Lactobacillus gasseri BNR17 Ameliorates Dexamethasone-Induced Muscle Loss in BALB/c Mice and C2C12 Myotubes.

This study aimed to investigate the effects and mechanism of Lactobacillus gasseri BNR17, a probiotic strain isolated from human breast milk, on dexamethasone-induced muscle loss in mice and cultured myotubes. BALB/c mice were intraperitoneally injected with dexamethasone, and orally administered L. gasseri BNR17 for 21 days. L. gasseri BNR17 treatment ameliorated dexamethasone-induced decline in muscle function, as evidenced by an increase in forelimb grip strength, treadmill running time, and rotarod retention time in both female and male mice. In addition, L. gasseri BNR17 treatment significantly increased the mass of the gastrocnemius and quadriceps muscles. Dual-energy X-ray absorptiometry showed a significant increase in lean body mass and a decrease in fat mass in both whole body and hind limb after treatment with L. gasseri BNR17. It was found that L. gasseri BNR17 treatment downregulated serum myostatin level and the protein degradation pathway composed of muscle-specific ubiquitin E3 ligases, MuRF1 and MAFbx, and their transcription factor FoxO3. In contrast, L. gasseri BNR17 treatment upregulated serum insulin-like growth factor-1 level and Akt-mTOR-p70S6K signaling pathway involved in protein synthesis in muscle. As a result, L. gasseri BNR17 treatment significantly increased the levels of major muscular proteins such as myosin heavy chain and myoblast determination protein 1. Consistent with in vivo results, L. gasseri BNR17 culture supernatant significantly ameliorated dexamethasone-induced C2C12 myotube atrophy in vitro. In conclusion, L. gasseri BNR17 ameliorates muscle loss by downregulating the protein degradation pathway and upregulating the protein synthesis pathway.

Effect of moderate to severe atopic dermatitis on the prognosis of egg allergy resolution

BACKGROUND: Few studies have examined the effect of atopic dermatitis (AD) on the resolution of food allergies in Asia, and the predictors of egg allergy resolution are not yet well defined. OBJECTIVE: We evaluated whether AD severity could predict the resolution of egg allergy. METHODS: This retrospective cohort study included infants under 24 months of age diagnosed with IgE-mediated egg white allergy. We included subjects who completed a 60-month follow-up. Open oral food challenges (OFCs) and serologic tests were performed at the time of initial diagnosis and at 36 ± 3 and 60 ± 3 months. RESULTS: We analyzed 68 patients (39 boys and 29 girls). OFCs were performed in 88.2% of the patients. The egg allergy remission rates were 23.5% and 47.1% by 3 and by 5 years of age, respectively. Persistent egg allergy was significantly associated with moderate to severe AD and house dust mite sensitization. Kaplan-Meier curve analysis revealed that patients with moderate to severe AD had higher persistent egg allergy rates than patients with no and mild AD (p = 0.012). Multivariable analysis identified moderate to severe AD as strongly associated with persistent egg allergy (p = 0.001). CONCLUSIONS: In this study, 47.1% of infants had resolved egg white allergies at 60 months. Moderate to severe AD may be a practical and important prognostic factor for persistent egg allergy in clinical settings.

Effect of Judo Athletes' Psychological Function on Sports Coping Skills: Moderated Mediating Effect of Tension.

This study aimed to investigate the effects of Judo athletes' psychological function on sports coping skills through self-management: the moderated mediating effect of tension. A total of 124 participants (66 males and 58 females) were included, comprising high school students, college students, and judo team players (age 16 to 30, 20.51 ± 3.17) in the Republic of Korea. The psychological function was measured using the Profile of Mood Test, Athletes' Self-Management Questionnaire, and Athletic Coping Skills Inventory-28. The results of the analysis of the moderating effect of the athlete's self-management behavior showed that tension had a moderating effect on the relationship between the athlete's self-management behavior and sports coping skills. The mediating effect analysis revealed a mediating effect of self-management behavior on the relationship between player vitality and sports coping skills. It was also confirmed that tension had a moderating effect on athletes' self-management behavior and sports coping skills. Therefore, it was confirmed that the higher the self-management, the more moderated the mediating effect on sports coping skills. In conclusion, it was confirmed that psychological function affects sports coping skills, and thereby, the mediating effect of the athlete's self-management behavior is regulated by tension. In future research, it will be necessary to study the sports coping ability and performance of judo athletes according to tension control.

