The effect of Piper laetispicum extract (EAE-P) during chronic unpredictable mild stress based on interrelationship of inflammatory cytokines, apoptosis cytokines and neurotrophin in the hippocampus.[Pubmed: 26183217]

The Piper laetispicum C.DC. (Piperaceae) is a traditionally used herb in China for invigorating circulation and reducing stasis, detumescence and analgesia, which is distributed in the southern part of China and the southeastern part of Asia. Previous studies demonstrated that the ethyl acetate extract (EAE-P) of P. laetispicum possesses a significant antidepressant-like effect at doses higher than 60 mg/kg in Kunming (KM) mice, and this effect was not due to an increase in locomotive activity.

Structure-activity relationship of 39 analogs of laetispicine with antidepressant properties.[Pubmed: 24228607]

The natural product Laetispicine ( N -isobutyl-(3,4-methylendioxyphenyl)-2E, 4E, 9E-undecatrienoamide), was isolated from the Piper laetispicum C. DC and screened, for its antidepressant activity and antinociceptive effects. Structure-functional activities of five natural products indicated that biological activity is dependent on double bonds present within the benzene ring and a conjugated double bond located at positions 2-3 and 4-5 in the molecular structure. To further understand the structural-activity relationship of Laetispicine as a new potent and safe antidepressant, the structural-activity relationship of 39 analogs of Laetispicine were synthetized and tested in forced swimming tests in mice whilst also in protective effects against glutamate or H 2 O 2 induced apoptosis in PC12 cells. The results show that the compound 30 - N -isobutyl-11-(4-chlorophenyl) undeca-2E,4E,9E-trienamide exhibited the same activity as the parental compound Laetispicine, and furthermore, the effective dose of this compound is lower than Laetispicine. Therefore, the compound 30 might be a potentially useful therapy in the treatment of depression. For structure, the conjugated double bonds located at 2-3, 4-5 and isolated double bonds from benzene ring are necessary for the antidepressant activities no matter the different length of carbon chain; the isobutyl connected with acylamino also are necessary; and the benzodioxole moiety is replaceable, the halogen atom in phenyl ring at the para-position could enhance this kind of activity.

Total synthesis and antidepressant activities of laetispicine and its derivatives.[Pubmed: 22306832]

The first total synthesis of laetispicine (1a), an amide alkaloid isolated from the stems of Piper laetispicum C.DC (Piperaceae), and the synthesis of some of its derivatives were described. Based on the evaluation of antidepressant activities in the forced swimming test, compounds 1h and 1i were identified as potent and safe antidepressant lead compounds.

Studies on antidepressant and antinociceptive effects of ethyl acetate extract from Piper laetispicum and structure-activity relationship of its amide alkaloids.[Pubmed: 21787850]

Piper laetispicum C.DC. (Piperaceae), is an endemic climbing, glabrous plant distributed in the southern part of China. A novel alkaloid amide, Laetispicine, from it has been proven to possess antidepressant activity. In this present study, antidepressant and antinociceptive effects of the ethyl acetate extract (EAE) of P. laetispicum have been studied in forced swimming, open field, acetic acid writhing and formalin tests in KM mice. A significantly antidepressant-like effect was showing at doses of higher than 60 mg/kg, which was not due to an increase in locomotive activity. The EAE also presented an analgesic effect, in our studies. At lower doses (30 mg/kg) the antinociceptive effect was likely mediated via peripheral inflammation and changes in central processing, and at higher doses (120 mg/kg) that was due to both central and peripheral pathways. We also quantitatively analyzed the major components of EAE by HPLC and approached the structure-activity relationship between structure of amide alkaloids and its antidepressant activities. The antidepressant effective components of EAE might be Leatispiamide A and Laetispicine. In their molecular structures, the isolated double bond from benzene ring and conjugated double bond located at 2-3 and 4-5 were necessary for its antidepressant activity.

Pharmacokinetics of laetispicine and its brain distribution in rats.[Pubmed: 20821821]

Laetispicine, which is a novel amide alkaloid isolated from the stem of Piper laetispicum, has been proven to possess antidepressant and antinociceptive effects. This study examined the pharmacokinetic characteristics of laetispicine in plasma and brain distribution in rats by a simple sensitive HPLC-UV method. The separation was performed on a reverse-phase ODS column (250 mm x 4.6 mm, i.d., 5 microm) with a mobile phase composed of acetonitrile-water (75:25, v/v) as the mobile phase at a flow rate of 1.0 ml/min with UV detection at 259 nm. The calibration curve of laetispicine in rat plasma showed excellent linear behavior between 0.005-5.0 microg/ml (r2 = 0.9992), and between 0.02-0.5 microg/ml (r2 = 0.9952) in rat brain samples. The lower limit of quantification (LLOQ) was found to be 0.005 microg/ml in rat plasma and 0.02 microg/ml in rat brain samples. This HPLC assay was a precise and reliable method for the analysis of laetispicine in pharmacokinetic studies. Laetispicine was rapidly and extensively transported across the blood-brain barrier (BBB) and distributed into different brain regions.

Laetispicine, an amide alkaloid from Piper laetispicum, presents antidepressant and antinociceptive effects in mice.[Pubmed: 19447013]

In the present work, we studied the effect of laetispicine, an amide alkaloid isolated from the stems of Piper laetispicum (Piperaceae), in forced swimming, open field, acetic acid writhing and formalin tests in KM mice to assess antidepressant and antinociceptive effects. A significant and dose-dependent decrease in the immobility time, as evaluated by the forced swimming test, was observed after laetispicine administration (38.18, 39.79, 58.77 and 67.28% decreased at the doses of 5, 10, 20, 40mg/kg, respectively), suggesting an antidepressant effect. Furthermore, in the open field test, laetispicine at the given doses did not alter the number of crossings and rearing, as compared to controls. Results from writhing and formalin tests showed that laetispicine reduced the number of writhing in mice in a dose-dependent manner, attenuated the licking and spiting time of the injected paw in the first phase of formalin test. The antinociceptive effect of laetispicine was not affected by pre-treatment (i.p.) with naloxone (2mg/kg). In conclusion, we showed that laetispicine possessed significant antidepressant and antinociceptive properties, making this drug potentially useful in depression and pain.

[Antidepressant amides from Piper laetispicum C. DC].[Pubmed: 16011266]

To investigate the antidepressant constituents of Piper laetispicum C. DC.