One new triterpenoids from Momordica charantia L

Momordica charantia L. (M. charantia) is an annual climbing herb in Cucurbitaceae. It is not only a food, but also a drug with a long history of application. This study aims to isolate and identify the chemical constituents form M. charantia and evaluate their inhibiting effect on Hcy-induced proliferation of VSMCs. Silica column chromatography, ODS silica column chromatography, Sephadex LH-20 column chromatography and semi-preparative HPLC were used to obtain one new compound (1). The inhibition on Hcy-induced proliferation of VSMCs 1 was tested through MTT method. As a result, 1 could partially rescue Hcy-induced proliferation of VSMCs at both 5 and 25 μM.

Transcriptomic Analysis of the Response of Susceptible and Resistant Bitter Melon (Momordica charantia L.) to Powdery Mildew Infection Revealing Complex Resistance via Multiple Signaling Pathways

The challenge of mitigating the decline in both yield and fruit quality due to the intrusion of powdery mildew (PM) fungus looms as a pivotal concern in the domain of bitter melon cultivation. Yet, the intricate mechanisms that underlie resistance against this pathogen remain inscrutable for the vast majority of bitter melon variants. In this inquiry, we delve deeply into the intricate spectrum of physiological variations and transcriptomic fluctuations intrinsic to the PM-resistant strain identified as '04-17-4' (R), drawing a sharp contrast with the PM-susceptible counterpart, designated as '25-15' (S), throughout the encounter with the pathogenic agent Podosphaera xanthii. In the face of the challenge presented by P. xanthii, the robust cultivar displays an extraordinary capacity to prolong the initiation of the pathogen's primary growth stage. The comprehensive exploration culminates in the discernment of 6635 and 6954 differentially expressed genes (DEGs) in R and S strains, respectively. Clarification through the lens of enrichment analyses reveals a prevalence of enriched DEGs in pathways interconnected with phenylpropanoid biosynthesis, the interaction of plants with pathogens, and the signaling of plant hormones. Significantly, in the scope of the R variant, DEGs implicated in the pathways of plant-pathogen interaction phenylpropanoid biosynthesis, encompassing components such as calcium-binding proteins, calmodulin, and phenylalanine ammonia-lyase, conspicuously exhibit an escalated tendency upon the encounter with P. xanthii infection. Simultaneously, the genes governing the synthesis and transduction of SA undergo a marked surge in activation, while their counterparts in the JA signaling pathway experience inhibition following infection. These observations underscore the pivotal role played by SA/JA signaling cascades in choreographing the mechanism of resistance against P. xanthii in the R variant. Moreover, the recognition of 40 P. xanthii-inducible genes, encompassing elements such as pathogenesis-related proteins, calmodulin, WRKY transcription factors, and Downy mildew resistant 6, assumes pronounced significance as they emerge as pivotal contenders in the domain of disease control. The zenith of this study harmonizes multiple analytical paradigms, thus capturing latent molecular participants and yielding seminal resources crucial for the advancement of PM-resistant bitter melon cultivars.

Kaguacidine A: a novel spirohydantoin-containing cucurbitane glycoside from vines of Momordica charantia L

The spirohydantoin-containing cucurbitane-type triterpenoid, kaguacidine A (1), was isolated and purified from 95% ethanol extract of vines of Momordica charantia L. (Cucurbitaceae). Its unprecedented chemical structure, a spirohydantoin substituent at C-23 of cucurbitane, was elucidated by extensive spectroscopic analyses, including HRESIMS, IR, optical rotation, 1 D- and 2 D-NMR spectra. The possible biosynthetic pathway is deduced and may be attributed to the metabolic activity of microbial symbionts in M. charantia L. Compound 1 was evaluated for anti-inflammatory activity against LPS-induced NO production in RAW 264.7 cells and anti-proliferative activity against four cancer cell lines, including HEp-2, MCF-7, Hep-G2, and WiDr. Compound 1 showed moderate anti-inflammatory activity with an IC50 value of 18.5 ± 0.4 μg/mL and weak anti-proliferative activity against MCF-7, HEp-2, Hep-G2, and WiDr with IC50 values of >40, 33.8 ± 0.6, 31.0 ± 0.7, and 27.0 ± 0.7 μM, respectively.

