ABSTRACT
Carbon monoxide (CO) is generated by heme oxygenase (HO), and HO-1 is highly induced in monocytes and macrophages upon stimulation. Monocytes differentiate into macrophages, including pro-inflammatory (M1) and anti-inflammatory (M2) cells, in response to environmental signals. The present study investigated whether CO modulates macrophage differentiation and polarization, by applying the CO-releasing molecule-3 (CORM-3). Results showed that murine bone marrow cells are differentiated into macrophages by CORM-3 in the presence of macrophage colony-stimulating factor. CORM-3 increases expressions of macrophage markers, including F4/80 and CD11b, and alters the cell morphology into elongated spindle-shaped cells, which is a typical morphology of M2 cells. CORM-3 upregulates the expressions of genes and molecules involved in M2 polarization and M2 phenotype markers, such as STAT6, PPARγ, Ym1, Fizz1, arginase-1, and IL-10. However, exposure to CORM-3 inhibits the iNOS expression, suggesting that CO enhances macrophage differentiation and polarization toward M2. Increased HO-1 expression is observed in differentiated macrophages, and CORM-3 further increases this expression. Hemin, an HO-1 inducer, results in increased macrophage differentiation, whereas the HO-1 inhibitor zinc protoporphyrin IX inhibits differentiation. In addition, CORM-3 increases the proportion of macrophages in peritoneal exudate cells and enhances the expression of HO-1 and arginase-1 but inhibits iNOS. Taken together, these results suggest that the abundantly produced CO in activated macrophages enhances proliferation, differentiation, and polarization toward M2. It will probably help clear apoptotic cells, resolve inflammation, and promote wound healing and tissue remodeling.
Subject(s)
Arginase/genetics , Carbon Monoxide/metabolism , Cell Differentiation/genetics , Heme Oxygenase-1/genetics , Macrophages/drug effects , Animals , CD11b Antigen/genetics , Carbon Monoxide/adverse effects , Cell Polarity/drug effects , Gene Expression Regulation/drug effects , Humans , Macrophages/metabolism , Mice , Monocytes/drug effects , Nitric Oxide Synthase Type II/genetics , Organometallic Compounds/pharmacology , PPAR gamma/genetics , Phenotype , STAT6 Transcription Factor/geneticsABSTRACT
Postmenopausal osteoporosis is a common disorder resulting from increased osteoclastic activity. To determine the effect of Panax ginseng on postmenopausal osteoporosis, ovariectomized (OVX) mice were treated with 500 mg/kg/day P. ginseng extract (Pg) alone or in combination with hot water extract of Brassica oleracea (Bo) daily for 10 weeks, and the effect of the treatments on OVX-induced bone loss was examined. Bone weight, bone mineral density (BMD), osteoclast (OC) formation, OC marker expression, and biochemical parameters in blood were determined. OVX significantly increased body weight and decreased bone weight compared with those in the Sham group (p < 0.01). Pg or Bo alone did not affect OVX-induced bone loss, but a combination of Pg and Bo (Pg:Bo) recovered bone weight. The bones of OVX mice showed lower BMD than that of Sham mice, and the Pg:Bo = 3:1 restored the decreased BMD. Single treatment with Pg or Bo did not alter OC formation; however, the Pg:Bo = 3:1 inhibited OC formation. In addition, Pg and Bo lowered the OVX-induced elevation in blood glucose level. Thus, we suggest that Pg in combination with proper materials, such as Bo, might be a potential candidate treatment with minimal side effects protect against postmenopausal osteoporosis.
Subject(s)
Bone Density/drug effects , Brassica , Osteoporosis, Postmenopausal/prevention & control , Panax , Plant Extracts/administration & dosage , Animals , Disease Models, Animal , Drug Therapy, Combination , Female , Humans , Mice , Osteoclasts/drug effects , Osteoporosis, Postmenopausal/etiology , OvariectomyABSTRACT
Amino acids (AAs) are essential for protein synthesis, neurotransmission and macro molecule biosynthesis. Ala, Gln, Gly, Lys, Val and taurine (Tau) are the most abundant free AAs in mammals, and some of these react with hypochlorite (HOCl/OCl-) produced by myeloperoxidase in activated phagocytes to form N-chloroamino acids (NCAA). In this study, we reacted 20 AAs and Tau with sodium hypochlorite (NaOCl), then classified the products into five types (I-V) based on the change in their absorbance. Type I AAs (Ala, Arg, Gln, Gly, Ile, Lys, Phe, Ser, Tau, Thr and Val) generated a typical monochloramine peak at 252 nm, while Type II AAs (Asn and Tyr) and Type III AAs (Glu and Leu) produced peaks at 275 nm and 225 nm, respectively. The Type IV AAs (His, Met and Trp) did not show any distinct absorption peak, and Type V AAs (Asp, Cys and Pro) did not appear to react with NaOCl. The ArgCl and TauCl were stable, while GlnCl, GlyCl, IleCl, LysCl, PheCl and ValCl were less stable and AlaCl, SerCl and ThrCl were the least stable. Tau is the most abundant non-proteinogenic free AA in cellular fluid and has many physiological functions in the nervous, cardiovascular, renal and immune systems. Tau reacts with HOCl to form TauCl, which inhibits the production of proinflammatory mediators such as superoxide, nitric oxide (NO) and interleukins, while increasing the antioxidant proteins in macrophages. We determined the effects of Type I NCAA on cell viability, NO and TNF-α production in LPS-activated RAW 264.7 cells. All Type I NCAA showed dose-dependent cytotoxicity and inhibited LPS-induced NO production. However, only GlnCl, GlyCl, IleCl, LysCl, SerCl and TauCl inhibited LPS-induced TNF-α production. In summary, Type I NCAA showed dose-dependent cytotoxicity and inhibited NO production, while their effects on TNF-α varied. Our results suggest that Type I NCAA may serve as biological regulators similar to TauCl during inflammation.
