Corn silk ‘cure’ for kidney failure

Can extract of corn silk provide the next best cure for kidney (renal) and liver failure, prostate cancer, hypertension, obesity, type 2 diabetes among other chronic diseases?

Researchers from the University of Akron, United States of America (USA) and Essraa Hospital, Jordan, have developed herbal nano mix for renal failure.

The herbal mix extract for treating kidney failure, according to a study published in the journal Bioequivalence & Bioavailability and titled “A natural nano formulation for renal failure cure,” is formed of a natural nano herbal mix, corn silk extract, black seed (Nigella sativa) extract, gum arabic and frozen-dried camel milk powder or extract of them. “In particular the formulation is given orally in capsules. Observed results showed excellent results for chronic renal failure (CRF) with no adverse or side effects,” the researchers noted.

Botanically called Stigma maydis, Corn silk (CS) is made from stigmas, the yellowish thread like strands from the female flower of maize. It is a waste material from corn cultivation and available in abundance. It has been consumed for a long time as a therapeutic remedy for various illnesses and is important as an alternative natural-based treatment. It has been used as traditional medicine in many parts of the world such as China, Turkey, United States and France. It is used for the treatment of cystitis, edema, kidney stones, diuretic, prostate disorder, and urinary infections as well as bedwetting and obesity. It soothes and relaxes the lining of the bladder and urinary tubules, hence reducing irritation and increasing urine secretion.

Other beneficial treatments of CS include anti-fatigue activity, anti-depressant activity and kaliuretic. In addition, it possesses excellent antioxidant capacity and demonstrated protective effects in radiation and nephrotoxicity.

However, a recent study showed that there is no antibacterial activity in CS when it was investigated against bacterial species such as Pseudomonas aeruginosa, Klebsiella pneumonia, Staphylococcus aureus, Streptococcus pneumonia, Escherichia coli and Streptococcus pyogenes. In China, it is considered very important medicinal plant in the treatment of prostate problems.

Meanwhile, the Native Americans used CS to treat urinary tract infections, malaria and heart problems. Although not scientifically proven, CS tea has been claimed to have many benefits to human health such as lowering blood pressure, decrease prostate inflammation, diabetic and urinary tract infection, edema, obesity and promote relaxation. To date, there are various CS commercial products for medicinal uses are available in the market.

CS is rich in phenolic compounds, particularly flavonoids. It also consists of proteins, vitamins, carbohydrates, calcium, potassium, magnesium and sodium salts, volatiles oils and steroids such as sitosterol and stigmasterol, alkaloids, and saponins. Due to its potential benefits, there are several studies reported the pharmacological activities of CS.

Meanwhile, several studies have shown that chronic kidney disease or kidney damage is caused by one of the following: diabetes, hypertension, kidney inflammation, polycystic kidney disease (PKD), obstruction of urinary tract cause of Benign prostatic hyperplasia (BPH), kidney stones or chemical drug poisoning.

BPH refers to enlargement of the prostate that is unrelated to cancer.

Until now, treatment of renal failure usually consists of either dialysis or kidney transplant when case becomes complicated and does not respond to dialysis.

The researchers wrote: “Till this moment no renal failure cure was found anywhere in the world. Our natural composition is the first cure of its kind to renal failure. Formulation used to treat renal failure is composed of the following ingredients, including, corn silk extract, black seed (Nigella sativa) extract, gum arabic and frozen-dried camel milk powder.

“In a recent study performed by Elin Yulinah Sukandar et al. in 2013, corn silk extract has been found to repair kidney functions using rat models. Blood tests showed both serum creatinine and urea, were improved. The extract was further revealed to reduce renal damage histologically.

“Zafar Ansari et al. conducted a new research on the effect of black seed (Nigella sativa) extract on renal functions on stage 3 and 4 of PKD patients. After 12 weeks of treatment, there was a progressive improvement in clinical features and biochemical parameters. There was a reduction in blood glucose, blood urea, serum creatinine, and 24-hour total urine protein. Moreover there was an increase in haemoglobin.

“Black seed was recommended by Prophet Mohammad (pbuh) 1400 years ago to cure all diseases except death.
“Khan, N; and Sultana, S found that black seed extract inhibited two stage renal carcinogenesis, and oxidative damage in Wistar rats.

