: Our study indicated that intraperitoneal administration of LSD-induced retinal damage of C57 mice, at least partially through regulating the JAK/STAT pathway.

Methylsulfonylmethane and mobilee prevent negative effect of IL-1β in human chondrocyte cultures via NF-κB signaling pathway

Nutraceuticals are compounds that serve as nutrition with an easy accessibility and favourable safety profile. Recent studies showed their potential activity on osteoarthritis (OA) inflammation and cartilage metabolism. We investigated the effect of methylsulfonylmethane (MSM) and mobilee in human OA chondrocyte cultures exposed to interleukin (IL)-1β. OA cartilage was obtained from femoral heads of five patients undergoing total replacement surgery. Chondrocytes were incubated with mobilee (200 and 500 μM) and MSM (2000 and 6000 μM) in presence of IL-1β (10 ng/mL) and nuclear factor (NF)-κB inhibitor (BAY 11-7082, 1 μM), for 24 and 48 h. Viability and apoptosis were performed by MMT and flow cytometry. The metalloproteinase (MMP)-1,-3,-13 and type II collagen (Col2a1) were analyzed by qRT-PCR and ELISA, and NF-κB activation by immunofluorescence. IL-1β stimulus determined a significant regulation of survival, apoptotic ratio, as well as of gene expression and serum levels of MMP-1,-3,-13 and Col2a1 in OA chondrocytes compared to baseline. Mobilee and MSM incubation significantly reversed the effect of IL-1β. IL-1β significantly induced NF-κB p50 nuclear translocation, which was significantly counteracted by the pre-treatment of OA chodrocytes with the tested compounds. BAY11-7082 significantly modulated MMPs and Col2a1 expression respectively to basal state. Co-treatment of IL-1β with mobilee, MSM and BAY11-7082 didn't cause changes of MMPs or Col2a1 beyond that caused by each single treatment. We demonstrated that MSM and mobilee have a beneficial effect on OA chondrocytes metabolism, probably due to the modulation of NF-κB pathway, providing a powerful rationale for the use of these substances in OA treatment.

Protective effect of methylsulfonylmethane in caerulein-induced acute pancreatitis and associated lung injury in mice

Objectives

In the present study, we have elaborated the anti-inflammatory mechanism of MSM through homing of CD34+ stem cells towards an inflamed region by regulating hydrogen sulfide (H2S) in an in vivo model of caerulein-induced acute pancreatitis (AP) and associated lung injury.

Methods

Male Swiss mice were treated with hourly intraperitoneal injections of caerulein (50 μg/kg) for 6 h. MSM (500 mg/kg) was administered intraperitoneally 1 h after the first caerulein injection (therapeutic). The serum amylase activity and myeloperoxidase (MPO) activity in lung and pancreas were measured. The levels of H2S and interleukin (IL)-1β, cystathionine-γ-lyase (CSE) and CD34+ expressions in pancreas and lungs were determined by RT-PCR and ELISA.

Key Findings

Methylsulfonylmethane significantly ameliorated pancreas and lung histopathological changes, decreased serum amylase, MPO activity and inhibited caerulein-induced IL-1β expression. Furthermore, MSM reduced caerulein-induced H2S levels by alleviating the expression of CSE in pancreas and lungs and increased CD34 expression and inhibited nuclear factor (NF)-κB translocation in caerulein-induced AP and associated lung injury.

Conclusions

These findings indicate that MSM can effectively reduce inflammatory responses and induce the homing of CD34+ cells to the injured tissues.

Methylsulfonylmethane: Applications and Safety of a Novel Dietary Supplement

Methylsulfonylmethane (MSM) has become a popular dietary supplement used for a variety of purposes, including its most common use as an anti-inflammatory agent. It has been well-investigated in animal models, as well as in human clinical trials and experiments. A variety of health-specific outcome measures are improved with MSM supplementation, including inflammation, joint/muscle pain, oxidative stress, and antioxidant capacity. Initial evidence is available regarding the dose of MSM needed to provide benefit, although additional work is underway to determine the precise dose and time course of treatment needed to provide optimal benefits. As a Generally Recognized As Safe (GRAS) approved substance, MSM is well-tolerated by most individuals at dosages of up to four grams daily, with few known and mild side effects. This review provides an overview of MSM, with details regarding its common uses and applications as a dietary supplement, as well as its safety for consumption.

The α-cyclodextrin complex of the Moringa isothiocyanate suppresses lipopolysaccharide-induced inflammation in RAW 264.7 macrophage cells through Akt and p38 inhibition

In the last decades, a growing need to discover new compounds for the prevention and treatment of inflammatory diseases has led researchers to consider drugs derived from natural products as a valid option in the treatment of inflammation-associated disorders. The purpose of the present study was to investigate the anti-inflammatory effects of a new formulation of Moringa oleifera-derived 4-(α-L-rhamnopyranosyloxy)benzyl isothiocyanate as a complex with alpha-cyclodextrin (moringin + α-CD) on lipopolysaccharide (LPS)-stimulated RAW 264.7 macrophage cells, a common model used for inflammation studies. In buffered/aqueous solution, the moringin + α-CD complex has enhanced the water solubility and stability of this isothiocyanate by forming a stable inclusion system. Our results showed that moringin + α-CD inhibits the production of inflammatory mediators in LPS-stimulated macrophages by down-regulation of pro-inflammatory cytokines (TNF-α and IL-1β), by preventing IκB-α phosphorylation, translocation of the nuclear factor-κB (NF-κB), and also via the suppression of Akt and p38 phosphorylation. In addition, as a consequence of upstream inhibition of the inflammatory pathway following treatment with moringin + α-CD, the modulation of the oxidative stress (results focused on the expression of iNOS and nitrotyrosine) and apoptotic pathway (Bax and Bcl-2) was demonstrated. Therefore, moringin + α-CD appears to be a new relevant helpful tool to use in clinical practice for inflammation-associated disorders.