Momordica charantia fruit extract with antioxidant capacity improves the expression of tyrosine-phosphorylated proteins in epididymal fluid of chronic stress rats

OBJECTIVE

Although the protective effects of Momordica charantia L. (MC) extract on chemical-induced testicular damage have been studied, the preventive effects of MC extract on functional proteins in the epididymis under chronic stress have never been reported. This study investigated the protective effects of MC fruit extract on protein secretion, especially tyrosine-phosphorylated proteins, in the epididymis of rats exposed to chronic unpredictable stress (CUS).

METHODS

Total phenolic compounds (TPC), total flavonoid compounds (TFC) and antioxidant capacities of MC extract were measured. Adult male rats were divided into 4 groups: control group, CUS group, and 2 groups of CUS that received different doses of MC extract (40 or 80 mg/kg). In treated groups, rats were given MC daily, followed by induction of CUS (1 stressor was randomly applied from a battery of 9 potential stressors) for 60 consecutive days. Plasma corticosterone and testosterone levels were analyzed after the end of experiment. Expressions of heat-shock protein 70 (HSP-70) and tyrosine-phosphorylated proteins present in the fluid of the head and tail of the epididymis were quantified using Western blot.

RESULTS

MC extract contained TPC of (19.005 ± 0.270) mg gallic acid equivalents and TFC of (0.306 ± 0.012) mg catechin equivalents per gram, and had 2,2-diphenyl-1-picrylhydrazyl antioxidant capacity of (4.985 ± 0.086) mg trolox equivalents per gram, radical 50% inhibitory concentration of (2.011 ± 0.008) mg/mL and ferric reducing antioxidant power of (23.697 ± 0.819) µmol Fe(II) per gram. Testosterone level in the epididymis was significantly increased, while the corticosterone level was significantly improved in groups treated with MC extract, compared to the CUS animals. Particularly, an 80 mg/kg dose of MC extract prevented the impairments of HSP-70 and tyrosine-phosphorylated protein expressions in the luminal fluid of the epididymis of CUS rats.

CONCLUSION

MC fruit extract had antioxidant activities and improved the functional proteins secreted from the head and tail of the epididymis. It is possible to develop the MC fruit extract as a male fertility supplement for enhancing functional sperm maturation in stressed men.

Molecular docking and spectral shift supported toxicity profile of metaldehyde mollucide and the toxicity-reducing effects of bitter melon extract

Excessive use of metaldehyde to combat mollusks directly or indirectly endangers non-targeted organisms. The present study aimed to reveal the antitoxic potential of bitter melon (Momordica charantia L.) extract (BME) against metaldehyde-related toxicity in Allium cepa L. The experimental groups formed using A. cepa bulbs were exposed to aqueous solutions containing 350 mg/L BME, 700 mg/L BME, 200 mg/L metaldehyde, 200 mg/L metaldehyde +350 mg/L BME and 200 mg/L metaldehyde +700 mg/L BME, respectively. The bulbs in the control group dipped in tap water. Metaldehyde suppressed growth with respect to germination ratio, root elongation and weight gain parameters. In metaldehyde-administered group, mitotic index (MI) was reduced, while the frequencies of micronucleus (MN) and chromosomal aberrations (CAs) increased. Metaldehyde promoted CAs such as sticky chromosomes, vagrant chromosome, fragment, unequal distribution of chromatin, reverse polarization, bridge and multipolar anaphase in root tip meristem cells. Spectral shift and molecular docking confirmed the genotoxic effect of metaldehyde resulting from DNA-metaldehyde interaction. The DNA damage in root meristems was revealed using the Comet Assay. Metaldehyde stress provoked oxidative stress. Activities superoxide dismutase (SOD) and catalase (CAT) enzymes along with level of malondialdehyde (MDA) accumulation accelerated. In roots treated with metaldehyde, epidermis cell damage, flattened cell nucleus, cortex cell damage and cortex cell wall thickening were observed as meristematic cell damage. BME attenuated metaldehyde-induced toxicity in a dose-dependent manner. This study demonstrated the mitigative potential of plant derived BME with no-to-low side effects against hazardous chemicals including metaldehyde. Nature is the most valuable weapon against toxicity from pollutants. Therefore, the protective potential of BME against other harmful agents should be screened.