“Adil Ali et al., studied effect of oral treatment of gum Arabic on 36 chronic renal failure (CRF) under regular haemodialysis for three months and found big improvement in renal functions. Biochemical parameters of creatinine, urea, and uric acid, decreased significantly up to 11.7 per cent, 44.18 per cent and 19.9 per cent respectively.

“Badreldin Ali et al., used gum Arabic on animal model of human Chronic Renal Failure, CRF (feeding adenine) for four weeks. Significant decrease of serum creatinine and urea showed a big promise of using gum Arabic for CRF.

“Agrawal RP et al. carried out a study to determine the efficacy of camel milk in controlling diabetic nephropathy. Twenty-four type-1 diabetic patients were randomly recruited from the outpatient diabetic clinic in PBM Hospital, Bikaner, India. Patients were given camel milk for six months. There was a significant improvement in the microalbuminuria after receiving camel milk for six months. A significant reduction in the mean dose of insulin for obtaining glycemic control was achieved. This may be due to good glycemic control or to the direct effect of camel milk.

“Nephrotoxicity is a major complication factor for cisplatin therapy. Cisplatin mediated nephrotoxicity is remarkably documented by reactive oxygen species. Camel’s milk has good nutritive value, antigenotoxic and anticytotoxic effects. Afifi M carried out a study using camel’s milk against side effects of Cisplatin on renal functions. He concluded the reno-protective potential of camel’s milk against cisplatin-induced oxidative stress and renal dysfunction in mice. Hence, camel’s milk has a potential to be used as therapeutic adjuvant in cisplatin nephrotoxicity.”

Another study published in the journal Frontiers of Chemistry demonstrated the anti-cancer activity of maize bioactive peptides.

The researchers from Agri-Foods Unit, Tecnologico de Monterrey, Monterrey, Mexico; Tecnologico de Monterrey, Escuela de Medicina, Monterrey, Mexico; and Maize Breeding Program-INIFAP Campo Experimental Bajío, Celaya, México noted: “Cancer is one of the main chronic degenerative diseases worldwide. In recent years, consumption of whole-grain cereals and their derivative food products has been associated with a reduced risk of various types of cancer. The main biomolecules in cereals include proteins, peptides, and amino acids, all of which are present in different quantities within the grain. Some of these peptides possess nutraceutical properties and exert biological effects that promote health and prevent cancer.

“In this review, we report the current status and advances in knowledge regarding the bioactive properties of maize peptides, such as antioxidant, antihypertensive, hepato-protective, and anti-tumor activities. We also highlight the potential biological mechanisms through which maize bioactive peptides exert anti-cancer activity. Finally, we analyse and emphasise the potential applications of maize peptides.”

They researchers concluded: “Evidence supports the use of maize peptides as therapeutic molecules against a broad array of diseases linked to oxidative damage, such as cancer. In vitro models have been useful to investigate the antihypertensive and anticancer effects of maize peptides. However, in addition to in vitro evidence, in vivo experiments and clinical trials are needed to demonstrate the physiological effects of peptides.

Few clinical trials have been conducted involving peptides and cancer. Some synthetised peptides derived from sea products are being tested in phase II trials, these include: BioPep, Plitidepsin, Elisidepsin, and Tasidotin. Even so this studies indicate that there is an enormous potential in the bioactivity of peptides derived from foods for the prevention and/or treatment of cancer. Also, there is an important opportunity for maize peptides with anticancer activity in diverse cancer cell lines as well as in different animal models that represent different carcinomas. In a future, the clinical efficacy will likely require intervention at several levels, and is necessary to test to evaluate their safety in short and long-term in vivo models and clinical trials on a large and heterogeneous populations.”

Also, a study published in the journal Life Sciences assessed the potential anti-cancer activity of maysin, a major flavonoid of corn silk, in androgen-independent human prostate cancer cells (PC-3).

The researchers found that Maysin dose-dependently reduced the PC-3 cell viability, with an 87 per cent reduction at 200 μg/ml. Maysin treatment significantly induced apoptotic cell death, Deoxy ribonucleic Acid (DNA)/genetic material fragmentation, depolarization of MMP, and reduction in Bcl-2 and pro-caspase-3 expression levels. Maysin also significantly attenuated phosphorylation of Akt and ERK. A combined treatment with maysin and other known anti-cancer agents, including 5-FU, etoposide, cisplatin, or camptothecin, synergistically enhanced PC-3 cell death.

