Palmatine is a protoberberine

alkaloid Alkaloids are a class of basic, naturally occurring organic compounds that contain at least one nitrogen atom. This group also includes some related compounds with neutral and even weakly acidic properties. Some synthetic compounds of similar ...

found in several plants including ''

Phellodendron amurense ''Phellodendron amurense'' is a species of tree in the family Rutaceae, commonly called the Amur cork tree. It is a major source of '' huáng bò'' ( or 黄檗), one of the 50 fundamental herbs used in traditional Chinese medicine. The Ainu pe ...

'', ''

Coptis Chinensis ''Coptis chinensis'', the Chinese goldthread, is a species of goldthread flowering plant native to China. Etymology *''Coptis chinensis'' Franch. var. ''chinensis''

'' (Rhizoma coptidis, chinese goldthread) and '' Corydalis yanhusuo'', ''

Tinospora cordifolia ''Tinospora cordifolia'' (common names gurjo, heart-leaved moonseed, guduchi or giloy) is a herbaceous vine of the family Menispermaceae indigenous to tropical regions of the Indian subcontinent. It has been used in Ayurveda to treat various di ...

'' (gurjo, heart-leaved moonseed), ''

Tinospora sagittata ''Tinospora'' is a genus of succulent woody climbing shrubs. Thirty-four species are currently recognized. Species generally send down long aerial roots from host trees. They have corky or papery bark. They are found in tropical and sub-tropical ...

'', ''

'' (amur cork tree), '' Stephania yunnanensis.'' It is the major component of the protoberberine extract from ''

Enantia chlorantha ''Enantia'' is a genus of butterflies in the subfamily Dismorphiinae. They are native to the Americas The Americas, which are sometimes collectively called America, are a landmass comprising the totality of North and South America. The ...

''. It has been studied for its potential use in the treatment of jaundice,

dysentery Dysentery (UK pronunciation: , US: ), historically known as the bloody flux, is a type of gastroenteritis that results in bloody diarrhea. Other symptoms may include fever, abdominal pain, and a feeling of incomplete defecation. Complications ...

, hypertension,

inflammation Inflammation (from la, inflammatio) is part of the complex biological response of body tissues to harmful stimuli, such as pathogens, damaged cells, or irritants, and is a protective response involving immune cells, blood vessels, and molec ...

, and liver-related diseases. This compound also has weak ''

in vitro ''In vitro'' (meaning in glass, or ''in the glass'') studies are performed with microorganisms, cells, or biological molecules outside their normal biological context. Colloquially called " test-tube experiments", these studies in biology ...

'' activity against

flavivirus ''Flavivirus'' is a genus of positive-strand RNA viruses in the family ''Flaviviridae''. The genus includes the West Nile virus, dengue virus, tick-borne encephalitis virus, yellow fever virus, Zika virus and several other viruses which may cau ...

Pharmacology

Neuroprotective activity

Palmatine can be used to treat Alzheimer’s disease, mainly by inhibiting the activity of acetylcholinesterase (AChE), butyrylcholinesterase (BChE) and neuraminidase-1 (NA-1). It was found, that the positively charged nitrogen on palmatine binds in the gorge of active sire of AChE. Research show that palmatine had antidepressant effect. It was achieved by regulating brain catalase levels, monoamine oxidase-A (MAO-A) activity, lipid peroxidation, plasma nitrite and corticosterone levels.

Regulating blood lipid activity

Palmatine achieved hypoglycemic effects by inducing induction of insulin release and insulin-mimicking activity. In addition, studies found that palmatine also inhibited the activity of lens aldose reductase, sucrase and maltase. In vivo research showed that palmatine reduced serum total cholesterol (TC) and triglycerides (TG) and increased serum high-density lipoprotein cholesterol.

Anticancer activity

Research showed that palmatine had broad anti-cancer activity. Palmatine had significant growth inhibitory effects on seven human cancer cell lines: 7701QGY, SMMC7721, HepG2, CEM, CEM/VCR, K III and Lewis. In addition, palmatine also had anti-cancer activity on MCF-7, U251, KB, CHOK-1, HT-29 and SiHacell lines. Palmatine induced apoptosis in human skin epithelial carcinoma cells (A431) in a concentration- and time-dependent manner via damaging severely to DNA and inhibiting the activity of Bcl-2 protein. In addition, palmatine can inhibit the proliferation and infiltration of cancer cells.

Antibacterial and antiviral activity

Palmitine has inhibitory effect on Gram-positive bacteria which is significantly stronger than that on Gram-negative bacteria, and 9-O-substituted palmatine derivatives exhibited stronger antibacterial activity.

Anti-inflammatory activity

Study showed, that palmatine can decrease the production of pro-inflammatory factors and increase the production of anti-inflammatory factors.

Other pharmacological activity

Studies showed that palmatine had antioxidant activity, had a protective effect on gastric ulcer, derivatives of palmatine were more effective against ulcerative colitis, including low cytotoxicity tointestinal epithelial cells. In addition, palmatine might have the antiarrhythmic effect, and provideprotection from myocardial ischemia-reperfusion injury.

Toxicity

A large number of studies have shown that palmatine has a complex effect on the metabolism of enzymes in the liver, and that palmatine has significant DNA toxicity. However, some 9-O-substituted palmatine derivatives exhibited less toxic than palmatine. In addition, palmatine had higher affinity to nucleic acids than serum proteins, which make them suitable candidates for delivery by serum proteins.{{Cite journal, last1=Khan, first1=Asma Yasmeen, last2=Suresh Kumar, first2=Gopinatha, date=2015-12-01, title=Natural isoquinoline alkaloids: binding aspects to functional proteins, serum albumins, hemoglobin, and lysozyme, url= , journal=Biophysical Reviews, language=en, volume=7, issue=4, pages=407–420, doi=10.1007/s12551-015-0183-5, issn=1867-2469, pmc=5418488, pmid=28510102

References

Isoquinoline alkaloids Quaternary ammonium compounds Phenol ethers Isoquinolinoisoquinolines