Explosively Puffed Ginseng Ameliorates Ionizing Radiation-Induced Injury of Colon by Decreasing Oxidative Stress-Related Apoptotic Cell Execution in Mice.

Although radiation therapy (RT) is a feasible treatment approach for early colorectal cancer, RT is considerably toxic to normal tissues due to the increased reactive oxygen species production, which can induce tissue damage. Ginseng, a natural antioxidant agent, exhibits the protective effects against ionizing radiation (IR)-induced damage in in vitro and in vivo models. The explosive puffing of ginseng has been investigated as a process to improve the efficacy of ginseng due to the resulting physicochemical changes in its functional components. In this study, we provided the evidence for promotion in the beneficial role of puffed ginseng extract (PGE) and associated mechanisms of action, in comparison with white ginseng extract (WGE), against IR-induced colorectal injury, using in vivo study on a mouse model. To study the role of PGE in preventing IR-induced damage, we examined colorectal injury and apoptotic changes in mice exposed to 137Cs at 8 Gy. High-performance liquid chromatography analysis showed that PGE had an increased total ginsenoside concentration with new generation of Rg3, Rg5, and Rk1, compared with the concentrations in WGE. Administering PGE, but not WGE, significantly ameliorated IR-induced colorectal cell death through negative regulation of apoptotic signaling pathways. These antiapoptotic effects of PGE were linked to the capacity to suppress the p53-mediated DNA damage response and NF-κB-mediated apoptotic signaling. Moreover, IR-induced oxidative stress in the colorectal epithelium was markedly reduced by PGE administration. Collectively, this study establishes a mechanism of action by which PGE counteracts IR-induced colorectal injury as a novel radioprotective agent.

The Edible Insect Gryllus bimaculatus Protects against Gut-Derived Inflammatory Responses and Liver Damage in Mice after Acute Alcohol Exposure.

Accumulation of reactive oxygen species (ROS) in response to excess alcohol exposure is a major cause of gut barrier disruption and lipopolysaccharide (LPS)-induced hepatic inflammation, as well as liver steatosis and apoptosis. This study was designed to investigate protective effects of the cricket Gryllus bimaculatus, an edible insect recognized by the Korea Food and Drug Administration, against acute alcoholic liver damage in mice. Administration of G. bimaculatus extracts (GBE) attenuated alcohol-induced steatosis and apoptotic responses in the liver and intestinal permeability to bacterial endotoxin. These protective effects were associated with suppression of ROS-mediated oxidative stress in both the liver and small intestine. Furthermore, in vivo and in vitro studies revealed that GBE inhibits LPS-induced Kupffer cell activation and subsequent inflammatory signaling. Importantly, the protective effects of GBE were more potent than those of silymarin, a known therapeutic agent for alcoholic liver diseases.

LB-9, Novel Probiotic Lactic Acid Bacteria, Ameliorates Dextran Sodium Sulfate-Induced Colitis in Mice by Inhibiting TNF-α-Mediated Apoptosis of Intestinal Epithelial Cells.

Inflammatory bowel disease (IBD), including ulcerative colitis (UC) and Crohn's disease, is a group of chronic and relapsing inflammatory conditions within the gastrointestinal tract. An increase in intestinal epithelial cell (IEC) apoptosis is a major characteristic of UC. Tumor necrosis factor-α (TNF-α) plays an essential role in the regulation of apoptosis. Aberrant activation of the immune response to resident microflora contributes to overproduction of TNF-α in the mucosal tissue of the gastrointestinal tract; a hallmark of UC. There are no curative medications for IBD. Thus, establishment of novel strategies for the treatment of this disease is imperative. Lactic acid bacteria (LAB) have been characterized as probiotics that can alleviate imbalances in indigenous microflora in UC, exhibiting beneficial effects for the treatment and prevention of IBD. In this study, we elucidate the potential of LB-9, a novel probiotic LAB, to protect against colitis development using a dextran sodium sulfate (DSS)-induced mouse model of UC. Treatment using LB-9 reduced clinical symptoms of colitis. In addition, both colitis-induced and NF-κB-mediated IEC apoptosis was markedly reduced in mice treated with LB-9. Moreover, these results were closely associated with reduced TNF-α levels. Our study demonstrates that the LB-9 probiotic exhibits therapeutic potential for UC through suppression of TNF-α-mediated IEC apoptosis in a murine DSS-induced colitis model, with important biological implications for treatment of IBD in humans.

Effects of Orally-Administered Bifidobacterium animalis subsp. lactis Strain BB12 on Dextran Sodium Sulfate-Induced Colitis in Mice.

