Shen-Shih Chiang

Immunomodulatory and antioxidant potential of Lactobacillus exopolysaccharides

BACKGROUND Immunomodulation by probiotic microorganisms has become a topic of increasing interest in food microbiology. Polysaccharides are broadly used in the food industry as gelling, thickening, stabilizing, or emulsifying agents. Some probiotics such as lactic acid bacteria also produce exopolysaccharides that stimulate macrophage production of cytokines. The aim of this study was to characterize the effects of exopolysaccharides of Lactobacillus paracasei subsp. paracasei NTU 101 (101EP) and Lactobacillus plantarum NTU 102 (102EP) exopolysaccharides on antioxidant activity and immunomodulation in vitro. RESULTS The sugar composition (including arabinose, galactose, glucose, fructose, mannose, and maltose) of 101EP and 102EP was quantified by high-performance anion-exchange chromatography. Cytokine production (including IL-6, TNF-α, and IL-1β) was induced by 101EP and 102EP in Raw 264.7 in a dose-dependent manner (5-500 µg mL(-1) ). 101EP and 102EP also demonstrated potential antioxidant properties (1,1-diphenyl-2-picrylhydrazyl radical scavenging activity, chelation of ferrous ions, inhibition of linoleic acid peroxidation, and reducing power) in vitro. CONCLUSION 101EP and 102EP stimulate cell proliferation and may be useful as a mild immune modulator of macrophages.

Beneficial effects of Lactobacillus paracasei subsp. paracasei NTU 101 and its fermented products

It is well-known that probiotics have a number of beneficial health effects in humans and animals, including the reduction of symptoms in lactose intolerance and enhancement of the bioavailability of nutrients. Probiotics have showed to possess antimutagenic, anticarcinogenic and hypocholesterolemic properties. Further, they were also observed to have antagonistic actions against intestinal and food-borne pathogens, to decrease the prevalence of allergies in susceptible individuals and to have immunomodulatory effects. Typically, the bacteria colonise the intestinal tract first and then reinforce the host defence systems by inducing a generalised mucosal immune response, balanced T-helper cell response, self-limited inflammatory response and secretion of polymeric IgA. Scientific reports showed that the Taiwan native lactic acid bacterium from newborn infant faeces identified as Lactobacillus paracasei subsp. paracasei NTU 101 and its fermented products proved to be effective for the management of blood cholesterol and pressure, prevention of gastric mucosal lesion development, immunomodulation and alleviation of allergies, anti-osteoporosis and inhibition the fat tissue accumulation. This review article describes that the beneficial effects of this Lactobacillus strains and derivative products may be suitable for human and animals.

Antiosteoporotic effects of Lactobacillus -fermented soy skim milk on bone mineral density and the microstructure of femoral bone in ovariectomized mice.

Osteoporosis is a major skeletal disease associated with loss of estrogen in postmenopausal women. In this study, Lactobacillus paracasei subsp. paracasei NTU 101 (NTU 101F) and Lactobacillus plantarum NTU 102 (NTU 102F) were used as starters to ferment soy skim milk. This was then used as a nutritional supplement for 8 weeks to ovariectomized (OVX) mice. This study reveals that soy skim milk fermented with lactobacilli can increase the contents of aglycone isoflavones, soluble calcium, and vitamin D(3). The trabecular bone volumes and trabecular number of the distal femur in mice fed NTU 101F increased by a factor of 1.48 and 1.74 compared with the OVX group. The bone network density and thickness of the distal metaphyseal trabecular in mice fed NTU 101F and Fosamax was significantly greater than that of OVX mice. These results suggest that fermented soy skim milk can attenuate bone loss in OVX mice and lower the risk of osteoporosis.

Beneficial preventive effects of gastric mucosal lesion for soy-skim milk fermented by lactic acid bacteria.

