In Hinduism, the Lotus flower is said to be the centre of the universe. The legend says that it bloomed from the navel of God Vishnu and at the centre of the flower sat Brahma, the creator of the world.
INTRODUCTION
Alternative names: Indian lotus, sacred lotus, bean of India, or simply lotus.
Nelumbo Nucifera is an acquatic plant native to eastern Asia. It is distributed from the Caspian Sea and Iran through India, China, Vietnam to Japan, Malaysia, New Guinea and Australia. Lotus grows in flood plains of rivers, in ponds, lakes, pools in marshes and swamps, and backwaters of reservoirs.
Many parts of the plant are used: seeds and tubers are edible, and widely used in many Asian cuisines.
Young leaves, leaf stalks and flowers are consumed as vegetables.
Flowers are also used in the production of perfume, and several parts of the plant are used medicinally.
The plant is also of great interest to nanothecnology because of the self-cleansing property of its leaves.
Even after emerging from mud, the leaves do not retain dirt when they unfold.
This mechanism has been studied intensively and it’s known as “lotus effect”.
CLASSIFICATION
Kingdom: Plantae
Subkingdom: Tracheobionta
Superdivision: Spermatophyta
Division: Magnoliophyta
Class: Magnoliopsida
Subclass: Magnoliidae
Order: Proteales
Family: Nelumbonaceae
Genus: Nelumbo Adans
Species: nucifera
PHYTOCHEMICAL CONSTITUENTS
Phytochemical investigation of the extract of the leaves of Nelumbo Nucifera results in the
isolation of 22 components.The main are:
- five norsesquiterpenes
- four flavonoids, among which quercetin
- two triterpenes
- two alkaloids: nuciferine and neferine
Quercetine
Scientific name:3,3',4',5,7-pentahydroxyflavone
Quercetin is a polyphenolic flavonoid.
Good sources include apples, onions, berries, teas, red wines, and many other foods.
People use quercetin as a medicine.
Quercetin appears to have anti-inflammatory and antioxidant properties.
It has been promoted as being effective against a wide variety of diseases, including cancer. Quercetin is used for treating conditions of the heart and blood vessels including atherosclerosis, high cholesterol, heart disease, and circulation problems.
It is also used for diabetes, cataracts, hay fever, peptic ulcer, schizophrenia, inflammation, asthma, gout, viral infections, chronic fatigue syndrome (CFS), preventing cancer, and for treating chronic infections of the prostate.
Quercetin is also used to increase endurance and improve athletic performance.
Nuciferine
Nuciferine is an alkaloid found within the plants Nymphaea caerulea and Nelumbo nucifera.
The observations made in a psychopharmacological study confirm that nuciferine has a chlorpromazine-like neuroleptic activity. Nuciferine shows a pharmacologic profile of action associated with dopamine-receptor blockade. The main behavioural effects produced by the drug include: catalepsy, hypnosis, morphine analgesia and anticonvulsant action. Nuciferine also seems to inhibit the amphetamine toxicity.
Psychopharmacological studies on nuciferine,1978
The other molecular mechanisms are explained below.
Neferine
Neferine is a bis-benzylisoquinoline alkaloid isolated from the green seed embryos Nelumbo Nucifera Gaertn (Lotus) that displays multiple pharmacological activities including anti-tumor, antidepressant-like and antiarrhythmic actions.
Neferine exerts its antithrombotic effect by inhibiting platelet aggregation and promoting dissociation of platelet aggregates, 2013
TRADITIONAL USES
The Sacred lotus has been used in the Orient as a medicinal herb for well over 1,500 years. It seems to have many therapeutic effects such as astringent, cardiotonic, febrifuge, hypotensive, resolvent, stomachic, styptic, tonic and vasodilator. We can mention some examples:
- The leaf juice is used in the treatment of diarrhoea.
- The flowers are used in the treatment of premature ejaculation and recommended as a cardiac tonic and a decoction of the floral receptacle is used in the treatment of abdominal cramps and bloody discharges
- The flower stalk is haemostatic so it is used in treating bleeding gastric ulcers, excessive menstruation, post-partum haemorrhage.
