A Review of Natural Products for Prevention of Acute Kidney Injury.

BACKGROUND AND OBJECTIVES: acute kidney injury (AKI), formerly called acute renal failure (ARF), is commonly defined as an abrupt decline in renal function, clinically manifesting as a reversible acute increase in nitrogen waste products-measured by blood urea nitrogen (BUN) and serum creatinine levels-over the course of hours to weeks. AKI occurs in about 20% of all hospitalized patients and is more common in the elderly. Therefore, it is necessary to prevent the occurrence of AKI, and to detect and treat early, since it is known that a prolonged period of kidney injury increases cardiovascular complications and the risk of death. Despite advances in modern medicine, there are no consistent treatment strategies for preventing the progression to chronic kidney disease. Through many studies, the safety and efficacy of natural products have been proven, and based on this, the time and cost required for new drug development can be reduced. In addition, research results on natural products are highly anticipated in the prevention and treatment of various diseases. In relation to AKI, many papers have reported that many natural products can prevent and treat AKI. CONCLUSIONS: in this paper, the results of studies on natural products related to AKI were found and summarized, and the mechanism by which the efficacy of AKI was demonstrated was reviewed. Many natural products show that AKI can be prevented and treated, suggesting that these natural products can help to develop new drugs. In addition, we may be helpful to elucidate additional mechanisms and meta-analysis in future natural product studies.

Effects of Panax ginseng on the nerve growth factor expression in testosterone induced benign prostatic hyperplasia.

The prostatic hyperplasia in benign prostatic hyperplasia (BPH) leads to obstructive micturition symptoms. Previous studies showed that pontine micturition center (PMC), ventrolateral periaqueductal gray (vlPAG), and medial preopticnucleus (MPA) regions in the brain have been known to regulate the urinary bladder function. The present study shows the influences of Panax ginseng on nerve growth factor (NGF) expressions in PMC, vlPAG, and MPA regions in the brain. Wistar rats were used for the present study. The rats split into four groups; 4 groups (n = 6) in control group, BPH-induced group, BPH-induced and P. ginseng-treated group, and BPH-induced and finasteride-treated group. BPH in rats was induced by testosterone and the animals were evaluated for NGF expression in PMC, vlPAG, and MPA regions in the brain. The NGF expression was identified using immunohistochemistry (IHC). The NGF expression by IHC showed spots with dark brown color. In our results, NGF expressions in PMC, vlPAG, and MPA regions in the brainstem of the BPH-induced group showed increase than the control animal. These increased NGF expressions in three regions were decreased using treatment with P. ginseng (200 mg/kg). These results suggest that P. ginseng has therapeutic effects on the symptoms of BPH and is associated with the regulation of NGF expression in the brain. In conclusion, the administration of P. ginseng helps nerve growth factor activation.

Association Between Alcohol Consumption and Metabolic Syndrome in a Community-Based Cohort of Korean Adults.

BACKGROUND The relationship between alcohol consumption and metabolic syndrome (MetS) remains controversial. This study investigated the relationship between alcohol consumption and MetS components and prevalence. MATERIAL AND METHODS We analyzed 10 037 subjects (3076 MetS and 6961 non-MetS) in a community-based cohort. MetS was defined according to the ATP III Guidelines. Subjects were divided according to amount of alcohol consumption; non-drinker, very light (0.1-5.0 g/day), light (5.1-15.0 g/day), moderate (15.1-30.0 g/day), and heavy drinker (>30 g/day). Multiple logistic regression models were performed to estimate odds ratios (ORs) and confidence intervals (CIs). The analyses were performed in men and women separately. SPSS statistical software was used for analyses. RESULTS The prevalence of MetS in both males and females was associated with alcohol drinking status (p<0.0001). Amount of alcohol consumption (0.1-5.0 g/day) was significantly associated with lower prevalence of MetS in both genders compared to non-drinkers. Amount of alcohol consumption (>30.0 g/day) did not show a significant association with prevalence of MetS. However, alcohol consumption (>30.0 g/day) showed an association with glucose and HDL cholesterol among the components of MetS. CONCLUSIONS Our results indicate that alcohol drinking (0.1-5.0 g/day) contributed to decrease prevalence of MetS and components, including triglyceride and HDL cholesterol.

