Essential oil of Pterocarpus santalinus L. alleviates behavioral impairments in social defeat stress-exposed mice by regulating neurotransmission and neuroinflammation

BACKGROUND

Pterocarpus santalinus L. essential oil (PSEO) is traditionally employed for treating fever and mental aberrations. We aim to explore the antidepressant potential of intranasal PSEO in social defeat stress (SDS)-expose mice and identify its mechanisms and components.

METHODS

PSEO components were analyzed using gas chromatography-mass spectrometry (GC-MS). C57BL/6 mice underwent a 10-day SDS with intranasal PSEO (10, 20 mg/kg) for 21 days. Efficacy was evaluated through changes in behaviors and serum corticosterone (CORT), hippocampal neurotransmitter, and inflammatory cytokine levels. In vitro effects were examined using primary hippocampal neurons, PC12 and BV2 cells.

RESULTS

GC-MS identified 22 volatile compounds in PSEO, and (+)-ledene (16.7%), cedrol (13.5%), and isoaromadendrene epoxide (7.0%) as major components. PSEO (20 mg/kg) significantly reversed SDS-induced social withdrawal, increased open-area explorations in the open field test (OFT) and elevated plus maze (EPM) test, and reduced immobility time in the tail suspension test (TST) and forced swimming test (FST). PSEO downregulated serum CORT and hippocampal interleukin (IL)-1β, IL-6, and tumor necrosis factor (TNF)-α levels, while increasing hippocampal gamma-aminobutyric acid (GABA), norepinephrine (NE), and serotonin (5-HT) levels. PSEO (0.1, 1, 10 µg/mL) reduced neurotoxicity and neuroinflammation in PC12 and BV2 cells, respectively. PSEO (10 µg/mL) enhanced glutamic acid decarboxylase 6 (GAD6)- and GABA B receptor 1 (GABABR1)-positive puncta in the hippocampal neurons and FM1-43 fluorescence intensity.

CONCLUSION

Intranasal PSEO exhibited antidepressant-like effects on SDS-exposed mice, potentially through modulating stress hormone, neurotransmission, and neuroinflammation. Further investigation into the pharmacokinetics, bioavailability, and mechanisms of (+)-ledene, cedrol, and isoaromadendrene epoxide is needed.

Evaluation of antitrypanosomal activity of Pterocarpus santalinoides L'H'erit ex DC hydroethanol leaf extract in rats experimentally infected with Trypanosoma brucei

ETHNOPHARMACOLOGICAL RELEVANCE

The leaves of Pterocarpus santalinoides are used alone or with other plants by traditional healers in some Southern Nigerian and Ivorian rural villages to treat blood parasitic infections including trypanosomiasis and malaria. However, their efficacy and safety remains doubtful.

AIM

To evaluate the antitrypanosomal activity of Pterocarpus santalinoides hydroethanol leaf extract (PSELE) in vitro and in vivo.

MATERIALS AND METHODS

The phytochemical and acute toxicity studies of PSELE were performed using standard methods. Eleven different concentrations of the extract were screened for in vitro antitrypanosomal activity. For the in vivo study, twenty-five female albino rats were randomly assigned into five groups of five rats each. Group A was the uninfected and untreated group while groups B - E were infected intraperitoneally with 10⁶ trypanosomes. Group C rats were treated once on day 11 post infection (PI) with 7 mg/kg diminazene aceturate while groups D and E rats were also treated on same day with 200 mg/kg and 400 mg/kg PSELE respectively for seven days. The level of parasitaemia (LOP), survivability, packed cell volume (PCV), total leucocyte count (TLC), total erythrocyte count (TEC), body weight and rectal temperature were used to assess the antitrypanosomal effect of PSELE.

RESULTS

Phytochemical analysis revealed the presence of flavonoids, tannins, carbohydrates and reducing sugar. No sign of toxicity or mortality was observed following acute toxicity study at a single dose of 2000 mg/kg. The LC₅₀ of PSELE was 0.0625 mg/ml. Parasitaemia was first detected on day 8 and all infected rats became parasitaemic on day 10 (PI). PSELE significantly reduced (p < 0.05) LOP, improved PCV, TEC and prolonged survival time of the rats compared with the infected untreated group B.

CONCLUSION

It was therefore concluded that PSELE is safe, possesses some antitrypanosomal activity and may serve as a lead for the development of an effective alternative antitrypanosomal drug.

Pterostilbene, an active component of the dragon's blood extract, acts as an antidepressant in adult rats

BACKGROUND

Hippocampal neurogenesis has been widely considered as one of the potential biological mechanisms for the treatment of depression caused by chronic stress. Many natural products have been reported to be beneficial for neurogenesis.

