General features: It is a perennial climbing plant, native of India, Cambodia, Malaysia, Bangladesh, China and several other South East Asian nations. It can be found also in many of the Polynesian islands like Hawaii, Melanesia and Mascarenes. In English, it is commonly called Skunk vine or Stink vine for creating strong sulfurous odor if leaves or stems are crushed. The stem grows ~ 25 ft or more. Leaves opposite with petioles 2.5 in long. The leaf blades are oval to linear-laceolate ~ 4.5 in long and hairy, glaborous too often lobed at the base. The flowers are small grayish pink or lilac with petals of five which grow in clusters having the densely hairy corollas. The fruits are shiny brown ~ 2.5 in diameter. Flowers appear in October to January whereas the fruits grow during November to April. The plant is named Prasarini or Gandhali in Hindi and গ্যাঁদাল গাছ in Bengali. It belongs to the Rubiaceae family. The fetid odor originates from the bruised leaves is due to the oozing of sulfurous compounds largely di-methyl sulfide, (CH3)2S. The leaves are generally used for variety of medicinal reasons as a folk medicine chiefly to control common intestinal problems like jaundice, diarrhea or dysentery. It is also counted to be an invigorator of male sexual health. Not much works are performed regarding its physiological or biological actions. It is realized that there are plenty of antioxidant and anti-inflammatory components existing within this herb. Experiments on animal indicate that it can enhance the production of semen as well as help secrete testerone displaying aphrodisiac or erectile effects. So far no toxic report is ever cited against this herb. The leaves are usually extracted for a number of medicinal uses. Besides to prevent intestinal ailments, the leaf extract is further used to control rheumatoid arthritis or in case of any problematic labors. As per extra interest, the herb offers youthful radiance to men possibly by virtue of its aphrodisiac action. Histological studies indicate that it promotes seminal vesicle and epididymal health and also increases the blood flow in testes. This actions improve penile erection index to a significant extent as compared to any other marketed drugs.
Significant bioactive components: Approximately, 77 components have been isolated from this herb. The total phenolic ingredients in the leaves are ~ 62.64 ± 1.32 mg /g of Ferulic acid equivalent whereas for stems the value is ~ 60.93 ± 3.40. The major bioactive chemicals are, Ursolic acid, sterols (Stigmasterol, Campesterol and Sitosterol), Hentriacontane, Hentriacontanol, Iridoid glycosides, Flavonoids, Ceryl alcohol, Methyl mercaptan, Palmitic acid, Paederine, paederone, Paederolone, and Paederenine. Although some of the components have been exactly identified but still many of them remain to be identified, like the flavonoids. The plant is enriched with phenolic ingredients but the exact nature is undetected. The reasonable explanation behind its anti-inflammatory action could be due to large flavonoid reserve. Followings are the major bioactive ingredients and their respective biological actions.
Ursolic acid, a pentacyclic tri-terpenoid has multiple beneficial action on health: 1) Inhibits cancer cell proliferation by inhibiting STAT3 activation pathway also induces apoptosis; 2) Decreases obesity; 3) Induces eryptosis; 4) Reduces muscle atrophy and stimulate its growth; 5) Helps improve cognitive function; 6) Helps regeneration of liver cells; 7) Enhances β – cell function for diabetic patients.
Stigmasterol is a precursor of Progesterone which is a valuable hormone playing many important physiological role related to Estrogen effects. It is also used during biosynthesis of Androgen, Corticoids and Vitamin D3. It helps preventing prostate, breast, ovarian and colon cancers. Like other phytosterols it inhibits cholesterol absorption and reduces the serum cholesterol level. It also has strong anti-oxidant, hypoglycemic and thyroid inhibiting role.
Campesterol has potent anti-inflammatory effect and works particularly well for osteoarthritis patients. It also has the lowering effect on cholesterol and LDL level in serum. It is a precursor of anabolic steroid Boldenone.
β – Sitosterol it is very effective in reducing Benign Prostate Hyperplasia and also able to reduce cholesterol and LDL level in serum.