Exogenous melatonin increases salt tolerance in bitter melon by regulating ionic balance, antioxidant system and secondary metabolism-related genes

BACKGROUND

Melatonin is a multi-functional molecule widely employed in order to mitigate abiotic stress factors, in general and salt stress in particular. Even though previous reports revealed that melatonin could exhibit roles in promoting seed germination and protecting plants during various developmental stages of several plant species under salt stress, no reports are available with respect to the regulatory acts of melatonin on the physiological and biochemical status as well as the expression levels of defense- and secondary metabolism-related related transcripts in bitter melon subjected to the salt stress.

RESULTS

Herewith the present study, we performed a comprehensive analysis of the physiological and ion balance, antioxidant system, as well as transcript analysis of defense-related genes (WRKY1, SOS1, PM H⁺-ATPase, SKOR, Mc5PTase7, and SOAR1) and secondary metabolism-related gene expression (MAP30, α-MMC, polypeptide-P, and PAL) in salt-stressed bitter melon (Momordica charantia L.) plants in response to melatonin treatment. In this regard, different levels of melatonin (0, 75 and 150 µM) were applied to mitigate salinity stress (0, 50 and 100 mM NaCl) in bitter melon. Accordingly, present findings revealed that 100 mM salinity stress decreased growth and photosynthesis parameters (SPAD, ^Fv/_Fo, Y(II)), RWC, and some nutrient elements (K⁺, Ca²⁺, and P), while it increased Y(NO), Y(NPQ), proline, Na⁺, Cl^-, H₂O₂, MDA, antioxidant enzyme activity, and lead to the induction of the examined genes. However, prsiming with 150 µM melatonin increased SPAD, ^Fv/_Fo, Y(II)), RWC, and K⁺, Ca²⁺, and P concentration while decreased Y(NO), Y(NPQ), Na⁺, Cl^-, H₂O₂, and MDA under salt stress. In addition, the antioxidant system and gene expression levels were increased by melatonin (150 µM).

CONCLUSIONS

Overall, it can be postulated that the application of melatonin (150 µM) has effective roles in alleviating the adverse impacts of salinity through critical modifications in plant metabolism.

Anti-Aging Effect of Momordica charantia L. on d-Galactose-Induced Subacute Aging in Mice by Activating PI3K/AKT Signaling Pathway

Anti-aging is a challenging and necessary research topic. Momordica charantia L. is a common edible medicinal plant that has various pharmacological activities and is often employed in daily health care. However, its anti-aging effect on mice and the underlying mechanism thereof remain unclear. Our current study mainly focused on the effect of Momordica charantia L. on d-galactose-induced subacute aging in mice and explored the underlying mechanism. UHPLC-Q-Exactive Orbitrap MS was applied to qualitatively analyze the chemical components of Momordica charantia L. ethanol extract (MCE). A subacute aging mice model induced by d-galactose (d-gal) was established to investigate the anti-aging effect and potential mechanism of MCE. The learning and memory ability of aging mice was evaluated using behavioral tests. The biochemical parameters, including antioxidant enzyme activity and the accumulation of lipid peroxides in serum, were measured to explore the effect of MCE on the redox imbalance caused by aging. Pathological changes in the hippocampus were observed using hematoxylin and eosin (H&E) staining, and the levels of aging-related proteins in the PI3K/AKT signaling pathway were assessed using Western blotting. The experimental results demonstrated that a total of 14 triterpenoids were simultaneously identified in MCE. The behavioral assessments results showed that MCE can improve the learning and memory ability of subacute mice. The biochemical parameters determination results showed that MCE can improve the activity of antioxidant enzymes and decrease the accumulation of lipid peroxides in aging mice significantly. Furthermore, aging and injury in the hippocampus were ameliorated. Mechanistically, the results showed a significant upregulation in the protein expression of P-PI3K/PI3K and P-AKT/AKT (p < 0.01), as well as a significant reduction in cleaved caspase-3/caspase-3, Bax and P-mTOR/mTOR (p < 0.01). Our results confirm that MCE could restore the antioxidant status and improve cognitive impairment in aging mice, inhibit d-gal-induced apoptosis by regulating the PI3K/AKT signaling pathway, and rescue the impaired autophagy caused by mTOR overexpression, thereby exerting an anti-aging effect.