- The stamens and the roots are used in treating urinary frequency, premature ejaculation, haemolysis, epistasis,uterine bleeding, hemoptysis.
- A decoction of the fruit is used in the treatment of agitation, fever and heart complaints.
MOLECULAR MECHANISM
Recent studies have pointed out many pathological conditions in which Nelumbo Nucifera extract may act as a protecting factor.
Anti-diabetic effect
In 2012, Nguyen’s group found that Nuciferine, extracted from Nelumbo nucifera, stimulated both phases of insulin secretion in isolated islets.
In the first phase of insulin secretion glucose enters the β-cells through the glucose transporter, GLUT2.Glucose goes into glycolysis and the respiratory cycle, where multiple, high-energy ATP molecules are produced by oxidation, leading to a rise in the ATP:ADP ratio within the cell.An increased intracellular ATP:ADP ratio closes the ATP-sensitive SUR1/Kir6.2 potassium channel. This prevents potassium ions (K+) from leaving the cell by facilitated diffusion, leading to a build up of potassium ions. As a result, the inside of the cell becomes more positive with respect to the outside, leading to the depolarisation of the cell surface membrane.On depolarisation, voltage-gated calcium ion (Ca2+) channels open which allows calcium ions to move into the cells by facilitated diffusion.An increased intracellular calcium ion concentration causes the activation of phospholipase C, which cleaves the membrane phospholipid phosphatidyl inositol 4,5-bisphosphate into inositol 1,4,5-trisphosphate and diacylglycerol.Inositol 1,4,5-trisphosphate (IP3) binds to receptor proteins in the plasma membrane of the endoplasmic reticulum (ER). This allows the release of Ca2+ ions from the ER via IP3-gated channels, and further raises the intracellular concentration of calcium ions.Significantly increased amounts of calcium ions in the cells causes the release of previously synthesized insulin, which has been stored in secretory vesicles.
Then the second phase of insulin secretion involves additional steps of insulin biosynthesis, packaging into granules and transport to the plasma membrane for release.
How does Nuciferine act? It's known that insulin release occurs with the depolarization of beta-cell. In presence of glucose, the increased levels of ATP cause the closing of ATP-sensitive potassium channels and the cell depolarizes. Nuciferine was found to stimulate insulin secretion by closing potassium-adenosine triphosphate channels, explaining anti-diabetic effects of Nelumbo nucifera. The results demonstrated that nuciferine, compared with glibenclamide, had a stronger effect on insulin secretion.
Nuciferine stimulates insulin secretion from beta cells-an in vitro comparison with glibenclamide,2012
In another study a newly isolated lotus plumule polysaccharide (LPPS) was administred to non-obese diabetic (NOD) female mice for 15 weeks and it showed a protective effect on type 1 diabetes. Infact it increased pancreatic cell numbers. Lotus (Nelumbo nucifera Gaertn) plumule polysaccharide ameliorates pancreatic islets loss and serum lipid profiles in non-obese diabetic mice,2013
Anti-obesity and hypolipidaemic effects
The leaf of Nelumbo nucifera has been used for summer heat syndrome as home remedy in Japan and China, and it has recently been used to treat obesity in China. In 2013, in Korea were examined the effects of Nelumbo Nucifera seed ethanol extrac (NSEE) in vivo and in vitro. Human pre-adipocytes were treated with NSEE, rats were fed with a normal diet and a high-fat diet with or without NSEE, respectively. In vitro treatment with NSEE resulted in inhibition of lipid accumulation and up-regulated lipid metabolism. It was also found a decreased expression of peroxisome proliferator-activated receptor gamma (PPARγ), glucose transporter 4 (GLUT4), and leptin in cultured human adipocytes, indicating that NSEE inhibited the differentiation of pre-adipocytes into adipocytes
Anti-obesity and hypolipidaemic effects of Nelumbo nucifera seed ethanol extract in human pre-adipocytes and rats fed a high-fat diet,2013
Inhibition of pancreatic lipase, alfa-glucosidase, alfa-amylase
In recent tests of a Chinese group of research a single dose of Nelumbo Nucifera leaf flavonoids (NLF) was administered by oral gavage in mices for acute toxicity. The observation of mices revealed that the NLF in vitro have an high inhibitory activity against porcine pancreatic lipase, α-amylase, and α-glucosidase. These properties result in lowered levels of: total cholesterol, triglycerides, low-density lipoprotein cholesterol, and malondialdehyde. The results demonstrate that NLFs can effectively ameliorate hyperlipidemia and inhibit the key enzymes related to type 2 diabetes mellitus.