Genetic Polymorphisms of Glutathione-Related Enzymes (GSTM1, GSTT1, and GSTP1) and Schizophrenia Risk: A Meta-Analysis.

The association between polymorphisms of glutathione-related enzyme (GST) genes and the risk of schizophrenia has been investigated in many published studies. However, their results were inconclusive. Therefore, we performed a meta-analysis to explore the association between the GSTM1, GSTT1, and GSTP1 polymorphisms and the risk of schizophrenia. Twelve case-control studies were included in this meta-analysis. The odds ratio (OR) and 95% confidence interval (95% CI) were used to investigate the strength of the association. Our meta-analysis results revealed that GSTM1, GSTT1, and GSTP1 polymorphisms were not related to risk of schizophrenia (p > 0.05 in each model). Further analyses based on ethnicity, GSTM polymorphism showed weak association with schizophrenia in East Asian population (OR = 1.314, 95% CI = 1.025-1.684, p = 0.031). In conclusion, our meta-analysis indicated the GSTM1 polymorphism may be the only genetic risk factor for schizophrenia in East Asian population. However, more meta-analysis with a larger sample size were needed to provide more precise evidence.

ACE insertion/deletion polymorphism is associated with periodontal disease in Korean population.

OBJECTIVE: Angiotensin-converting enzyme (ACE) is the core enzyme in the renin-angiotensin system (RAS), which catalyzes the production of angiotensin II (Ang II). The aim of this study was to determine whether ACE gene is associated with the development of the periodontal disease. DESIGN: To investigate whether ACE is involved in the development of the periodontal disease, 199 periodontal disease patients and 165 control subjects were studied. The ACE insertion/deletion polymorphism was analyzed using polymerase chain reaction (PCR). SNPStats and SPSS 18.0 were used for the analysis of genetic data. Logistic regression models were performed to determine odds ratio (OR), 95% confidence interval (CI), and P value. RESULTS: Genotypic frequencies of I/I, I/D, and D/D were 25.4%, 42.3%, and 32.3% vs. 35.3%, 41.7%, and 23.1% (periodontal disease group vs. control group), respectively. In the genotype analysis of the ACE insertion/deletion polymorphism, codominant and log-additive models both showed significant association with periodontal disease [OR = 1.94, 95% CI = 1.05-3.61, P=0.036 in the codominant model (I/I vs. D/D); OR = 1.39, 95% CI = 1.02-1.90, P = 0.034 in the log-additive model (I/I vs. I/D vs. D/D)]. CONCLUSIONS: These results suggest that the ACE insertion/deletion polymorphism may be associated with the susceptibility to the periodontal disease in the Korean population.

Meta-analysis of association of the matrix metalloproteinase 2 (-735 C/T) polymorphism with cancer risk.

The association between matrix metalloproteinase 2 (MMP2) gene polymorphisms and cancer risk has been investigated in many published studies; however, the currently available results are inconclusive. Therefore, we performed a meta-analysis to provide conclusive evidence for an association between the MMP2 polymorphism (-735 C/T) and cancer risk. Sixteen case-control studies with 11792 individuals were included in this meta-analysis. The odds ratio (OR) and 95% confidence interval (95% CI) were used to investigate the strength of the association. Overall, the MMP2 polymorphism (-735 C/T) was not associated with cancer risk in any of the models. However, the subgroup analysis revealed that dominant model (C/T+T/T vs. C/C: OR=1.24, 95% CI=1.01-1.53) and codominant 1 model (C/T vs. C/C: OR=1.30, 95% CI=1.05-1.62) were significantly associated with cancer risk in the Caucasian population. In conclusion, our meta-analysis indicated that the MMP2 polymorphism (-735 C/T) might be genetic risk factor for the carcinogenesis in Caucasians. However, more studies with a larger sample size are needed to provide more precise evidence.