Purified Saponins in Momordica charantia Treated with High Hydrostatic Pressure and Ionic Liquid-Based Aqueous Biphasic Systems

Momordica charantia L. (Cucurbitaceae) is rich in saponins, which have multiple biological effects. In this study, the total saponins of M. charantia were extracted by high hydrostatic pressure (HHP) technology. The optimal extraction process was determined (ethanol concentration 68%, pressure-holding time 8 min, ratio of material to solvent 1:35 and pressure 510 MPa), and the extraction amount of saponins reached 127.890 mg/g. On this basis, an ionic liquid-based aqueous biphasic system was constructed to purify the total saponins. Under the optimized conditions, the purity of M. charantia saponins was 76.06%. Liquid chromatography–mass spectrometry (LC/MS) was used to characterize the saponins in the purified extract of M. charantia. It was found that there were four kinds of saponins in the extract of M. charantia: kuguaglycoside A, momordicoside L, kuguacin B and kuguacin J, providing a basis for the study of the biological activity of saponins.

In Vivo Treatment Efficacy of Essential Oil Isolated from Seeds of Momordica charantia in Streptozotocin-Induced Diabetes Mellitus

BACKGROUND

All parts of Momordica charantia L. have potential hypoglycemic properties in reversing the metabolic disorder of diabetes mellitus. However, there exists a need for preparing an effective and safer formulation of active phytochemicals. We have also reviewed and analyzed certain patents on such preparatory methods for Momordica charantia L. formulations.

OBJECTIVE

This study aimed to isolate essential oil from the seeds of Momordica charantia L., analyze its phytochemicals, and study their anti-diabetic effects.

METHODS

The essential oil was isolated by the hydrodistillation method and analyzed for phytochemicals by GC-MS. Furthermore, its acute toxicity was tested in rats. Anti-diabetic effects were evaluated in Streptozotocin-induced diabetic rats with 17.5 and 55 mg/kg b.wt of essential oil by evaluating blood glucose, serum lipid profile, liver glycogen, protein, and other serum markers such as ALT, AST, ALP, urea, and creatinine. The histologic changes in the liver, pancreas, and kidney were evaluated using Haematoxylin and Eosin staining.

RESULTS

The phytochemicals having hypoglycaemic and insulin induction potency were identified in the GC-MS analysis. A highly significant (p≤0.01; p≤0.001) reduction in blood glucose was observed from 17.5 mg/kg and 55 mg/kg essential oil treatments, respectively. Diabetes-associated metabolic alterations (p≤0.001) observed in diabetic control rats such as lipid profile, enzymes, glycogen, protein, urea, and creatinine were normalized upon treatment with essential oil. Moreover, the histologic changes in vital organs reversed in treated rats.

CONCLUSION

The essential oil of Momordica charantia L. seed has promising potency to normalize the metabolic changes of type II diabetes mellitus.