Inflammatory bowel disease, including Crohn's disease and ulcerative colitis (UC), is a chronically relapsing inflammatory disorder of the gastrointestinal tract. Intestinal epithelial cells (IECs) constitute barrier surfaces and play a critical role in maintaining gut health. Dysregulated immune responses and destruction of IECs disrupt intestinal balance. Dextran sodium sulfate (DSS) is the most widely used chemical for inducing colitis in animals, and its treatment induces colonic inflammation, acute diarrhea, and shortening of the intestine, with clinical and histological similarity to human UC. Current treatments for this inflammatory disorder have poor tolerability and insufficient therapeutic efficacy, and thus, alternative therapeutic approaches are required. Recently, dietary supplements with probiotics have emerged as promising interventions by alleviating disturbances in the indigenous microflora in UC. Thus, we hypothesized that the probiotic Bifidobacterium animalis subsp. lactis strain BB12 could protect against the development of colitis in a DSS-induced mouse model of UC. In the present study, oral administration of BB12 markedly ameliorated DSS-induced colitis, accompanied by reduced tumor necrosis factor-α-mediated IEC apoptosis. These findings indicate that the probiotic strain BB12 can alleviate DSS-induced colitis and suggest a novel mechanism of communication between probiotic microorganisms and intestinal epithelia, which increases intestinal cell survival by modulating pro-apoptotic cytokine expression.

Amelioration of High Fructose-Induced Cardiac Hypertrophy by Naringin.

Heart failure is a frequent unfavorable outcome of pathological cardiac hypertrophy. Recent increase in dietary fructose consumption mirrors the rise in prevalence of cardiovascular diseases such as cardiac hypertrophy leading to concerns raised by public health experts. Mitochondria, comprising 30% of cardiomyocyte volume, play a central role in modulating redox-dependent cellular processes such as metabolism and apoptosis. Furthermore, mitochondrial dysfunction is a key cause of pathogenesis of fructose-induced cardiac hypertrophy. Naringin, a major flavanone glycoside in citrus species, has displayed strong antioxidant potential in models of oxidative stress. In this study, we evaluated protective effects of naringin against fructose-induced cardiac hypertrophy and associated mechanisms of action, using in vitro and in vivo models. We found that naringin suppressed mitochondrial ROS production and mitochondrial dysfunction in cardiomyocytes exposed to fructose and consequently reduced cardiomyocyte hypertrophy by regulating AMPK-mTOR signaling axis. Furthermore, naringin counteracted fructose-induced cardiomyocyte apoptosis, and this function of naringin was linked to its ability to inhibit ROS-dependent ATM-mediated p53 signaling. This result was supported by observations in in vivo mouse model of cardiac hypertrophy. These findings indicate a novel role for naringin in protecting against fructose-induced cardiac hypertrophy and suggest unique therapeutic strategies for prevention of cardiovascular diseases.

Root bark of Ulmus davidiana var. japonica restrains acute alcohol-induced hepatic steatosis onset in mice by inhibiting ROS accumulation.

Alcohol-induced hepatic steatosis and inflammation are key drivers of alcohol-induced liver injury, mainly caused by oxidative stress. The roots bark of Ulmus davidiana var. japonica is well known for its substantial antioxidative and antitumorigenic potency. In this study, we examined whether this plant can ameliorate alcohol-induced liver injuries characterized by hepatic steatosis and inflammation through its antioxidative activity. C57BL/6J mice were treated with the root bark extract of Ulmus davidiana var. japonica (RUE; 100 mg of extract/kg bodyweight; oral gavage) and alcohol (1 g/kg of bodyweight; oral gavage) for 5 days. Markers of acute alcohol-induced hepatic steatosis were determined and putative molecular mechanisms responsible for the protection of RUE were investigated. RUE noticeably protected against alcohol-induced hepatic steatosis and inflammation. Reactive oxygen species (ROS), over-produced by alcohol, negatively orchestrated various signaling pathways involved in the lipid metabolism and inflammation. These pathways were restored through the ROS scavenging activity of RUE in the liver. In particular, the expression of lipogenic genes (e.g., SREBP-1, ACC, and FAS) and inflammatory cytokines (e.g., IL-1ß, and NF-κB p65) significantly decreased with RUE treatment. Conversely, the expression of fatty acid oxidation-related genes (e.g., SIRT1, AMPKα, and PGC1α) were increased in mice treated with RUE. Thus, the results indicate that RUE counteracts and thus attenuates alcoholic hepatic steatosis onset in mice, possibly by suppressing ROS-mediated steatosis and inflammation.

Blood Pressure-Lowering Effects of Alacalase-Hydrolyzed Camellia Seed Hull In Vitro and in Spontaneous Hypertensive Rats.

High blood pressure is one of the major risk factors for various diseases and angiotensin-converting enzyme (ACE) plays a critical role in blood pressure regulation. In our study, the responsive surface methodology was adopted to establish optimal Alcalase-hydrolysis conditions of camellia seed hull against ACE activity. The optimum conditions are hydrolysis temperature of 50.98°C, enzyme/substrate ratio of 2.85%, and hydrolysis pH of 7.12. In an animal feeding study, spontaneously hypertensive rats were treated with either a low or high dose of hydrolyzed Camellia japonica seed cake over 5 weeks. Even though systolic blood pressure was not statistically different, the high dose of C. japonica hydrolysate lowered diastolic blood pressure (106 ± 4.4 mmHg vs. 145 ± 5.9 mmHg) at the 5th week. A similar trend was also observed in serum ACE activity. Considering that this camellia seed hull is a major resource of this plant, our study provides important data to utilize this plant for both academic and industrial applications.