Knockdown of GATAD2A suppresses cell proliferation in thyroid cancer in vitro

GATAD2A (GATA zinc finger domain containing 2A), is a subunit of NuRP (nucleosome remodeling and histone deacetylation) which plays key roles in tumor growth inhibition and embryonic development. However, its role in thyroid cancer remains unclear. In our study, we established two thyroid cancer cell lines by lentivirus-delivered short hairpin (shRNA) to knockdown the expression of GATAD2A. Then loss-of-function assays indicated that knockdown of GATAD2A decreased the ability of cell proliferation and colony formation in thyroid cancer cells by MTT and colony formation assay, respectively. Moreover, cell cycle assay by flow cytometry revealed that the percentage of cells in G0/G1 phase was significantly decreased in GATAD2A knockdown cells accompanied by increase of cells in G2/M phase. Furthermore, inhibition of GATAD2A promoted cell apoptosis via elevating the expression of caspase-3 and PARP cleavage using Annexin V/7-AAD double staining and western blotting. In conclusion, GATAD2A is an essential factor in thyroid cancer cell growth and apoptosis, and may be a potential therapeutic biomarker in thyroid cancer.

Methylsulfonylmethane (MSM), an organosulfur compound, is effective against obesity-induced metabolic disorders in mice

Methylsulfonylmethane (MSM), an organosulfur compound, has been used as a dietary supplement that can improve various metabolic diseases. However, the effect of MSM on obesity-linked metabolic disorders remains unclear. The goal of the current study is to determine whether MSM has beneficial effects on glucose and lipid homeostasis in obesity-associated pathophysiologic states. High-fat diet-induced obese (DIO) and genetically obese diabetic db/db mice treated with MSM (1%-5% v/v, by drinking water) were studied. Metabolic parameters involved in glucose and lipid metabolism were determined. Treatment of DIO mice with MSM leads to a significant decrease in blood glucose levels. DIO mice treated with MSM are hypersensitive to insulin, as evidenced by decreased serum insulin and an increase in the area above the curve during an ITT. Concurrently, MSM reduces hepatic triglyceride and cholesterol contents in DIO mice. These effects are accompanied by reductions in gene expression of key molecules involved in lipogenesis and inflammation. FACS analysis reveals that MSM markedly increases the frequency of B cells and decreases the frequency of myeloid cells in peripheral blood and in bone marrow. Moreover, overnutrition-induced changes of femur microarchitecture are restored by MSM. In db/db mice, a marked impairment in glucose and lipid metabolic profiles is notably ameliorated when MSM is supplemented. These data suggest that MSM has beneficial effects on multiple metabolic dysfunctions, including hyperglycemia, hyperinsulinemia, insulin resistance, and inflammation. Thus, MSM could be the therapeutic option for the treatment of obesity-related metabolic disorders such as type 2 diabetes and fatty liver diseases.

Methylsulfonylmethane Induces p53 Independent Apoptosis in HCT-116 Colon Cancer Cells

Methylsulfonylmethane (MSM) is an organic sulfur-containing compound which has been used as a dietary supplement for osteoarthritis. MSM has been shown to reduce oxidative stress and inflammation, as well as exhibit apoptotic or anti-apoptotic effects depending on the cell type or activating stimuli. However, there are still a lot of unknowns about the mechanisms of actions of MSM. In this study, MSM was tested on colon cancer cells. 3-(4,5-Dimethylthiazol-2-yl)-2,5 diphenyltetrazolium bromide (MTT) assay and flow cytometric analysis revealed that MSM inhibited cell viability and increased apoptotic markers in both HCT-116 p53 +/+ and HCT-116 p53 −/− colon cancer cells. Increased poly (ADP-ribose) polymerase (PARP) fragmentation and caspase-3 activity by MSM also supported these findings. MSM also modulated the expression of various apoptosis-related genes and proteins. Moreover, MSM was found to increase c-Jun N-terminal kinases (JNK) phosphorylation in both cell lines, dose-dependently. In conclusion, our results show for the first time that MSM induces apoptosis in HCT-116 colon cancer cells regardless of their p53 status. Since p53 is defective in >50% of tumors, the ability of MSM to induce apoptosis independently of p53 may offer an advantage in anti-tumor therapy. Moreover, the remarkable effect of MSM on Bim, an apoptotic protein, also suggests its potential use as a novel chemotherapeutic agent for Bim-targeted anti-cancer therapies.