Effects of Storage Time and Temperature on Antioxidants in Juice from Momordica charantia L. and Momordica charantia L. var. abbreviata Ser

This study determined the antioxidant activities of juice from Momordica charantia L. (MC) and MC var. abbreviata Ser. (MCVAS) by analyzing 1,1-diphenyl-2-picrylhydrazyl (DPPH) scavenging ability, ferric reducing power (FRP), and total phenolic content (TPC). The effects of storage time and storage temperature on these antioxidant activities were investigated. Liquid chromatography-mass spectrometry was conducted to identify the major components of MC and MCVAS. The results revealed that the antioxidant activity of MCVAS was better than that of MC, possibly because of richer components of MCVAS. For MC and MCVAS, the scavenging concentrations of 50% DPPH were 3.33 and 1.19 mg/mL, respectively; moreover, the FRP values were 68.93 and 118.14 mg ascorbic acid equivalent/g dry weight, respectively; and the TPC values were 8.15 and 11.47 mg gallic acid equivalent/g dry weight, respectively. The antioxidant activities of MC and MCVAS decreased with storage time. High storage temperature decreased antioxidant activity more quickly than a low temperature. In addition, MC had exhibited a faster decline in DPPH scavenging ability and FRP than MCVAS during 24-day storage, but no difference was observed in TPC.

Four new cucurbitane-type triterpenes from Momordica charantia L. with their cytotoxic activities and protective effects on H2O2-damaged pancreatic cells

Four new cucurbitane-type triterpenes were isolated from the fruit of Momordica charantia L. The structures of the new compounds were identified based on HR-ESI-MS and 1D- and 2D-NMR spectroscopic methods. The cytotoxicity of the isolated compounds was evaluated using three human cancer cell lines, HeLa, Caco2, and U87. Compound 3 exhibited significant cytotoxic activity against HeLa cells with an IC₅₀ value of 11.18 μM. Additionally, the cytoprotective activity of these compounds was determined in vitro against H₂O₂-induced pancreatic injury. The results revealed that all the compounds obtained possess cytoprotective effects against H₂O₂-induced injury in MIN6 β-cells at a concentration of 10 μM.

Cucurbitane triterpenoids from the fruit of Momordica charantia L. and their anti-hepatic fibrosis and anti-hepatoma activities

Momordica charantia L. (Cucurbitaceae) is a popular vegetable and traditional folk medicine, that has been used for hundreds of years. In this study, three undescribed cucurbitane-type triterpene glycosides furpyronecucurbitane A, goyaglycoside I and charantagenin F along with nine known compounds were isolated from the immature fruit of Momordica charantia L. Their structures were identified on the basis of extensive 1D, 2D NMR and HRESIMS spectroscopy analysis. All isolated compounds were examined for their anti-hepatic fibrosis activity against murine hepatic stellate cells (t-HSC/Cl-6) and anti-hepatoma activity against two kinds of liver cancer cell lines (HepG2 and Hep3B). Among them, karaviloside III exhibited excellent inhibitory activity against activated t-HSC/Cl-6 cells and cytotoxic activity against Hep3B and HepG2 cell lines with IC₅₀ values of 3.74 ± 0.13, 16.68 ± 2.07 and 4.12 ± 0.36 μM, respectively, which may potential to be developed as a chemotherapy agent for treatment hepatic fibrosis or carcinoma and protection against both diseases.

Effect of Intrauterine Infusion of Momordica Charantia L. on Oxidative Stress and Pregnancy Rate in Infertile Cows

Introduction

The effect of intrauterine administration of Momordica charantia L. (MC) extract on oxidative changes and pregnancy rate in infertile cows was investigated.

Material and Methods

Endometrial smear specimens were taken from 40 cows with fertility problems for cytological examination, and the cows were randomly divided into two groups: group I (n = 20) was subjected to intrauterine administration of 40 mL (0.25 g/mL) of MC extract, group II (n = 20) was subjected to intrauterine administration of 40 mL of pure olive oil. Blood samples were taken starting from the day of administration of MC extract or olive oil (day 0) and then for three weeks at weekly intervals (days 7, 14, 21). Blood serum samples were evaluated for total antioxidant capacity (TAS), total oxidant level (TOS), oxidative stress index (OSI), lipid hydroperoxide (LOOH), and nitric oxide (NO) levels. In addition, on the 14^th day following treatment, two doses of PGF2α were administrated to all cows at 14-day intervals. Following the second PGF2α administration, insemination and GnRH administration was performed at the 60^th h after PGF2α treatment. Smear samples were stained with Giemsa and immunohistochemically to determine cytological changes and inflammatory status.