Antiobesity Effect of Garlic Extract Fermented by Lactobacillus plantarum BL2 in Diet-Induced Obese Mice.

Obesity is viewed as a serious public health problem. This study aimed to investigate the antiobesity effects of fermented garlic extract by lactic acid bacteria (LAFGE) on obesity. Male C57BL/6J mice were fed with high-fat diet (HFD) to induce obesity. The HFD-induced obese mice were orally administrated with 250 or 500 mg/kg LAFGE for 8 weeks. Feeding HFD-fed mice with 250 or 500 mg/kg LAFGE reduced body weight by 14% and 18%, respectively, compared to HFD. HFD-fed mice with 500 mg/kg LAFGE administration had lower epididymal, retroperitoneal, and mesenteric adipose tissue mass by 36%, 44%, and 63%, respectively, compared to HFD. The concentration of plasma triacylglyceride and total cholesterol was significantly lower in the HFD-fed mice with LAFGE administration. Moreover, LAFGE supplementation suppressed adipogenesis by downregulation in mRNA and protein expression of PPARγ, C/EBPα, and lipogenic proteins, including SREBP-1c, FAS, and SCD-1. Based on these findings, LAFGE may ameliorate diet-induced obesity by inhibiting adipose tissue hypertrophy by suppressing adipogenesis.

Circadian clock, cancer, and chemotherapy.

The circadian clock is a global regulatory system that interfaces with most other regulatory systems and pathways in mammalian organisms. Investigations of the circadian clock-DNA damage response connections have revealed that nucleotide excision repair, DNA damage checkpoints, and apoptosis are appreciably influenced by the clock. Although several epidemiological studies in humans and a limited number of genetic studies in mouse model systems have indicated that clock disruption may predispose mammals to cancer, well-controlled genetic studies in mice have not supported the commonly held view that circadian clock disruption is a cancer risk factor. In fact, in the appropriate genetic background, clock disruption may instead aid in cancer regression by promoting intrinsic and extrinsic apoptosis. Finally, the clock may affect the efficacy of cancer treatment (chronochemotherapy) by modulating the pharmacokinetics and pharmacodynamics of chemotherapeutic drugs as well as the activity of the DNA repair enzymes that repair the DNA damage caused by anticancer drugs.

Circadian clock control of the cellular response to DNA damage.

Mammalian cells possess a cell-autonomous molecular clock which controls the timing of many biochemical reactions and hence the cellular response to environmental stimuli including genotoxic stress. The clock consists of an autoregulatory transcription-translation feedback loop made up of four genes/proteins, BMal1, Clock, Cryptochrome, and Period. The circadian clock has an intrinsic period of about 24 h, and it dictates the rates of many biochemical reactions as a function of the time of the day. Recently, it has become apparent that the circadian clock plays an important role in determining the strengths of cellular responses to DNA damage including repair, checkpoints, and apoptosis. These new insights are expected to guide development of novel mechanism-based chemotherapeutic regimens.

Enhancement of antibody responses to Bacillus anthracis protective antigen domain IV by use of calreticulin as a chimeric molecular adjuvant.

The generation of protective humoral immune responses against the receptor-binding domain (domain IV) of protective antigen [PA(dIV)] of Bacillus anthracis represents a plausible approach against anthrax toxin. In the current study, we have developed a naked DNA vaccine encoding calreticulin (CRT) linked to PA(dIV) of Bacillus anthracis [CRT/PA(dIV)]. We transfected a human embryonic kidney cell line (HEK 293) with CRT/PA(dIV) DNA and performed Western blotting and confocal microscopy analysis. We found that linkage of CRT to PA(dIV) targets PA(dIV) to the endoplasmic reticulum, resulting in secretion of the chimeric CRT/PA(dIV) protein. We then evaluated the ability of CRT/PA(dIV) DNA to generate PA(dIV)-specific antibody responses and protective immunity against lethal anthrax toxin (PA plus lethal factor) challenge. We found that mice immunized with CRT/PA(dIV) DNA were capable of rapidly inducing significantly higher PA(dIV)-specific antibody responses than mice immunized with PA(dIV) DNA alone. Furthermore, we observed that this enhanced antibody response generated by CRT/PA(dIV) DNA was CD4 dependent, since CD4 knockout mice demonstrated a significant reduction in antibody responses. In addition, analysis of the titers and avidity maturation of the induced PA-specific antibodies revealed that vaccination with CRT/PA(dIV) DNA vaccine accelerated the avidity maturation of antibodies to PA(dIV) compared to vaccination with PA(dIV) DNA. Importantly, the enhanced antibody responses correlated to protective immunity against lethal anthrax toxin challenge. Thus, DNA vaccines encoding CRT linked to PA(dIV) may dramatically enhance PA-specific protective antibody responses. Our results have significant clinical applications for biodefense against anthrax toxin.