These results suggested for the first time that maysin inhibits the PC-3 cancer cell growth via stimulation of mitochondria-dependent apoptotic cell death and may have a strong therapeutic potential for the treatment of either chemo-resistant or androgen-independent human prostate cancer.

Another study published in the journal Oxidative Medicine and Cellular Longevity examined corn silk induced apoptosis in human breast cancer (MCF-7) cells via the Reactive Oxygen Species (ROS)-mediated mitochondrial pathway.

The researchers from the Department of Pharmacognosy, College of Pharmacy, King Saud University, Riyadh, Saudi Arabia; Al-Jeraisy Chair for DNA Research, Zoology Department, College of Science, King Saud University, Saudi Arabia; and Zoology Department, College of Science, King Saud University, Riyadh, Saudi Arabia, noted: “Cancer has been recognized as one of the life-threating diseases. Breast cancer is a leading cause of mortality among women. In spite of current developments in the therapy and diagnosis of cancer, the survival rate is still less.

“Recently, plant-derived natural products gain attention as anticancer agents due to the nontoxic nature. Therefore, the aim of present study was to investigate the anticancer capacity of corn silk extract (CSE) on human breast cancer (MCF-7) and normal human mesenchymal (hMSC-TERT4) cells. Following 24 h treatment to corn silk extract, the cytotoxicity was assessed by MTT, NRU, and morphological assays. The oxidative stress markers (GSH and LPO), ROS production, MMP change, and expression of apoptotic marker genes (p53, Bax, Bcl-2, caspase-3, and caspase-9) were also studied in MCF-7 cells treated at 250 to 1000 μg/ml of CSE for 24 h.

“Our results showed that CSE decreased the cell viability and increased the apoptosis in a dose-dependent manner. The level of LPO and ROS production was found significantly higher; however, GSH and MMP level was observed lower in CSE-treated MCF-7 cells. The real-time PCR data showed a significant upregulation in p53, Bax, caspase-3, and caspase-9 and downregulation in the mRNA expression of Bcl-2 genes in MCF-7 cells exposed to CSE. Collectively, the data from this study stated that corn silk extract induced apoptosis via the ROS-mediated mitochondrial pathway in MCF-7 cells.”

Another study published in the journal Evidence-Based Complementary and Alternative Medicine and demonstrated how corn silk tea could be used to treat hypertension.

The Chinese researchers from Hospital of Chengdu University of Traditional Chinese Medicine, Chengdu, Sichuan Province 610072, China; Cardiovascular Diseases Center, Xiyuan Hospital, China Academy of Chinese Medical Sciences, Beijing 100091, China; and Cardiology Division, West China Hospital, Sichuan University, Chengdu, Sichuan Province 610041, China, noted:

“Corn silk, a traditional Chinese medicine, has been found to exert an antihypertensive effect in clinical practice and trials. However, systematic review of current evidence on this topic was not available. Thus, this study aims to assess safety and efficacy of corn silk tea (CST) in improving clinical outcomes in patients with hypertension.

“A systematic literature search was conducted through popular electronic databases up to October 2018. Randomized controlled trials (RCTs) comparing CST plus conventional antihypertensive drugs with conventional antihypertensive drugs alone were included. The main outcome was total blood pressure lowering efficacy. The risk of bias assessment according to the Cochrane Handbook was used to evaluate the methodological quality of the included trials. Review Manager 5.3 software was used for data analyses. Five RCTs involving 567 participants were included. Due to the poor quality of methodologies of most trials, limited evidence showed that CST plus antihypertensive drugs might be more effective in lowering blood pressure compared with antihypertensive drugs alone. However, there is no evidence that CST plus conventional antihypertensive drugs has less adverse events than conventional antihypertensive drugs.”

The researchers concluded: “In summary, CST plus antihypertensive drugs could be more effective on lowering blood pressure than conventional antihypertensive drugs alone, accordingly suggesting CST may be a new alternative natural-based treatment for hypertension, although some limitations might weaken the validity of positive findings considering the poor methodological design. From a clinical point of view, well-designed phytotherapy trials with high methodological quality are needed to validate the effect of CST for patients with hypertension.”