Protective Effects of Korean Herbal Remedy against Airway Inflammation in an Allergic Asthma by Suppressing Eosinophil Recruitment and Infiltration in Lung.

The increasing prevalence of allergic asthma has become the world's major health issue. Current treatments for allergic asthma focus on treating symptoms, while permanent cures still remain undiscovered. In this study, we investigated the effect of Korean traditional herbal remedy, Pyunkang-tang (PGT)-composed of six plants-on asthma alleviation in a mouse model. The PGT mixture was orally gavaged to mice (PM group, 20 mg/mouse/day) from 7 days before sensitization with ovalbumin (OVA) (day -7). On day 0 and day 14, mice from OVA-control (n = 9) and PM group (n = 8) were sensitized with OVA and alum through intraperitoneal injection. On days 18~20, OVA was challenged to mice through nasal injection and sacrificed next day. Cell profile in lung tissue was analyzed by flow cytometry and RT-qPCR analysis, and the number of eosinophils and expression of siglec-F were significantly reduced in the PM group. Lung tissue was examined with hematoxylin and eosin (H&E) and Alcian blue/periodic acid-Schiff (AB-PAS) staining. Noticeably reduced eosinophil infiltration around bronchioles was displayed in the PM group compared to the OVA-control group. Furthermore, PGT-treated mice showed a significant reduction in IL-13 and a mild reduction in IL-5 in lungs. A decreasing tendency of IL-5/13 (+) CD4+ T cells and IL-13(+) innate lymphoid cells (ILCs) and a significant reduction in IL5(+) ILCs were also observed. When treating PGT on murine lung epithelial cells stimulated by papain, there was a significant reduction in IL-33 mRNA expression levels. Taken together, oral delivery of PGT successfully alleviated asthmatic responses provoked by OVA in a mouse model and could lead to novel therapies for allergic asthma.

Effect of an Integrated Healthcare Program for Korean Rural Older Adults: A Quasi-Experimental Study.

Studies have been conducted on the development of healthcare programs for older adults in rural areas, not only in Asia but also in Europe and the United States. However, these reports have been limited by largely non-comprehensive results, lack of demand surveys, or programs with no systematic development. The purpose of this study was to develop an integrated healthcare program for rural older adults and investigate the effects of the program. A nonequivalent control group pretest-posttest design was used. Subjects were aged over 65 and lived in the rural community. The integrated healthcare program involved 12 three-hour sessions over 12 weeks. Compared with the control group, the experimental group demonstrated significant differences in both upper extremities strengths (t = 2.74, p = 0.008; t = 2.03, p = 0.047), static balance (z = -2.38, p = 0.017), dynamic balance (t = -4.82, p < 0.001), loneliness (t = -3.02, p = 0.003), and role self-efficacy (t = 2.39, p = 0.020), but no differences for ego integration (t = 1.51, p = 0.137). To improve physical, mental, and social health of the rural older adults, we developed an integrated healthcare program. The program improved physical functions, loneliness, and role self-efficiency of the rural older adults. Therefore, it is recommended that healthcare professionals actively apply this program in primary healthcare institutes and elsewhere.

Invariant NKT Cells Functionally Link Microbiota-Induced Butyrate Production and Joint Inflammation.