Results

According to cytological findings, subclinical endometritis was a prevalent disorder in cows with infertility problem (82.5%; 33/40). Additionally, 60.6% (20/33) of the cows with subclinical endometritis had acute inflammation, whereas remaining 13 cows had chronic endometritis. Of the cows with subclinical endometritis, 50% (8/16) and 35% (6/17) became pregnant in group I and II, respectively (P > 0.05). Although the oxidative stress parameters showed similarities between both groups (P > 0.05), there was a significant difference (P < 0.001) between the groups in terms of mean NO and LOOH levels (NO - 31.20 ± 11.38 vs 44.53 ± 11.50 μmol/L and LOOH - 1.22 ± 0.37 vs 1.89 ± 0.36 μmol/L).

Conclusion

The obtained results indicated that MC administration, especially in the presence of active inflammation, may improve the pregnancy rate by positive reduction of oxidative changes.

Separation of cucurbitane triterpenoids from bitter melon drinks and determination of partition coefficients using vortex-assisted dispersive liquid-phase microextraction followed by UHPLC analysis

A rapid, effective method applying vortex-assisted liquid-liquid microextraction before ultra-high performance liquid chromatography with mass spectrometry and evaporative light scattering detection was developed for the analysis of four cucurbitane triterpenoids (momordicoside L, momordicoside K, momordicoside F₂ , and 3β,7β,25-trihydroxy cucurbita-5,23(E)-dien-19-al) in bitter melon juices. Variables affecting the extraction efficiency including different extraction solvents, volume of extraction solvent, salt amount, acid condition, vortex speed and time were optimized thoroughly. Under the optimum conditions, precision was determined by the intra- and inter-day tests in a range of 1.1-5.7% and 2.9-4.0% (RSD), respectively, with recoveries between 95.7 and 106.1%. The calibration curves showed good linearity with square correlation coefficient of 0.9936-0.9991 (evaporative light scattering detection) and 0.9858-0.9989 (MS). The detection limits ranged from 0.8-1.9 ng/mL (MS) to 3-10 ng/mL (evaporative light scattering detection) for these compounds. Enrichment factors of four target compounds were between 27 and 63 times. The proposed method was also used to determine the apparent solvent/water partition coefficients of analytes within the range of 53-120. The developed method can effectively enrich and quantify cucurbitane triterpenoids from bitter melon drinks.

Anti-helminthic activity of Momordica charantia L. against Fasciola hepatica eggs after twelve days of incubation in vitro

Fasciolosis, a parasitic disease caused by the trematode Fasciola hepatica underreported is expanding both in human and animal population, throughout the world. The constant use of synthetic drugs to treat this condition has led to the natural selection of resistant strains of the parasite. Hence, there is a growing focus on the potential anti-helminthic properties of medicinal plants and phytopharmaceuticals. The current study assessed the potential anti-fasciolicide action of Momordica charantia leaf extracts and fractions on the eggs of F. hepatica parasites. The lyophilized crude extract (CE) of M. charantia leaves and its sub-fractions, obtained from liquid-liquid partitioning with organic solvents, were analysed by High Performance Liquid Chromatography (HPLC), suspended in 1% DMSO and used in in vitro tests. Quadruplicates of 50F. hepatica eggs were incubated at 23°C with M. charantia leaf CE in different concentrations. After 12days no larvae were formed in eggs incubated with CE concentrations above 12.5mg/mL. Eggs incubated with CE sub-fractions at concentrations of 1000, 100, 10, 1, 0.1, 0.01μg/mL affected embryonic development, with n-butanol presenting the strongest inhibition of miracidia formation. In contrast, on the 12th day, 90% of the miracidia hatched in the control experiments using 0.03% DMSO whereas embryogenesis was completely abolished with any concentration of albendazole sulphoxide ABZ(SO). Chemical analysis of the CE and sub-fractions revealed a prominent presence of flavonoids. HPLC-MS confirmed Quercetin to be one of the main flavonoids present in the CE and the n-butanol subfraction. This is the first study to analyse the potential anti-fasciolicide action of M. charantia leaf CE and subfractions.