OBJECTIVES

The present study is designed to investigate the effect of dragon's blood extract (DBE) and its biologically active compound, pterostilbene (PTE), on hippocampal neurogenesis.

METHODS

The male Sprague-Dawley (SD) rats were used in this study, which were maintained on the normal, DBE and PTE diet groups for 4 weeks before dissection in the normal rat model and behavioral testing in the CUS depression rat model. Meanwhile, DMI-treated rats are subcutaneously injected with DMI (10 mg/kg, i.p.).

RESULTS

Results revealed that DBE and PTE have the ability to promote hippocampal neurogenesis. DBE and PTE also promoted the proliferation of neural stem cells isolated from the brain of suckling rats. Oral administration of DBE and PTE induced the proliferation, migration, and differentiation of neural progenitor cells (NPCs) in chronic unexpected stressed (CUS) model rats, and improved the behavioral ability and alleviated depress-like symptoms of CUS rats. It was also observed that PTE treatment significantly induced the expression of neurogenesis-related factors, including BDNF, pERK, and pCREB.

CONCLUSION

Oral administration of PTE could affect neurogenesis and it is likely to be achieved via BDNF/ERK/CREB-associated signaling pathways.

Extraction of biomedical compounds from the wood of Pterocarpus macarocarpus Kurz heartwood

Some wood can be used as traditional Chinese medicine. The medicinal value of wood is associated with its extractives. Pterocarpus macarocarpus Kurz heartwood is a kind of top valuable reddish hardwood in making furniture and handicrafts, but the research about medicine value of this wood is not enough. In order to investigate the high value biomedical compounds in Pterocarpus macarocarpus Kurz heartwood, the woody extractives were obtained by Soxhlet extraction and ultrasonic extraction with benzene-ethanol (1:2, v/v) solvent simultaneously and were analyzed by Gas Chromatography-Mass Spectrometer (GC-MS). Combining with the results of the two extraction methods, 44 compounds can be identified in total. Amony these identified compounds, there were 5 flavonoids, 15 terpenes and 3 steroidal compounds. The representative biomedical compositions were homopterocarpin, medicarpin, (-)-pterocarpin, formononetin, β-eudesmol, stigmasterol, linoleic acid and so on, which indicated that the extractives from Pterocarpus macarocarpus Kurz heartwood have huge potential in biomedicine. This research provides scientific basis for further comprehensive utilization of Pterocarpus macarocarpus Kurz heartwood as Chinese medicine.

Characterization of Pterocarpus erinaceus kino extract and its gamma-secretase inhibitory properties

ETHNOPHARMACOLOGICAL RELEVANCE

The aqueous decoction of Pterocarpus erinaceus has been traditionally used in Benin against memory troubles.

AIM OF THE STUDY

New strategies are needed against Alzheimer׳s disease (AD), for, to date, AD treatment is symptomatic and consists in drugs treating the cognitive decline. An interesting target is the β-amyloid peptide (Aβ), whose accumulation and progressive deposition into amyloid plaques are key events in AD aetiology. Identifying new and more selective γ-secretase inhibitors or modulators (none of the existing has proven so far to be selective or fully efficient) appears in this respect of particular interest. We studied the activity and mechanisms of action of Pterocarpus erinaceus kino aqueous extract, after the removal of catechic tannins (KAST).

METHODS AND RESULTS

We tested KAST at non-toxic concentrations on cells expressing the human Amyloid Precursor Protein (APP695), as well as on primary neurons. Pterocarpus erinaceus extract was found to inhibit Aβ release in both models. We further showed that KAST inhibited γ-secretase activity in cell-free and in vitro assays, strongly suggesting that KAST is a natural γ-secretase inhibitor. Importantly, this extract did not inhibit the cleavage of Notch, another γ-secretase substrate responsible for major detrimental side effects observed with γ-secretase inhibitors. Epicatechin was further identified in KAST by HPLC-MS.

CONCLUSION

Pterocarpus erinaceus kino extract appears therefore as a new γ-secretase inhibitor selective towards APP processing.

Hypoglycaemic activity of Pterocarpus marsupium Roxb

The antidiabetic activity of various subfractions of the alcohol extract of the bark of Pterocarpus marsupium Roxb. was evaluated in alloxan-induced diabetic rats. The effect of these extracts on lipid profile and liver function tests were also assessed to evaluate their activity in controlling diabetes related metabolic alterations. The parameters measured were plasma glucose, total protein, cholesterol, triglycerides, alkaline phosphatase, SGOT and SGPT. The results indicate the effective role of Pterocarpus marsupium on the above mentioned parameters indicating that Pterocarpus marsupium can also control the diabetes related metabolic alterations apart from controlling the glucose levels. Among the fractions tested the butanol subfraction was found to be more active in comparison with other subfractions. It can be concluded that the butanol subfraction of the alcohol extract of Pterocarpus marsupium exhibits significant antidiabetic activity and corrects the metabolic alterations in diabetic rats and this activity may resemble insulin-like properties.