In this study, Lactobacillus paracasei subsp. paracasei NTU101 and Lactobacillus plantarum NTU 102 were used as starter to ferment soy-skim milk, and the optimal mixing ratio was evaluated. The influence of lactic acid bacteria (LAB)-fermented soy-skim milk on mucosal integrity in a gastric mucosal lesion rat model was also investigated. After 24 h, cell densities of L. paracasei subsp. paracasei NTU 101 and L. plantarum NTU 102 fermented in 75% soy milk and 25% milk (optimal condition) were 1.2 × 10(9) and 2.5 × 10(9) CFU/mL. After 180 days at 4 °C, the cell densities of the freeze-dried powders of the fermented soy-skim milks were 1 × 10(9) CFU/g; slight variations in pH and acidity were observed. Pylorus ligation with acidified ethanol treatment was used as the gastric lesion animal model. LAB-fermented soy-skim milk reduced the gastric lesion index and the lipid peroxides (LPO) of gastric mucosa and serum. Administration of the fermented soy-skim milk enhanced superoxide dismutase (SOD) activity and prostaglandin E(2) (PGE(2)) synthesis. Therefore, LAB-fermented soy-skim milk at 10(9) CFU/day protects against gastric injury.

Beneficial effects of phytoestrogens and their metabolites produced by intestinal microflora on bone health.

Phytoestrogens are a class of bioactive compounds derived from plants and exert various estrogenic and antiestrogenic effects. Estrogen deficiency osteoporosis has become a serious problem in elderly women. The use of ovariectomized (OVX) rat or mice models to simulate the postmenopausal condition is well established. This review aimed to clarify the sources, biochemistry, absorption, metabolism, and mode of action of phytoestrogens on bone health in intervention studies. In vitro, phytoestrogens promote protein synthesis, osteoprotegerin/receptor activation of nuclear factor-kappa B ligand ratio, and mineralization by osteoblast-like cells (MC3T3-E1). In the OVX murine model, administration of phytoestrogens can inhibit differentiation and activation of osteoclasts, expression of tartrate-resistant acid phosphatase, and secretion of pyridinoline compound. Phytoestrogens also enhance bone formation and increase bone mineral density and levels of alkaline phosphatase, osteocalcin, osteopontin, and α1(I) collagen. Results of mechanistic studies have indicated that phytoestrogens suppress the rate of bone resorption and enhance the rate of bone formation.

Osteoprotective Effect of Monascus-fermented Dioscorea in Ovariectomized Rat Model of Postmenopausal Osteoporosis

This experiment established the ovariectomized (OVX) rat model of postmenopausal osteoporosis and examined the effect of the oral administration of different dosages of dioscorea, red mold dioscorea (RMD), and soy isoflavones on bone mineral density (BMD). Three months after osteoporosis had been induced and 4 weeks after feeding had begun, the tibia and femur BMD of OVX rats administered RMD showed significant increases compared with that of all other groups of OVX rats. Closer examination using microcomputed tomography also revealed that the RMD-administered rats had denser trabecular bone volume and a higher trabecular number compared to all other rat groups. Reconstructed 3D imaging indicated increases in cancellous bone mineral content, cancellous bone mineral density, and cortical bone mineral content of the proximal tibia in OVX rats. These findings indicate that administration of monacolin K and phytoestrogen diosgenin could prevent bone loss induced by estrogen deficiency.

Antcin C from Antrodia cinnamomea Protects Liver Cells Against Free Radical-Induced Oxidative Stress and Apoptosis In Vitro and In Vivo through Nrf2-Dependent Mechanism

In this study, we investigated the cytoprotective effects of antcin C, a steroid-like compound isolated from Antrodia cinnamaomea against AAPH-induced oxidative stress and apoptosis in human hepatic HepG2 cells. Pretreatment with antcin C significantly protects hepatic cells from AAPH-induced cell death through the inhibition of ROS generation. Furthermore, AAPH-induced lipid peroxidation, ALT/AST secretion and GSH depletion was significantly inhibited by antcin C. The antioxidant potential of antcin C was correlated with induction of antioxidant genes including, HO-1, NQO-1, γ-GCLC, and SOD via transcriptional activation of Nrf2. The Nrf2 activation by antcin C is mediated by JNK1/2 and PI3K activation, whereas pharmacologic inhibition of JNK1/2 and PI3K abolished antcin C-induced Nrf2 activity. In addition, AAPH-induced apoptosis was significantly inhibited by antcin C through the down-regulation of pro-apoptotic factors including, Bax, cytochrome c, capase 9, -4, -12, -3, and PARP. In vivo studies also show that antcin C significantly protected mice liver from AAPH-induced hepatic injury as evidenced by reduction in hepatic enzymes in circulation. Further, immunocytochemistry analyses showed that antcin C significantly increased HO-1 and Nrf2 expression in mice liver tissues. These results strongly suggest that antcin C could protect liver cells from oxidative stress and cell death via Nrf2/ARE activation.