Emerging evidence indicates that the gut microbiota contributes to the regulation of joint inflammation by modulating the function of immune cells. However, the mechanism by which the microbiota regulates joint inflammation is unclear. To address this, we investigated the effect of the gut microbiota on Ab-induced arthritis (AIA). Feeding mice a high-fiber diet attenuated AIA in a microbiota-dependent manner. Among the short-chain fatty acids produced by the microbiota, butyrate suppressed cytokine production by invariant NKT (iNKT) cells by inhibiting class I histone deacetylases. Furthermore, butyrate alleviated AIA in wild-type, but not iNKT cell-deficient Jα18 knockout (KO), mice. Adoptive transfer of butyrate-pretreated iNKT cells had no effect on AIA in Jα18 KO mice, whereas transfer of untreated iNKT cells into Jα18 KO mice restored AIA. In conclusion, our data indicate that gut microbiota-induced butyrate production attenuates AIA by inhibiting cytokine production by iNKT cells. Thus, the microbiota/butyrate/iNKT cell axis may be a therapeutic target for joint inflammation.

Identification and characterization of prescription drugs that change levels of 7-dehydrocholesterol and desmosterol.

Regulating blood cholesterol (Chol) levels by pharmacotherapy has successfully improved cardiovascular health. There is growing interest in the role of Chol precursors in the treatment of diseases. One sterol precursor, desmosterol (Des), is a potential pharmacological target for inflammatory and neurodegenerative disorders. However, elevating levels of the precursor 7-dehydrocholesterol (7-DHC) by inhibiting the enzyme 7-dehydrocholesterol reductase is linked to teratogenic outcomes. Thus, altering the sterol profile may either increase risk toward an adverse outcome or confer therapeutic benefit depending on the metabolite affected by the pharmacophore. In order to characterize any unknown activity of drugs on Chol biosynthesis, a chemical library of Food and Drug Administration-approved drugs was screened for the potential to modulate 7-DHC or Des levels in a neural cell line. Over 20% of the collection was shown to impact Chol biosynthesis, including 75 compounds that alter 7-DHC levels and 49 that modulate Des levels. Evidence is provided that three tyrosine kinase inhibitors, imatinib, ponatinib, and masitinib, elevate Des levels as well as other substrates of 24-dehydrocholesterol reductase, the enzyme responsible for converting Des to Chol. Additionally, the mechanism of action for ponatinib and masitinib was explored, demonstrating that protein levels are decreased as a result of treatment with these drugs.

Effects of Exposure of Formaldehyde to a Rat Model of Atopic Dermatitis Induced by Neonatal Capsaicin Treatment.

Atopic dermatitis is chronically relapsing pruritic eczema and prevails around the world especially in developed countries. Complex interactions between genetic and environmental factors are known to play an important role in the pathophysiology of atopic dermatitis. However, we still lack a detailed picture of the pathogenesis of this disease. Thus, it is of importance to develop appropriate animal models for elucidating the progression of atopic dermatitis. Moreover, investigating the effect of environmental factors such as air pollutants on atopic dermatitis expands understanding of the disease. Here, we describe a method for inducing atopic dermatitis in rats with neonatal capsaicin treatment and a protocol for exposure of a constant concentration of formaldehyde to rats to reveal effects on the development of atopic dermatitis in infantile and adolescent periods. These protocols have been successfully applied to several experiments and can be used for other substances.

Effects of manual lymph drainage for abdomen on the brain activity of subjects with psychological stress.

[Purpose] The present study investigated the effects of manual lymph drainage for abdomen on electroencephalography in subjects with psychological stress. [Subjects and Methods] Twenty-eight subjects were randomly allocated to undergo a 20-min session of either manual lymph drainage or abdominal massage on a bed. [Results] Analysis of electroencephalograms from the manual lymph drainage group showed a significant increase in relaxation, manifested as an increase in average absolute, relative alpha activity and a decrease in relative gamma activity. [Conclusion] Our results suggest that the application of manual lymph drainage from the abdomen provides acute neural effects that increase relaxation in subjects with psychological stress.

Coffee Consumption and the Risk of Obesity in Korean Women.

