Herbal teas based on plant extracts for natural well-being
The beneficial effects of oleuropein Oleuropein is the main polyphenol present in the leaves and fruits of the olive tree; it is found in extra virgin olive oil both in the form linked to a glucose molecule (glycated) and in the non-glycated form. For some time, natural polyphenols have attracted growing interest for their beneficial properties against numerous diseases, ranging from cancer to cardiovascular diseases, diabetes, neurodegenerative diseases and, more generally, for their ability to counteract the aging of cells, tissues and the whole organism. These properties are not limited to their known antioxidant power but go far beyond; the most recent studies have begun to demonstrate the effective clinical efficacy of the administration of polyphenols on humans and to reveal the molecular and cellular mechanisms with which these substances exert these effects and which are the basis of the nutritional virtues commonly associated with the so-called “Mediterranean Diet ”.
The results of the clinical trials conducted, together with the available epidemiological and experimental data consistently support the protective effect associated with the daily intake of oleuropein through the use of nutraceutical preparations consisting of olive leaf extracts enriched with the substance.
The data provided by scientific research are particularly significant as regards the anti-neurodegenerative and anti-diabetic effects of oleuropein. The former were reported thanks to a series of studies carried out both on neuronal cells in culture and on model animals, in particular genetically modified mice in order to mimic a brain situation similar to that present in Alzheimer’s disease, the main form of dementia associated to aging in humans. In these mice, the administration of oleuropein with the normal meal in doses equivalent to approximately 200-°©-300 mg in humans has clearly beneficial effects in terms of cognitive performance, which are maintained at levels comparable with those of normal mice of the same age . At the histopathological and cellular level, this effect can be traced back to the reduction of the load of amyloid plaques (which characterize the disease) and of the inflammatory response and, in parallel, to a strong stimulation of the autophagic response, which protects the cell against the toxicity of the plaques and stimulates its reabsorption. These effects, which show a clear dose-°©-dependence, are similar to those produced by other polyphenols (resveratrol, curcumin, epigallocatechins) and can, at least in part, be traced back to the mobilization of calcium from intracellular deposits with the consequent activation of signals that result in the activation of autophagy. It has also been demonstrated that oleuropein can directly reduce the load of amyloid plaques by favoring a pathway that reduces the production of the precursor peptide of the same. Furthermore, recent studies on other polyphenols demonstrate effects of an epigenetic type, consisting in the modulation of the expression of particular sets of genes following reversible chemical modifications of the chromatin which do not alter the genetic heritage but the way in which it is expressed. These studies explain the anticancer effects of these polyphenols and, presumably, also those exerted by oleuropein, through the regulation of the activity of enzymes involved in the chemical modifications of chromatin.
The antidiabetic action of oleuropein is supported by recent clinical trials. One of these showed that the daily administration of about 50 mg of the polyphenol for 12 weeks to a group of middle-aged, overweight subjects at risk for developing type 2 diabetes reduced blood sugar and improved both the secretion and insulin sensitivity. Another study conducted in human subjects with type 2 diabetes given 500 mg of oleuropein per day for 14 weeks showed a significant improvement in glucose homeostasis, with reductions in glycosylated hemoglobin and fasting insulin levels, while a reduction in starch digestion and absorption was noted in rats treated with oleuropein. Other studies have shown that in vitro oleuropein prevents the amyloid aggregation of amylin, a peptide secreted together with insulin by pancreatic beta cells, the aggregates of which are believed to be co-responsible for the cellular suffering that accompanies the onset of diabetes type 2. The efficacy of oleuropein in contrasting both the onset of type 2 diabetes and some of its consequences can be seen in a broader protective effect against the metabolic syndrome. In fact, other studies have shown that in mice, oleuropein attenuates fatty liver disease and reduces obesity induced by a high-fat diet. The anti-°©-obesity effect and the modulation of glucose homeostasis had previously been reported also for other plant polyphenols. In conclusion, the available scientific data convincingly support the efficacy of the daily intake of large doses of oleuropein for the prevention of pathologies linked to aging such as senile dementia and cancer, or to metabolic disorders such as type 2 diabetes and the metabolic syndrome. The constant daily intake of large doses of oleuropein through the supplementation, with nutraceutical products, of the normal content of the substance in the diet therefore appears useful and recommendable in order to prevent and treat the metabolic syndrome and type 2 diabetes mellitus, also in consideration of the absence of side effects related to the intake of oleuropein.
Bacopa monnieri is a nootropic herb that has been used for longevity and cognitive enhancement. Supplementation with its extracts can improve memory, especially in the short term, and bring benefits for mental health. Bacopa monnieri, commonly known as water hyssop, is an herb often used in Ayurvedic medicine. It is taken in various formats with the aim of improving cognitive functions, relieving stress and promoting an overall improvement in vitality. Bacosides, the main active substances of Bacopa monnieri, interact with the dopamine and serotonin systems, but the main mechanism concerns neuronal communication, stimulating the growth of neuronal dendrites. Bacopa monnieri also has antioxidant effects.
The benefits of Bacopa monnieri
An improvement in memory is the main known effect of Bacopa. Although effects of this nature are usually studied in the elderly, Bacopa monnieri appears to be effective in young people as well. Some preliminary research suggests it may reduce cortisol secretion and depletion of dopamine and serotonin during chronic stress. It may have antidepressant effects, but more confirmatory research is needed.
Side effects of Bacopa monnieri
Taking Bacopa monnieri on an empty stomach can cause nausea, cramping, bloating and diarrhea. Since Bacopa monnieri can have anxiolytic (anxiety reducing) effects, it is not advisable to take it in combination with other anxiolytics.