Anti-obesity effect of Nelumbo nucifera leaves extract in mice and rats
The effects on alfa-amylase (A) and on lipase (B)
Antithrombotic effect
The work of Zhou YJ and his team showed that neferine acts on platelets. Washed mice platelets and mice platelet-rich-plasma (PRP) were used to investigate the effects of neferine on platelet aggregation, secretion and dissociation of agonist-formed platelet aggregates. The alkaloid treatment remarkably prevents thrombus formation by inhibiting all these events. In particular neferine inhibited collagen- and thrombin-induced platelet aggregation in mice, or ADP-induced platelet aggregation in PRP. The result of this study suggested that neferine of Lotus can significantly reduce the area of mice platelets adhesion to the collagen and inhibit thrombosis in vitro, such as vey antithrombotic drug. Neferine exerts its antithrombotic effect by inhibiting platelet aggregation and promoting dissociation of platelet aggregates,2013
Antioxidant effect
According to another study done in 2012, the lotus germ oil shows protective effects on liver and kidney too. Liu’s group treated mices orally with lotus germ oil or dl-α-tocopherol after administration CCl(4) for 49 consecutive days. Then it was found that the activities of SOD, CAT, and the concentration of GSH were increased significantly (p<0.05-0.01) after this treatment. Whereas, the content of the peroxidation product MDA were decreased significantly (p<0.05), similar to the serum levels of hepatic enzyme biomarkers . For this reason sacred Lotus requires to be considered a powerful antioxidant agent. Protective effects of lotus (Nelumbo nucifera Gaertn) germ oil against carbon tetrachloride-induced injury in mice and cultured PC-12 cells,2012
Antypiretic activity
Antipyretic activity of methanolic extract of stalks of N. nucifera was studied in rats with yeast induced pyrexia. After the administration of the extract in doses of 200 and 400 mg/kg rats had a significant dose dependent lowering of their body temperature. According to the results, the effect produced was comparable with the standard antipyretic drug, paracetamol (150 mg/kg). Evaluation of antipyretic potential of Nelumbo nucifera stalk extract,2000
Antitumor activity
The results of another interesting study suggest that neferine exhibited cytotoxicity against hepatocellular carcinoma cells called Hep3B cells, but not against HCC Sk-Hep1 and THLE-3, a normal human liver cell line. At first in this work a downregulation of c-Myc, cyclin D1, D3, CDK4, E2F-1, as well as dephosphorlyation of cdc2 by western blot analysis, as evidenced by the appearance of cell cycle arrest, were observed in Hep3B cells treated with neferine. Anothere evidence is that neferine induced ER stress and apoptosis, acting through multiple signaling cascades by the activation of Bim, Bid, Bax, Bak, Puma, caspases-3, -6, -7, -8 and PARP, and the protein expression levels of Bip, calnexin, PDI, calpain-2 and caspase-12 were also upregulated dramatically by neferine treatment. Nelumbo nucifera may be considered for its proapoptotic effect. Neferine isolated from Nelumbo nucifera enhances anti-cancer activities in Hep3B cells: Molecular mechanisms of cell cycle arrest, ER stress induced apoptosis and anti-angiogenic response,2013
TOXICITY
Neferine from Nelumbo nucifera may increase the risk of bleeding when taken with anthitrombotic drugs. Some examples include aspirin, anticoagulants such as warfarin, or heparin. Moreover, because of anti-diabetic activity of the plant, patients taking drugs for diabetes by mouth or insulin may be careful.
There are no adverse effects for nuciferine described in the literature. For quercetin, there are no adverse effects regarding the oral administration, while if it is injected intravenously, it could cause nausea, vomiting, excessive sweating, and shortness of breath.
Acute and subchronic oral toxicity studies of Nelumbo nucifera stamens extract in rats,2011