Instant coffee mixes that contain sugar and non-dairy creamer account for 80-90% of the total coffee market in Korea. The objective of this study was to investigate the relationship between coffee consumption and obesity in Korean women. We included 5995 women who participated in a health screening examination at the Korean National Cancer Center between 2007 and 2016. Daily coffee consumption and the use of sugar and creamer in coffee was evaluated using a 106-item food frequency questionnaire. Obesity was assessed by body mass index (BMI), and abdominal obesity was assessed by waist circumference (WC). A multiple logistic regression model was used to calculate the odds ratio (OR) of obesity according to coffee consumption. After multivariate adjustment, high coffee consumption was positively associated with obesity as measured by BMI (≥3 cups vs. no drinks, OR = 2.52; 95% confidence interval (CI) = 1.91-3.34; p for the trend < 0.001) and abdominal obesity as measured by WC (≥3 cups vs. no drinks, OR = 2.11; 95% CI = 1.59-2.79; p for the trend < 0.001). The positive association between daily coffee consumption and obesity prevalence was not altered by menopause. The amount of coffee with additives consumed per day by Korean women was positively correlated with the prevalence of obesity, but causation cannot be determined due to the cross-sectional nature of the study design. The mechanism underlying the observed relationship is yet to be elucidated.

Vitamin D deficiency in children aged 6 to 12 years: single center's experience in Busan.

PURPOSE: This study investigated the prevalence and risk factors associated with vitamin D deficiency in children. METHODS: We analyzed the medical records of 330 patients from the age of 6 to 12, who visited the endocrinology clinic of the Department of Pediatrics at Pusan National University Hospital, from September, 2013 to May, 2014. According to their serum 25-hydroxyvitamin D (25(OH)D) levels, the patients were grouped into either the deficiency group (25(OH)D<20 ng/mL), or the sufficiency group (25(OH)D≥20 ng/mL). The differences between the 2 groups were compared. RESULTS: There were 195 patients (59.1%) who had vitamin D deficiency. Their mean serum 25(OH)D level was 14.86±3.20 ng/mL. The differences in sex, age, and pubertal status between the 2 groups were not statistically significant. Weight standard deviation score (SDS), and body mass index SDS, were significantly higher in the vitamin D deficiency group (P=0.002 for each), compared to the sufficiency group. Compared with Autumn, both Spring (odds ratio [OR], 9.7; 95% confidence interval [CI], 4.3-22.0), and Winter (OR, 5.9; 95% CI, 3.5-10.0), were risk factors for vitamin D deficiency. In multiple logistic regression analysis, only seasonal differences have been confirmed to have an effect on vitamin D deficiency. CONCLUSION: Vitamin D deficiency in children aged 6 to 12 years is very common. Spring and Winter are the most important risk factors for vitamin D deficiency. We suggest that it is necessary to supplement the guideline for the vitamin D intake according to our situation.

Inhibitors of 7-Dehydrocholesterol Reductase: Screening of a Collection of Pharmacologically Active Compounds in Neuro2a Cells.

A small library of pharmacologically active compounds (the NIH Clinical Collection) was assayed in Neuro2a cells to determine their effect on the last step in the biosynthesis of cholesterol, the transformation of 7-dehydrocholesterol (7-DHC) to cholesterol promoted by 7-dehydrocholesterol reductase, DHCR7. Of some 727 compounds in the NIH Clinical Collection, over 30 compounds significantly increased 7-DHC in Neuro2a cells when assayed at 1 µM. Active compounds that increased 7-DHC with a Z-score of +3 or greater generally gave rise to modest decreases in desmosterol and increases in lanosterol levels. Among the most active compounds identified in the library were the antipsychotic, antidepressant, and anxiolytic compounds that included perospirone, nefazodone, haloperidol, aripiprazole, trazodone, and buspirone. Fluoxetine and risperidone were also active at 1 µM, and another 10 compounds in this class of pharmaceuticals were identified in the screen at concentrations of 10 µM. Increased levels of 7-DHC are associated with Smith-Lemli-Opitz syndrome (SLOS), a human condition that results from a mutation in the gene that encodes DHCR7. The SLOS phenotype includes neurological deficits and congenital malformations, and it is linked to a higher incidence of autism spectrum disorder. The significance of the current study is that it identifies common pharmacological compounds that may induce a biochemical presentation similar to SLOS. Little is known about the side effects of elevated 7-DHC postdevelopmentally, and the elevated 7-DHC that results from exposure to these compounds may also be a confounder in the diagnosis of SLOS.