The cytotoxicology of momordicins I and II on Spodoptera litura cultured cell line SL-1

Momordicin I and II are secondary metabolites from bitter melon (Momordica charantia L.) that are toxic to the Spodoptera litura ovary cell line (SL-1 cell). Both momordicin I and II significantly inhibited SL-1 cells proliferation. IC50 values after 24 h were 8.35 and 82.31 µg/mL, 6.11 and 77.49 µg/mL for 36 h, 4.93 and 49.42 µg/mL for 48 h for cells treated by momordicin I and II, respectively. IC50 values of the azadirachtin A control were 149.63, 54.54 and 23.66 µg/mL at 24, 36 and 48 h respectively, indicating that the cytotoxicity of momordicin I was significantly higher than that of momordicin II and azadirachtin A. Using inverted phase contrast microscopy we found that after 24 h exposure to momordicin I and II, cell shapes changed to circular, swelling increased, adherence ability declined and the cellular membrane bubbled. After 48 h exposure to momordicin I, most cells were suspended and dead; vacuole deformation and cytoplasm leakage indicated that momordicin I was more toxic to the cytoskeleton than momordicin II. Cells treated with momordicin I and II inhibited glucose absorption by 23.04 and 13.38% after 48 h and 47.60 and 20.92% after 60 h. Flow cytometry analysis suggested that SL-1 cells treated with momordicin I and II dramatically accumulated during the G2/M phase of the cell cycle, and total cell protein content increased by 56.93 and 35.81% respectively after 48 h treatment. Following treatment with momordicin I and II the karyotheca dissolved, the chromatin condensed abnormally and the nucleoli were damaged, migrated, or disappeared. The PI fluorescent value by FCM showed that the relative fluorescent intensity of SL-1 cells induced by momordicin I and II increased to 521.45 and 370.17, higher than 135.04 induced by control group treatment for 48 h. This indicated significant damage to the cytomembrane. Overall, the results demonstrate that suppression of cytoskeletal function, interference of mitotic figures and destruction of nuclear structure are effects of momordicin I and II exposure. These effects play major roles in momordicin I and II inhibition of SL-1 cells growth. The mode of action by which momordicins inhibit insect cell growth and development may be useful in the development of novel pest control formulations containing cucurbitane-type triterpene glycosides.

Antinociceptive and antiallodynic effects of Momordica charantia L. in tibial and sural nerve transection-induced neuropathic pain in rats

OBJECTIVE

This study was designed to investigate the ameliorative potential of Momordica charantia L. (MC) in tibial and sural nerve transection (TST)-induced neuropathic pain in rats.

MATERIALS AND METHODS

TST was performed by sectioning tibial and sural nerve portions (2 mm) of the sciatic nerve, and leaving the common peroneal nerve intact. Acetone drop, pin-prick, hot plate, paint-brush, and walking track tests were performed to assess cold allodynia, mechanical and heat hyperalgesia, and dynamic mechanical allodynia and tibial functional index, respectively. The levels of tumour necrosis factor (TNF)-alpha and thio-barbituric acid reactive substances (TBARS) were measured in the sciatic nerve as an index of inflammation and oxidative stress. MC (all doses, orally, once daily) was administered to the rats for 24 consecutive days.

RESULTS

TST led to significant development of cold allodynia, mechanical and heat hyperalgesia, dynamic mechanical allodynia, and functional deficit in walking along with rise in the levels of TBARS and TNF-alpha. Administration of MC (200, 400, and 800 mg/kg) significantly attenuated TST-induced behavioural and biochemical changes. Furthermore, pretreatment of BADGE (120 mg/kg, intraperitoneally) abolished the protective effect of MC in TST-induced neuropathic pain.

CONCLUSIONS

Collectively, it is speculated that PPAR-gamma agonistic activity, anti-inflammatory, and antioxidative potential is critical for antinociceptive effect of MC in neuropathic pain.