Structural basis for the recognition of complex-type biantennary oligosaccharides by Pterocarpus angolensis lectin

The crystal structure of Pterocarpus angolensis lectin is determined in its ligand-free state, in complex with the fucosylated biantennary complex type decasaccharide NA2F, and in complex with a series of smaller oligosaccharide constituents of NA2F. These results together with thermodynamic binding data indicate that the complete oligosaccharide binding site of the lectin consists of five subsites allowing the specific recognition of the pentasaccharide GlcNAc beta(1-2)Man alpha(1-3)[GlcNAc beta(1-2)Man alpha(1-6)]Man. The mannose on the 1-6 arm occupies the monosaccharide binding site while the GlcNAc residue on this arm occupies a subsite that is almost identical to that of concanavalin A (con A). The core mannose and the GlcNAc beta(1-2)Man moiety on the 1-3 arm on the other hand occupy a series of subsites distinct from those of con A.

Selective COX-2 inhibition by a Pterocarpus marsupium extract characterized by pterostilbene, and its activity in healthy human volunteers

In this study, an extract of Pterocarpus marsupium Roxb. containing pterostilbene has been evaluated for its PGE2-inhibitory activity in LPS-stimulated PBMC. In addition, the COX-1/2 selective inhibitory activity of P. marsupium (PM) extract was investigated. Biological activity, as well as safety of PM extract was evaluated in healthy human volunteers. PM extract, pterostilbene and resveratrol inhibited PGE2 production from LPS-stimulated human peripheral blood mononuclear cells (PBMC) with IC50 values of 3.2 +/- 1.3 microg/mL, 1.0 +/- 0.6 microM and 3.2 +/- 1.4 microM, respectively. When pterostilbene content of PM extract is calculated, PGE2 production inhibition of PM extract is comparable to PGE2 production inhibition of purified pterostilbene. Furthermore, in a COX-1 whole blood assay (WBA) PM extract was not effective while in a COX-2 WBA, PM extract decreased PGE2 production indicating COX-2 specific inhibition. In healthy human volunteers, the oral use of 450 mg PM extract did not decrease PGE2 production ex vivo in a WBA. Pterostilbene levels in serum were increased, but were 5-fold lower than the observed IC50 for PGE2 inhibition in LPS-stimulated PBMC. No changes from base-line of the safety parameters were observed and no extract-related adverse events occurred during the study. In conclusion, this is the first study to describe the selective COX-2 inhibitory activity of a Pterocarpus marsupium extract. Moreover, the PGE2 inhibitory activity of PM extract was related to its pterostilbene content. In humans, 450 mg PM extract resulted in elevated pterostilbene levels in serum, which were below the active concentration observed in vitro. In addition, short-term supplementation of 450 mg PM extract is considered to be a safe dose based on the long history of use, the absence of abnormal blood cell counts and blood chemistry values and the absence of extract-related adverse events. This strongly argues for a dose-finding study of PM extract in humans to corroborate the in vitro observed inhibitory activity on PGE2 production in order to resolve the potential use of PM extract in inflammatory disorders and/or inflammatory pain.

Upregulation of Glut-4 and PPAR gamma by an isoflavone from Pterocarpus marsupium on L6 myotubes: a possible mechanism of action

The purpose of the present study is to analyse the influence of Pterocarpus marsupium methanolic extract and isolated Pterocarpus marsupium isoflavone on a battery of cellular targets Glut-4, PPAR gamma and PI3 kinase. Pterocarpus marsupium is an anti-diabetic plant indigenous to South India. Sequential extraction performed with different solvents were analysed for glucose uptake activity at each step. Fraction-9 showing maximum glucose activity on glucose uptake was purified by column chromatography and the structure was elucidated as 7-O-alpha-L-rhamnopyranosyl oxy-4'-methoxy-5-hydroxy isoflavone using NMR and mass spectroscopy. The significant glucose uptake showed by Pterocarpus marsupium crude and pure was comparable with insulin and rosiglitazone. Elevation of Glut-4 and PPARgamma gene expression in parallel with glucose uptake supported the in vitro glucose uptake activity of Pterocarpus marsupium methanolic extract and Pterocarpus marsupium isoflavone. The inhibitory effect of cycloheximide on Pterocarpus marsupium methanolic extract and Pterocarpus marsupium isoflavone-mediated glucose uptake suggested that new protein synthesis is required for elevated Glut-4 protein expression. PI3 kinase plays an important role in glucose transport and activated by Pterocarpus marsupium methanolic extract but not the isolated pure isoflavone. Therefore, we postulate that the isoflavone from Pterocarpus marsupium may activate glucose transport by a PI3 kinase independent pathway, which require further analysis.