Erythropoiesis-stimulating Agents and Anemia in Patients with Non-dialytic Chronic Kidney Disease.

Anemia is common in patients with advanced chronic kidney disease (CKD). Though erythropoiesis-stimulating agents (ESAs) have been strongly endorsed in guidelines, it is of particular financial interest. Recently, the reimbursement of ESAs in non-dialytic patients was started by the Korean National Health Insurance System. Thus, we investigated the impact of the reimbursement of ESAs on the anemia care in non-dialytic CKD patients. Medical records of patients with advanced CKD (estimated GFR <30 mL/min/1.73 m(2)) were reviewed. Use of ESAs, blood transfusion, and hemoglobin concentrations were analyzed from one year prior to reimbursement to three years following. We used multivariable modified Poisson regression to estimate the utilization prevalence ratio (PRs). A total of 1,791 medical records were analyzed. The proportion of patients receiving ESAs increased from 14.8% before reimbursement to a peak 33.6% in 1 yr after reimbursement; thereafter, ESA use decreased to 22.4% in 3 yr after reimbursement (compared with baseline; PR, 2.19 [95% CI, 1.40-3.42]). In patients with Hb <10 g/dL, the proportion of receiving ESAs increased from 32.1% before reimbursement to 66.7% in 3 yr after reimbursement (compared with baseline; PR, 2.04 [95% CI, 1.25-3.32]). Mean hemoglobin concentrations were 10.06±1.54 g/dL before reimbursement and increased to 10.78±1.51 g/dL in 3 yr after the reimbursement change (P=0.001). However, the requirement of blood transfusion was not changed over time. With the reimbursement of ESAs, the advanced CKD patients were more likely to be treated with ESAs, and the hemoglobin concentrations increased.

Improvement in antiproliferative activity of Angelica gigas Nakai by solid dispersion formation via hot-melt extrusion and induction of cell cycle arrest and apoptosis in HeLa cells.

Angelica gigas Nakai (AGN) is one of the most popular herbal medicines and widely used as a functional food product. In this study, AGN was firstly processed by a low-temperature turbo mill and a hot melting extruder to reduce particle size and form solid dispersion (SD). Anticancer activity against HeLa cells was then examined. AGN-SD based on Soluplus was formed via hot-melt extrusion (HME) and showed the strongest cytotoxic effect on HeLa cells. In addition, the possible mechanism of cell death induced by AGN-SD on HeLa cells was also investigated. AGN-SD decreased cell viability, induced apoptosis, increased the production of reactive oxygen species, regulated the expression of Bcl-2 and Bax, and induced G2/M phase arrest in HeLa cells. This study suggested that AGN-SD based on Soluplus and the method to improve antiproliferative effect by SD formation via HME may be suitable for application in the pharmaceutical industry.

Spergularia marina induces glucagon-like peptide-1 secretion in NCI-H716 cells through bile acid receptor activation.