Evaluation of silica nanoparticle toxicity after topical exposure for 90 days.

Silica is a very common material that can be found in both crystalline and amorphous forms. Well-known toxicities of the lung can occur after exposure to the crystalline form of silica. However, the toxicities of the amorphous form of silica have not been thoroughly studied. The majority of in vivo studies of amorphous silica nanoparticles (NPs) were performed using an inhalation exposure method. Since silica NPs can be commonly administered through the skin, a study of dermal silica toxicity was necessary to determine any harmful effects from dermal exposures. The present study focused on the results of systemic toxicity after applying 20 nm colloidal silica NPs on rat skin for 90 days, in accordance with the Organization for Economic Cooperation and Development test guideline 411 with a good laboratory practice system. Unlike the inhalation route or gastrointestinal route, the contact of silica NPs through skin did not result in any toxicity or any change in internal organs up to a dose of 2,000 mg/kg in rats.

Zinc oxide nanoparticles: a 90-day repeated-dose dermal toxicity study in rats.

Zinc oxide (ZnO) works as a long-lasting, broad-spectrum physical sunblock, and can prevent skin cancer, sunburn, and photoaging. Nanosized ZnO particles are used often in sunscreens due to consumer preference over larger sizes, which appear opaque when dermally applied. Although the US Food and Drug Administration approved the use of nanoparticles (NPs) in sunscreens in 1999, there are ongoing safety concerns. The aim of this study was to evaluate the subchronic toxicity of ZnO NPs after dermal application according to the Organization for Economic Cooperation and Development Test Guidelines 411 using Good Laboratory Practice. Sprague Dawley rats were randomly divided into eight (one control, one vehicle control, three experimental, and three recovery) groups. Different concentrations of ZnO NPs were dermally applied to the rats in the experimental groups for 90 days. Clinical observations as well as weight and food consumption were measured and recorded daily. Hematology and biochemistry parameters were determined. Gross pathologic and histopathologic examinations were performed on selected tissues from all animals. Analyses of tissue were undertaken to determine target organ tissue distribution. There was no increased mortality in the experimental group. Although there was dose-dependent irritation at the site of application, there were no abnormal findings related to ZnO NPs in other organs. Increased concentrations of ZnO in the liver, small intestine, large intestine, and feces were thought to result from oral ingestion of ZnO NPs via licking. Penetration of ZnO NPs through the skin seemed to be limited via the dermal route. This study demonstrates that there was no observed adverse effect of ZnO NPs up to 1,000 mg/kg body weight when they are applied dermally.

Production of prostaglandin e(2) and i(2) is coupled with cyclooxygenase-2 in human follicular dendritic cells.

BACKGROUND: Prostaglandins (PGs) play pathogenic and protective roles in inflammatory diseases. The novel concept of PGs as immune modulators is being documented by several investigators. By establishing an in vitro experimental model containing human follicular dendritic cell-like cells, HK cells, we reported that HK cells produce prostaglandin E(2) (PGE(2)) and prostaglandin I(2) (PGI(2)) and that these PGs regulate biological functions of T and B cells. METHODS: To investigate the respective contribution of cyclooxygenase-1 (COX-1) and COX-2 to PGE(2) and PGI(2) production in HK cells, we performed siRNA technology to knock down COX enzymes and examined the effect on PG production. RESULTS: Both PGE(2) and PGI(2) productions were almost completely inhibited by the depletion of COX-2. In contrast, COX-1 knockdown did not significantly affect PG production induced by lipopolysaccharide (LPS). CONCLUSION: The current results suggest that mPGES-1 and PGIS are coupled with COX-2 but not with COX-1 in human follicular dendritic cell (FDC) and may help understand the potential effects of selective COX inhibitors on the humoral immunity.