Comparison of anti-diabetic effects of polysaccharides from corn silk on normal and hyperglycemia rats

Anti-Diabetic, Anti-Oxidant and Anti-Hyperlipidemic Activities of Flavonoids from Corn Silk on STZ-Induced Diabetic Mice

Corn silk is a well-known ingredient frequently used in traditional Chinese herbal medicines. This study was designed to evaluate the anti-diabetic, anti-oxidant and anti-hyperlipidemic activities of crude flavonoids extracted from corn silk (CSFs) on streptozotocin (STZ)-induced diabetic mice. The results revealed that treatment with 300 mg/kg or 500 mg/kg of CSFs significantly reduced the body weight loss, water consumption, and especially the blood glucose (BG) concentration of diabetic mice, which indicated their potential anti-diabetic activities. Serum total superoxide dismutase (SOD) and malondialdehyde (MDA) assays were also performed to evaluate the anti-oxidant effects. Besides, several serum lipid values including total cholesterol (TC), triacylglycerol (TG), low density lipoprotein cholesterol (LDL-C) were reduced and the high density lipoprotein cholesterol level (HDL-C) was increased. The anti-diabetic, anti-oxidant and anti-hyperlipidemic effect of the CSFs suggest a potential therapeutic treatment for diabetic conditions.

Toxicological evaluations of Stigma maydis (corn silk) aqueous extract on hematological and lipid parameters in Wistar rats

Despite the acclaimed phytotherapeutic attributes of Stigma maydis in folkloric medicine, there is paucity of information on its toxicity profile on hematological and lipid parameters. The toxicological effect of aqueous extract of corn silk at 100, 200 and 400 mg/kg body weight on hematological indices in Wistar rats were evaluated progressively at 24 h after 1, 7, 14, 21 and 28 days. Lipid parameters were also analyzed at the end of the experimental period. We observed that the extract did not exhibit any significant (p > 0.05) effect on red blood cells, hematocrit, hemoglobin, mean corpuscular volume, mean corpuscular hemoglobin, mean corpuscular hemoglobin concentration, and mean platelet volume at all the tested doses. The study however showed a significant increase in the serum levels of white blood cell, platelet, lymphocytes, high-density lipoprotein cholesterol; as well as feeding pattern in the animals, while the concentrations of total cholesterol, low-density lipoprotein cholesterol, and artherogenic index value were significantly lowered. These findings are suggestive of non-hematotoxic potential of the extract. Overall, the effect exhibited by corn silk extract in this study proved that, it is unlikely to be hematotoxic and could be a good candidature in the management of coronary heart diseases if consumed at the doses investigated.

Internet claims on dietary and herbal supplements in advanced nephropathy: truth or myth

BACKGROUND

The use of complementary/alternative medicine has garnered rising interest in recent years. Natural products including herbs, vitamins, and minerals are the most popularly consumed. The Internet is a ubiquitous source of information/market for these supplements.

AIM

To systematically evaluate the dietary and herbal supplement recommended for patients with CKD and ESRD on the Internet, and try to distinguish between the claim of the manufacturer and proven scientific data.

METHODS

A questionnaire assessing each website was formulated. Each product ingredient was recorded in the questionnaire by two independent reviewers and statistically analyzed.

RESULTS

Of the 184 websites, 28% claimed to decrease CKD progression, 60% did not advise to consult a doctor before taking the supplement, and >90% did not mention any potential drug interaction, disease interaction, or caution in use during pregnancy or in children. The ten common plant ingredients claiming to be beneficial in kidney diseases were uva ursi, dandelion, parsley, corn silk, juniper, celery, buchu, horsetail, marshmallow, and stinging nettle. In contrast to their claims, these substances were not adequately studied in humans. The available animal studies showed detrimental effects and potential drug interactions with commonly used medications in the CKD/ESRD population.

CONCLUSIONS

Nephrologists need to be cognizant of the lack of substantiated proven benefits of these substances and of the potential adverse effects in the animal models that can translate to the patients. Most importantly, the policy needs to change regarding the regulation of these products to prevent patient harm and misinformation.

Inhibitory effect of corn silk on skin pigmentation

In this study, the inhibitory effect of corn silk on melanin production was evaluated. This study was performed to investigate the inhibitory effect of corn silk on melanin production in Melan-A cells by measuring melanin production and protein expression. The corn silk extract applied on Melan-A cells at a concentration of 100 ppm decreased melanin production by 37.2% without cytotoxicity. This was a better result than arbutin, a positive whitening agent, which exhibited a 26.8% melanin production inhibitory effect at the same concentration. The corn silk extract did not suppress tyrosinase activity but greatly reduced the expression of tyrosinase in Melan-A cells. In addition, corn silk extract was applied to the human face with hyperpigmentation, and skin color was measured to examine the degree of skin pigment reduction. The application of corn silk extract on faces with hyperpigmentation significantly reduced skin pigmentation without abnormal reactions. Based on the results above, corn silk has good prospects for use as a material for suppressing skin pigmentation.