Spergularia marina Griseb. (SM) is a halophyte that grows in mud flats. The aerial portions of SM have been eaten as vegetables and traditionally used to prevent chronic diseases in Korea. However, there has been no scientific report that demonstrates the pharmacological effects of SM. Glucagon-like peptide-1 (GLP-1) is important for the maintenance of glucose and energy homeostasis through acting as a signal in peripheral and neural systems. To discover a functional food for regulating glucose and energy homeostasis, we evaluated the effect of an aqueous ethanolic extract (AEE) of SM on GLP-1 release from enteroendocrine NCI-H716 cells. In addition, we explored the Takeda G-protein-coupled receptor 5 (TGR5) agonist activity of AEE-SM in Chinese hamster ovary (CHO)-K1 cells transiently transfected with human TGR5. As a result, treatment of NCI-H716 cells with AEE-SM increased GLP-1 secretion and intracellular Ca(2+) and cyclic AMP (cAMP) levels in a dose-dependent manner. Transfection of NCI-H716 cells with TGR5-specific small interference RNA inhibited AEE-SM-induced GLP-1 secretion and the increase in Ca(2+) and cAMP levels. Moreover, AEE-SM showed that the TGR5 agonist activity in CHO-K1 cells transiently transfected with TGR5. The results suggest that AEE-SM might be a candidate for a functional food to regulate glucose and energy homeostasis.

Comparison of dietary food and nutrient intakes by supplement use in pregnant and lactating women in Seoul.

This study was performed to compare the dietary food and nutrient intakes according to supplement use in pregnant and lactating women in Seoul. The subjects were composed of 201 pregnant and 104 lactating women, and their dietary food intake was assessed using the 24-h recall method. General information on demographic and socioeconomic factors, as well as health-related behaviors, including the use of dietary supplements, were collected. About 88% and 60% of the pregnant and lactating women took dietary supplements, respectively. The proportion of dietary supplements used was higher in pregnant women with a higher level of education. After adjusting for potential confounders, among the pregnant women, supplement users were found to consume 45% more vegetables, and those among the lactating women were found to consume 96% more beans and 58% more vegetables. The intakes of dietary fiber and ß-carotene among supplement users were higher than those of non-users, by 23% and 39%, respectively. Among pregnant women, the proportion of women with an intake of vitamin C (from diet alone) below the estimated average requirements (EAR) was lower among supplement users [users (44%) vs. non-users (68%)], and the proportion of lactating women with intakes of iron (from diet alone) below the EAR was lower among supplement users [usesr (17%) vs. non-users (38%)]. These results suggest that among pregnant and lactating women, those who do not use dietary supplements tend to have a lower intake of healthy foods, such as beans and vegetables, as well as a lower intake of dietary fiber and ß-carotene, which are abundant in these foods, and non-users are more likely than users to have inadequate intake of micro-nutrient such as vitamin C and iron.

Regulation of signaling molecules associated with insulin action, insulin secretion and pancreatic ß-cell mass in the hypoglycemic effects of Korean red ginseng in Goto-Kakizaki rats.

ETHNOPHARMACOLOGICAL RELEVANCE: Korean red ginseng (KRG) has long history as herbal remedy for antidiabetic effect. AIM OF THE STUDY: To study molecular mechanisms by which KRG ameliorates diabetes mellitus, we investigated whether the supplementation with the aqueous extract of KRG as a dietary admixture (1%, w/w) regulates the expressions of signaling molecules that are associated with insulin action, insulin secretion and pancreatic ß-cell mass in spontaneously diabetic Goto-Kakizaki (GK) rats. METHODS: An aqueous extract of KRG was supplemented for the estimated dosage to be 0.2 g/kg rat/day beginning at 5 weeks of age for 12 weeks in male GK rats. Plasma glucose levels were measured every 4 weeks. The expressions of signaling molecules that are associated with insulin action, insulin secretion and ß-cell mass in tissues were determined by Western blotting. RESULTS: The 12-week supplementation with KRG significantly (P<0.05) decreased blood glucose compared to control. It up-regulated the expression of glucose transporter (GLUT) 4 in adipose tissue, and down-regulated the expression of protein tyrosine phosphatases (PTP)-1B in adipose tissue and skeletal muscle. It also up-regulated the expression of insulin and down-regulated the expression of uncoupling protein (UCP) 2, Bax and poly (ADP-ribose) polymerase (PARP) in pancreas. CONCLUSIONS: These results suggest that GLUT4, PTP-1B, insulin, UCP2, Bax and PARP may be the primary targets of KRG that result in increase in insulin action and in insulin secretion, and decrease in ß-cell mass, and that cause the normalization in glucose homeostasis.