Effect of bioactive compounds in lactobacilli-fermented soy skim milk on femoral bone microstructure of aging mice

BACKGROUND Soy skim milks fermented with lactobacilli contain various phytochemicals such as isoflavones and peptides. We used lactobacilli-fermented soy skim milk as a nutritional supplement for 6 weeks to investigate its anti-osteoporosis effect in 13-month-old female BALB/c aging mice. Freeze-dried powder of soy skim milk fermented by Lactobacillus paracasei subsp. paracasei NTU 101 (NTU 101F) and L. plantarum NTU 102 (NTU 102F) were used in this study. RESULTS The trabecular bone volumes in mice fed NTU 101F and NTU 102F increased by a factor of 3.48 and 2.16 compared with control values, respectively. The network density and thickness of distal metaphyseal trabecular bone in mice fed with NTU 101F and NTU 102F milks were significantly denser than that of control mice; moreover, the NTU 101F group had the largest resting area ratio and smallest resorbing area compared with other groups. The beneficial effect may due to isoflavones as well as higher amounts of polysaccharide and peptide in NTU 101F milk. CONCLUSION The results suggest that dietary supplement with fermented soy skim milk can attenuate aging-induced bone loss in BALB/c mice and possibly lower the risk of osteopenia or osteoporosis in aging.

Immunomodulatory effects of dead Lactobacillus on murine splenocytes and macrophages

Abstract To elucidate the immunomodulation effects of dead lactobacilli, whole cells and gastrointestinal enzymatic hydrolysates of supernatants and precipitates from Lactobacillus paracasei subsp. paracasei NTU 101 and L. plantarum NTU 102 on RAW264.7 macrophages and splenocytes were investigated. Increased NO, COX-2 expression, IL-10 and IL-12 were observed in high-dose precipitates and whole cells of both strains after 24-h stimulation. All of the hydrolysates and whole cells from both strains induced lower pro-inflammatory cytokines (IL-1β and IL-6) than LPS. The supernatants activated cell division to the S phase or promoted advance to the G2/M phase. Regardless of the Lactobacillus strains, higher levels of TNF-α, IL-6, IL-10 and IL-12 in splenocytes were induced by the precipitates. Supernatant of NTU 101 increased the amounts of IFN-γ than precipitate in splenocytes. It shows that hydrolysates of NTU 101 induce the proliferations of macrophage and splenocyte and the release of IL-10 and IL-12 cytokines to modulate the innate and adaptive immune systems and inflammatory response.

Immunomodulatory activities and antioxidant properties of polysaccharides from Monascus-fermented products in vitro.

BACKGROUND Monascus-fermented products have featured in Chinese cuisine for thousands of years and are widely used as food colourants and dietary materials in many Asian countries. Rice and dioscorea fermented with Monascus purpureus NTU 568 have health-promoting attributes in vitro and in vivo. The aim of this study was to investigate the immunomodulatory and antioxidant effects of polysaccharides from red mould rice (RMRP) and red mould dioscorea (RMDP) in Raw 264.7 cells. RESULTS The results showed the antioxidant capabilities (including scavenging, chelating, inhibition of lipid peroxidation, and reducing power) of RMRP and RMDP at a concentration of 10 mg mL(-1). RMRP and RMDP also stimulated cell proliferation, nitric oxide production, phagocytosis and cytokine production (including IL1-β, IL-6 and TNF-α) in Raw 264.7 cells. CONCLUSION These findings demonstrate that RMRP and RMDP have antioxidant and immunomodulation potential to be developed as novel dietary supplements.