Hentriacontane [(CH3) – (CH2)29 – (CH3)], alkane hydrocarbon which can be found in some other plants including bees wax. It has strong non-proliferating role on gastric cancer.
Iridoid glycosides – Aucubin is one of them cited as an example found in many plants of Rubiaceae family.
Iridoid glycosides are actually the secondary metabolites in many plants especially belonging to the Apocynaceae, Lamiaceae, Rubiaceae families. The iridoids exhibit wide range of medicinal effects like cardiovascular, anti-inflammatory, hepatoprotection, hypoglycemic, antimutagenic, antispasmodic, anti-tumor, antiviral, immunomodulatory and laxative. Iridoids are monoterpenes synthesized within those plants acting as a defensive agent against pests and diseases. It is seen to act preventing the progression of Alzheimer’s disorders. The mechanism of their actions are noticed to be through the blocking of various pro-inflammatory cytokines.
The exact role of Methyl mercaptan and Ceryl alcohol are not yet identified. It is possible that CH3SH or its oxidation product (CH3)2S could act as intermediate for further chemical reactions due to its nucleophile nature. It can act as a powerful anti-oxidant.
Pederin / Paederine – or any of its analogs could be identified in some cases of beetles’ larva. A majority of them have almost the similar structure and are identified in this herb. The compound has potent anticancer effect. The compound Pederin is tried as anticancer drug. It blocks mitosis even at extreme low doses (1 ng / ml) by inhibiting DNA without preventing the RNA synthesis. It is used for the treatment of several cancers or solid tumors.
Pharmacological actions: A great many number of pharmacological experiments are conducted assuring the beneficial role of this herb. Several of them are cited below.
Antidiarrheal effect – Experiments on animal legitimizes the fact that ethanolic extract of Paederia foetida can efficiently prevent diarrhea when used doses of 100 – 500 mg / Kg. Further experiments also revealed that this anti-diarrheal action occurs due to the inhibition of intestinal motility.
Aphrodisiac effect – Experiments using sexually mature male rats have confirmed significant level of increase in mounting frequency with simultaneous decrease of mounting latency, paired with tremendous enhancement of intromission frequency and decrease of intromission latency. These effects are dose-dependent and the peak value is achieved after 28 days of using 200 mg / Kg of ethanolic extract. It is very comparable to the active control of 0.5 mg / Kg of testerone injections biweekly. The effect could be due to the rise of testerone.
Effect on testerone level – The increase of serum testerone level is noticed when applied to the normal healthy rats (100 – 200 mg /Kg) for 28 days. The level rises to 4.0 – 5.0 ng / ml compared to the control which is 1.8 – 2.0 ng / ml. The rise can only be visualized after at least 15 days among the groups getting the highest doses.
Effect on testes, Penis and Prostate – The administration of ethanolic extract (50 – 200 mg / Kg) for 28 days increases the weight of testes (~ 6.0 %), epididymis (~ 10 %) and seminal vesicles (~ 8.0 %). The histological examination indicates a potent vasodilatory effect along with increased spermatid levels within testes with simultaneous enlargement of Sertoli cells. Similar studies also indicate an increase of penile erection index (~ 200 %) after 15 days of administration whereas after 28 days the increment is ~ 300 %. Both outperform the testerone control (0.5 mg / Kg) biweekly. No significant enhancement regarding the sizes of prostate have been reported.
Anti-oxidant effect – The fresh leaf extract shows potent antioxidative effect during in vitro assays which is much greater than quercitin but less than Vitamin E. In course of free radical scavenging test it also stays higher than quercitin but slightly lesser than Vitamin C.
Anti-inflammatory effect – The herb has strong anti-inflammatory effect which is proven by granuloma formation test in the test mice. It shows higher potency than the phenyl butazone.
Miscellaneous effects – The following effects are conducted in human subjects.
- Thrombolytic action is significant although somewhat less than the Streptokinase.
- Cytotoxic action is also very noteworthy but much less than the vincristine.
- The dose dependent decrease of blood glucose level have been observed which is almost comparable to Metformin.