RG-II from Panax ginseng C.A. Meyer suppresses asthmatic reaction.

In asthma, T helper 2 (T(H)2)-type cytokines such as interleukin (IL)-4, IL-5, and IL-13 are produced by activated CD4(+) T cells. Dendritic cells played an important role in determining the fate of naive T cells into either T(H)1 or T(H)2 cells. We determined whether RG-II regulates the T(H)1/T(H)2 immune response by using an ovalbumin-induced murine model of asthma. RG-II reduced IL-4 production but increased interferon- gamma production, and inhibited GATA-3 gene expression. RG-II also inhibited asthmatic reactions including an increase in the number of eosinophils in bronchoalveolar lavage fluid, an increase in inflammatory cell infiltration in lung tissues, airway luminal narrowing, and airway hyperresponsiveness. This study provides evidence that RG-II plays a critical role in ameliorating the pathogenic process of asthmatic inflammation in mice. These findings provide new insights into the immunotherapeutic role of RG-II in terms of its effects in a murine model of asthma.

Synergistic effects between silibinin and antibiotics on methicillin-resistant Staphylococcus aureus isolated from clinical specimens.

Methicillin-resistant Staphylococcus aureus (MRSA) is a dangerous microorganism, and creates serious medical problems. It causes many types of infections in humans and often acquires multi-drug resistance. In this study, silibinin was evaluated against 20 clinical isolates of MRSA, either alone or in combination with ampicillin or oxacillin, using a checkerboard assay. The silibinin exhibited good activity against isolates of MRSA, and MRSA ATCC33952 and MSSA ATCC25923, with minimum inhibitory concentrations/minimum bactericidal concentrations (MICs/MBCs) ranging between 2-8/4-16 µg/mL, for ampicillin 2-1024/2-2048 µg/mL, and for oxacillin 0.25-32/0.5-64 µg/mL. The range of MIC(50) and MIC(90) were 0.5-4 µg/mL and 2-8 µg/mL, respectively. The MICs/MBCs for the combination of silibinin plus oxacillin or ampicillin were reduced by ≥4-fold against the MRSA isolates tested, demonstrating a synergistic effect, as defined by a fractional inhibitory concentration index (FICI) of ≤0.5. Furthermore, a time-kill study evaluating the growth of the tested bacteria showed that growth was completely attenuated after 2-5 h of treatment with the 1/2 MIC of silibinin, regardless of whether it was administered alone or with oxacillin (1/2 MIC) or ampicillin (1/2 MIC). In conclusion, silibinin exerted synergistic effects when administered with oxacillin or ampicillin and the antibacterial activity and resistant regulation of silibinin against clinical isolates of MRSA might be useful in controlling MRSA infections.

Synergistic effect between clove oil and its major compounds and antibiotics against oral bacteria.

BACKGROUND: Essential oils have been found to be antibacterial, antifungal, spasmolytic, and antiplasmodial activity and therapeutic effect in cancer treatment. OBJECTIVE AND DESIGN: In this study, clove oil and its major compounds, eugenol and ß-caryophyllene were evaluated against oral bacteria, either alone or in combination with ampicillin or gentamicin, via checkerboard and time kill assay. RESULTS: The antibacterial activity of the clove oil was higher than ß-caryophyllene but was similar to eugenol against all tested oral bacteria. Furthermore, the MIC and MBC were reduced to one half-one sixteenth as a result of the combination of clove oil or eugenol with antibiotics. The synergistic interaction was verified by time kill studies using the clove oil or eugenol with antibiotics. 60 min of treatment with MIC of the clove oil or eugenol with ampicillin or gentamicin resulted in an increase in the rate of killing in units of CFU/mL to a greater degree than was observed with alone. CONCLUSION: The results suggest that the clove oil and eugenol could be employed as a natural antibacterial agent against cariogenic and periodontopathogenic bacteria.