Anti-hepatoma activity and mechanism of corn silk polysaccharides in H22 tumor-bearing mice

Corn silk is a well known traditional Chinese herbal medicine and corn silk polysaccharides (CSP) possess multiple pharmacological activities. However, the antitumor effect of CSP on hepatocarcinoma has not been studied. This study aimed to investigate the effects of CSP on tumor growth and immune functions in H22 hepatocarcinoma tumor-bearing mice. The results demonstrated that CSP could not only inhibit the tumor growth, but also extended the survival time of H22 tumor-bearing mice. Besides, CSP administration could increase the body weight, peripheral white blood cells (WBC) count, thymus index and spleen index of H22 tumor-bearing mice. Furthermore, the production of serum cytokines in H22 tumor-bearing mice, such as IL-2, IL-6 and TNF-α, was enhanced by CSP treatment. In addition, no toxicological effects were observed on hepatic function and renal function in CSP-treated mice transplanted H22 tumor cells. In summary, this experimental finding indicated that CSP could elevate the immune functions in H22 tumor-bearing mice to enhance its antitumor activity and CSP seems to be a safe and effective agent for the treatment of hepatocellular carcinoma.

Enzymolysis-ultrasonic assisted extraction, chemical characteristics and bioactivities of polysaccharides from corn silk

An enzymolysis-ultrasonic assisted extraction (EUAE) procedure of corn silk polysaccharides (CSPS) was established and the physicochemical properties, antioxidant and anticancer activities of CSPS were studied. Orthogonal test and response surface methodology were applied to optimize the extraction parameters. The optimum enzymolysis and ultrasonic conditions were cellulase content of 7.5% for 150 min at 55 °C and liquid-solid ratio of 31.8 for 34.2 min at 66.3 °C, respectively. Under these conditions, the yield of CSPS increased from 4.56% to 7.10%. CSPS obtained by hot water and EUAE were composed of rhamnose, arabinose, xylose, mannose, galactose and glucose with molecular ratios of 4.17:17.33:5.59:18.65:19.11:35.14 and 8.83:15.77:7.92:12.39:11.15:43.94, respectively. Their molecular weight distributions were 10.52 × 10(4) and 6.88 × 10(4)Da, respectively. CSPS obtained by EUAE showed morphological and conformation changes and higher antioxidant and anticancer activities compared with CSPS extracted by hot water.

Anti-diabetic activity of Vaccinium bracteatum Thunb. leaves' polysaccharide in STZ-induced diabetic mice

Vaccinium bracteatum Thunb. (VBT) is a traditional Chinese herbal medicine. The anti-diabetic activity of VBT leaves' polysaccharide (VBTLP) is studied in this paper. The results indicated VBTLP had a dose-dependent decrease on the blood glucose (BG) level, and the time effect of VBTLP on BG level was also significant. The insulin level of high dose group (HDG) was significantly higher (p<0.05) than that of model control (MC) group. Compared to MC, HDG and lose dose group (LDG) had significantly lower (p<0.05) TC and LDL-C levels, however, TG and HDL-C levels are similar. Compared to non-diabetic control (NC), HDG and LDG had similar plasma lipid levels except for higher LDL-C level. Although body weights of LDG and HDG were significant lower (p<0.05) than that of NC from week 2 to week 6, they were similar to that of PC. The results indicate VBTLP possesses a potential hypoglycemic effect in streptozotocin-induced diabetic mice.

Corn silk (Stigma maydis) in healthcare: a phytochemical and pharmacological review

Corn silk (Stigma maydis) is an important herb used traditionally by the Chinese, and Native Americans to treat many diseases. It is also used as traditional medicine in many parts of the world such as Turkey, United States and France. Its potential antioxidant and healthcare applications as diuretic agent, in hyperglycemia reduction, as anti-depressant and anti-fatigue use have been claimed in several reports. Other uses of corn silk include teas and supplements to treat urinary related problems. The potential use is very much related to its properties and mechanism of action of its plant's bioactive constituents such as flavonoids and terpenoids. As such, this review will cover the research findings on the potential applications of corn silk in healthcare which include its phytochemical and pharmacological activities. In addition, the botanical description and its toxicological studies are also included.