Pumpkin seeds (Cucurbita maxima) have been used in ethnic and traditional medicine as a remedy for kidney, bladder and prostate disorders. Pumpkin seed oil has several phenolic compounds such as vanillic acid, vanillin, luteolin and sinapic acid . Pumpkin seed consumption reduces markers of inflammation, increases lymphocyte count, improves phagocytic activity, and inhibits the progression of fatty liver disease into steatohepatitis.
Recent studies have shown how oral intake of Cucurbita extract reduces patients’ bladder hyperactivity, preventing urinary disorders and producing an effect on urinary health; it also reduces the risk of bladder and kidney stones.
The lipid extract of Cucurbita maxima seeds slows the progress of hypertension and decreases hypercholesterolemia due to the content of unsaturated fatty acids and phytosterols. Furthermore, Cucurbita seed extracts show hypoglycaemic activity, contributing to the prevention of diabetes mellitus.
Epilobium angustifolium L. is a well-known medicinal plant traditionally used in the treatment of urogenital diseases, stomach and liver disorders, skin problems, etc. E. angustifolium extracts exhibit antiproliferative, cytotoxic, antioxidant, anti-inflammatory, immunomodulatory and antimicrobial activities. The unique combination of biological properties demonstrated by the results of some studies indicates that its extracts exert a positive effect in benign prostatic hyperplasia (BPH) and potentially in the prevention of prostate cancer.
The efficacy of phytotherapy with E. angustifolium is still poorly tested in clinical trials, while numerous beneficial effects of the extracts on prostate function have been documented in in vitro and in vivo tests.
The use of Silybum marianum for therapeutic purposes of this plant has been known since ancient times. Silymarin is extracted from the pericarp of milk thistle fruits, a mixture of flavonolignans known for their purifying and protective properties on the liver.
Milk thistle is traditionally used in acute or chronic liver disease. Research indicates that this extract is able to perform a regenerative action on the liver cell and counteract the effects of hepatotoxic agents. Furthermore, it is an effective antioxidant.
Efficacy of lifestyle changes in subjects with non-alcoholic liver steatosis and metabolic syndrome may be improved with an antioxidant nutraceutical: a controlled clinical study. Drugs R. D. 2015 Mar;15(1):21-5.
Hepatoprotective herbal drug, silymarin from experimental pharmacology to clinical medicine. Indian J Med Res. 2006 Nov;124(5):491-504.
Silymarin as Supportive Treatment in Liver Diseases: A Narrative Review Adv Ther. 2020; 37(4): 1279–1301.
Taraxacum officinale, also known as dandelion, is a vegetable that has limited traditional use in East Asian countries. It is used worldwide for its diuretic effect.
Animal studies and in vitro tests indicate that dandelion extract exerts beneficial effects on human health, although more research is needed to attribute these effects to the individual active ingredients
Research in rodents suggests that dandelion may facilitate digestion by increasing the transit of food between the stomach and small intestine. Dandelion root extract may also exert a protective effect on the pancreas and exhibit antiallergenic properties.
Recent studies indicate efficacy of dandelion extracts in conferring protective effects in the liver in mouse models of ethyl alcohol, CCl4 and acetominophen hepatotoxicity secondary to its antioxidant properties, since these toxic substances exert hepatotoxicity by oxidative mechanisms. Feeding dandelion extract to mice with a high-fat diet attenuates fatty liver production and liver inflammation, and subsequent insulin resistance, through modulation of AMP-dependent protein kinase (AMPK) in liver tissue.
According to other studies, oral ingestion of dandelion appears to confer some protective effects on the liver of rodents; the mechanism seems to be due to the antioxidant properties of the dandelion extract.
Mahesh A1, et al. Hepatocurative potential of sesquiterpene lactones of Taraxacum officinale on carbon tetrachloride induced liver toxicity in mice. Acta Biol Hung. (2010)
Davaatseren M1, et al. Taraxacum official (dandelion) leaf extract relieves high-fat diet-induced nonalcoholic fatty liver. Food Chem Toxicol. (2013)
Colle D1, et al. Antioxidant properties of Taraxacum officinale leaf extract are involved in the protective effect against hepatoxicity induced by acetaminophen in mice. J Med Food. (2012)
González-Castejón M1, et al. Reduction of adipogenesis and lipid accumulation by Taraxacum officinale (Dandelion) extracts in 3T3L1 adipocytes: an in vitro study. Phytother Res. (2014)
Curcumin – a yellow pigment found mainly in turmeric (Curcuma longa, Turmerinc English, a flowering plant of the ginger family better known as a spice used in curry) quantity of antioxidants produced by the body.
Curcumin and curcuminoids present in turmeric can be extracted to produce supplements with higher potency than turmeric. However, curcumin is poorly absorbed during digestion, so different formulations have been created to improve its bioavailability.
Main benefits of curcumin
Curcumin supplementation reliably reduces inflammation markers and increases the levels of endogenous antioxidants in the body. Available research supports small to moderate improvements in symptoms of depression and anxiety and in pain and function in osteoarthritis. Research also indicates its effectiveness in reducing LDL cholesterol, blood sugar and blood pressure as well.
Main disadvantages of curcumin
One of the major disadvantages of curcumin is that it is poorly absorbed when orally ingested on its own. As for potential adverse effects, doses of up to 8 grams of curcuminoids have not been associated with serious adverse effects in humans. However, longer-term studies that are more comprehensive in their assessments are needed. Studies using high doses of curcumin have reported some mild adverse effects, including nausea, diarrhea, headache, skin rashes.
How does curcumin work?
The potential beneficial effects of curcumin appear to be primarily a result of its anti-inflammatory and antioxidant properties. These properties are mediated by the direct or indirect interaction of curcumin with various molecular targets, including transcription factors, enzymes, cell cycle proteins, receptors, cell surface adhesion molecule, growth factors, and protein kinases.