Parsley (Petroselinum crispum) and Swelling / fluid retention: evidence and sources

Petroselinum crispum (Mill.) Fuss (parsley) is a popular medicinal plant widely used in different traditional medicines all over the world. This paper provides an updated review on the traditional use, phytochemistry, and pharmacological activities of parsley. Parsley contains volatile compounds such as terpenes and terpenoids in the essential oil, as well as phenolic compounds in the plant extract. Parsley is traditionally used as a diuretic, liver and stomach tonic, and for urolithiasis and indigestion. Pharmacological investigations also confirm several biological activities of parsley including hepatoprotective, nephroprotective, antiurolithiatic, neuroprotective, cardioprotective, and antineoplastic effects in animal and cell-based studies. Parsley has currently demonstrated several pharmacological activities in preclinical studies; however, there is a big lack in clinical evidence. Considering parsley as a possible valuable medicinal food, future clinical trials are recommended to evaluate the clinical efficacy and safety of the plant in different health conditions.

WHO estimates, around 80% of the especially developing world is indigent on complementary and alternative medicines which are prodigiously derived from herbal material. Parsley (Petroselinum crispum) is an important culinary herb originated from the Mediterranean region. It possesses small and dark seeds with volatile oil content. Petroselinum crispum is now planted throughout the world due to its usage in food industry, perfume manufacturing, soaps, and creams. Its main constituents subsume coumarins, furanocoumarins (bergapten, imperatori), ascorbic acid, carotenoids, flavonoids, apiole, various terpenoic compounds, phenyl propanoids, phathalides, and tocopherol. Due to these constituents, it has been annunciated to possess a number of possible medicinal emblematics including, antimicrobial, antianemic, menorrhagic, anticoagulant, antihyperlipidemic, antihepatotoxic, antihypertensive, diuretic effects, hypoglycaemic, hypouricemic, anti oxidative and estrogenic activities. In Morocco, Parsley is mostly used as an elixir to treat arterial hypertension, diabetes, cardiac and renal diseases. Antioxidant and antibacterial activities of parsley, made it propitious in food systems. Its ELI17 gene has been corroborated as a particularly fast-responding gene. There is a requisite for extensive research to avail the maximal benefits of this significant medicinal plant. The aim of this review paper is to divulge the chemical constituents of parsley that are explicitly related to substantial medicinal facets.

This work provides substantial evidence for the advocated diuretic effect of parsley in folk medicine and determines the mechanism of action of the herb. Rats offered an aqueous parsley seed extract to drink, eliminated a significantly larger volume of urine per 24 h as compared to when they were drinking water. These findings were supported by the results of other experiments using an in situ kidney perfusion technique which demonstrated also a significant increase in urine flow rate with parsley seed extract. This effect was still apparent in presence of amiloride, furosemide and in the absence of sodium, but not in the absence of potassium, suggesting that the diuretic effect of the herb is mediated through an increase in K+ retention in the lumen. Parsley extract, was shown on the other hand, to reduce the activity of the Na+-K+ ATPase in both cortex and medulla homogenates. Such an inhibition would decrease apical cellular Na+ reabsorption, lower K+ secretion, increase K+ concentration in the intercellular space and consequently would inhibit passive K+ influx across the tight junctions. The mechanism of action of parsley seems to be mediated through an inhibition of the Na+-K+ pump that would lead to a reduction in Na+ and K+ reabsorption leading thus to an osmotic water flow into the lumen, and diuresis.