Pterocarpus santalinus: a traditional herbal drug as a protectant against ibuprofen induced gastric ulcers

The ethanol extract of Pterocarpus santalinus (PS) was evaluated for gastroprotection in rats using ibuprofen as the induction model. Rats treated with PS (100-400 mg/kg) showed a significant reduction in gastric lesions. PS at a dose of 200 mg/kg was found to be the minimum effective dose and hence further studies with that dose were carried out. PS treatment increased the LDH activity and decreased the lipid peroxidation levels. The extract had the ability to increase the antioxidant enzymes SOD, CAT and GPx when compared with the untreated but induced rats. The membrane bound ATPases - H(+)K(+)ATPase, Na(+)K(+)ATPase and Ca(2+)ATPases were increased upon the induction with ulcerogen. The treated group showed a decrease in the activities of these enzymes and also had the ability to restore the sodium and potassium ion concentrations to near normal levels, which were altered by ibuprofen mediated acid stimulation. The results suggest that the antiulcer properties of PS could traced to its acid inhibiting potential, antioxidant activity and the ability to maintain functional integrity of the cell membranes.

Anti-cataract activity of Pterocarpus marsupium bark and Trigonella foenum-graecum seeds extract in alloxan diabetic rats

Long-term complications are frequently encountered in diabetes mellitus and are difficult to treat. This study was undertaken to assess the effect of three antidiabetic plants on the development of cataract in rats. An aqueous extract of Pterocarpus marsupium Linn bark (PM, Hindi name: Vijaysar) (1 g kg(-1) day(-1)), Ocimum sanctum Linn leaves (OS, Hindi name, Tulsi) (200 mg kg(-1) day(-1)) and alcoholic extract of Trigonella foenum-graecum Linn seeds (FG, Hindi name, Methi) (2 g kg(-1) day(-1)) were given to alloxan (120 mg kg(-1)) diabetic rats until the development of cataract. Serum glucose and body weight were monitored at regular intervals while cataract was examined through naked eye as well as slit lamp at 75, 100 and 115 days after alloxan administration. Administration of all the three plant extracts exerted a favorable effect on body weight and blood glucose, the effects were best with PM followed by FG and OS. On the course of cataract development, PM followed by FG exerted anti-cataract effect evident from decreased opacity index while OS failed to produce any anti-cataract effect in spite of significant antihyperglycemic activity.

Role of Selected Indian Plants in Management of Type 2 Diabetes: A Review

Type 2 diabetes has become a global epidemic. Modern medicines, despite offering a variety of effective treatment options, can have several adverse effects. Ayurveda, a science that uses herbal medicines extensively, originated in India. Of considerable interest is the adoption of Ayurveda by the mainstream medical system in some European countries (e.g., Hungary), emphasizing this modality is increasing worldwide recognition. From ancient times, some of these herbal preparations have been used in the treatment of diabetes. This paper reviews the accumulated literature for 10 Indian herbs that have antidiabetic activity and that have been scientifically tested. Few of these herbs, such as Momordica charantia, Pterocarpus marsupium, and Trigonella foenum greacum, have been reported to be beneficial for treating type 2 diabetes. Mechanisms such as the stimulating or regenerating effect on beta cells or extrapancreatic effects are proposed for the hypoglycemic action of these herbs.

Antibacterial activity of Pterocarpus indicus

The leaves, root and stem barks of Pterocarpus indicus were successively partitioned with petrol, dichloromethane, ethyl acetate, butanol and methanol. All the fractions exhibited a wide spectrum of antibacterial activity. The activity was more pronounced in the butanol and methanol fractions. None were active against the moulds.

Effects of some traditional plant extracts on rat oestrous cycle compared with Clomid

It is well known that the plant kingdom contains numerous bioactive substances affecting the regulation of reproduction. The present study was undertaken to examine the putative contraceptive effects of three traditional plant extracts from Côte d'Ivoire Pharmacopea. It concerns Afrormosia laxiflora (Papilionacea), Pterocarpus erinaceus (Papilionacea) and Cola nitida (Sterculiacea) stem bark. Data showed that treatment of rats with these plant extracts induced ovulation and oestrous cycle blockade at the dioestrous II stage. The analysis of the principal hormones involved in oestrous cycle regulation showed that the plant extracts decreased gonadotropin release (both LH and FSH). In fact, A. laxiflora, P. erinaceus and C. nitida extracts inhibited gonadotropin release as an antiestrogen-like substance.